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Docherty, Anna Kerns John Gerald. "Dopamine and emotion processing in schizotypal anhedonia." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6872.
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Title from PDF of title page (University of Missouri--Columbia, viewed on Apr. 12, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. John Kerns. Includes bibliographical references.
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Pitt, Joanna Diana (Jodi). "Mind wandering and anhedonia : a systematic review ; An experience sampling study : does mind wandering mediate the link between depression and anhedonia?" Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/23430.
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Background: There is increasing theoretical interest in the idea that a greater tendency for the mind to wander may reduce positive emotion experience, with specific interest in clinical conditions such as depression that are characterised by reduced pleasure experience (anhedonia). However, it is unclear to what degree these claims are empirically supported. Objective: A systematic review was conducted to examine the evidence regarding the association between mind wandering and positive emotion experience. Method: The Cochrane library, MEDLINE, PsycINFO, and Web of Knowledge databases were searched. A narrative discussion considered both the pattern of findings and the methodological approaches utilised in this literature. Results: 879 studies were identified and 21 relevant papers were fully reviewed, consisting of cross-sectional, prospective and manipulation studies. Conclusions: Fourteen out of 15 cross-sectional studies supported the claim that increased mind wandering was related to decreased pleasure experience. One prospective study indicated that mind wandering generally preceded but was not subsequent to reductions in positive mood. There were six studies that manipulated mind wandering experimentally, four of which found that inducing greater mind wandering led to reduced positive affect and two of which found null results. Overall, this literature supports the claim that greater mind wandering is related to reduced positive affect. However, very few studies examined this relationship in the context of depression and therefore it remains to be established if these findings generalise to clinical populations. Empiricial Paper: Previous research has established that greater levels of mind wandering are associated with reduced positive affect (PA) in the general population. The present study aims to examine whether this mechanism may mediate the relationship between depression and reduced PA (anhedonia). A community sample (N = 69) with differing levels of depression severity took part. Using experience sampling methodology, we measured mind wandering and PA during everyday life and when completing a few scheduled positive activities. To examine if mind wandering specifically influenced PA or emotion experience more generally, we additionally measured levels of negative affect (NA). Across both contexts, both greater mind wandering and greater depression severity were independently associated with reduced PA and increased NA. Greater depression severity was associated with increasing levels of mind wandering in everyday life, but not during scheduled positive activities. Mind wandering did not mediate the link between depression and reduced PA/increased NA. Exploratory analyses did however reveal that a greater tendency for the mind wander to negative rather than positive themes did mediate the link between depression and reduced PA in everyday life. We replicated previous findings that increased mind wandering is related to reduced PA and increased NA but there was no evidence that this mediated the relationship between depression and altered affective experience. However, the greater tendency for the mind to wander to negative themes may mediate the link between depression and affect. If depression treatment approaches are to target mind wandering this suggests they should therefore focus on mind wandering valence in addition to extent.
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Skillicorn, Deiniol H. D. S. "Cognitive processes and emotion cue processing in introvertive anhedonia." Thesis, Cardiff Metropolitan University, 2010. http://hdl.handle.net/10369/2717.
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Executive cognitive processes and emotion cue processing was explored in introvertive anhedonia, the O-LIFE’s negative schizotypal trait dimension, with the aim of identifying endophenotypes. The experimental work of the thesis was conducted in three distinct parts. The first two used reaction time tasks of selective attention to examine 1) the possibility of a general abnormality in executive cognitive functioning, and 2) the possibility of an emotion cue processing abnormality. Results from these two parts informed the development of the final experiment that used procedures adapted from animal associative learning to examine the interaction between executive cognitive processes and the processing of positive and negative emotional cues in 1) the learning of differentially reinforced biconditional discrimination and 2) the sensitivity to changes in the emotional valence of outcomes. Two experiments, presented in Chapter 2, established that introvertive anhedonia was associated with an executive functioning deficit that could be characterised as a deficiency in processing context. Chapter 3 presented a further three experiments indicating that introvertive anhedonia had blunted processing of negative and positive emotional cues, but under certain specific conditions a bias to the processing of negative stimuli. The final experiment, presented in Chapter 4, found that introvertive anhedonia was behaviourally insensitive to outcome valence changes of stimulus-outcome associations. The blunted processing of valenced stimuli seems to have influenced executive cognitive processes involved in both detecting the changes in outcome valence of associations and in forming new associations. An inability in introvertive anhedonia to adjust behaviour to changes in outcome valence might lead to perseveration, inappropriate responding and, in some situations, an over-exposure to aversive stimuli. The executive cognitive deficits observed in section two, and the emotion cue processing deficits observed in section three might therefore result form failures in common mechanisms.
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Edwards, Clementine Jane. "Anhedonia in schizophrenia : the roles of anticipatory and consummatory pleasure." Thesis, King's College London (University of London), 2016. https://kclpure.kcl.ac.uk/portal/en/theses/anhedonia-in-schizophrenia-the-roles-of-anticipatory-and-consummatory-pleasure(4c328300-9028-4fd0-9811-4db9aee97cab).html.
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The negative symptoms of schizophrenia, particularly anhedonia and amotivation, are associated with poor functioning and contribute to the chronicity of the illness. There are currently very few targeted interventions available for these difficulties. The Temporal Experience of Pleasure model suggests that there is a specific deficit in anticipatory pleasure in people with schizophrenia. However, studies in this field have produced conflicting results. The studies conducted had three broad aims. The first was to assess self-reported pleasure and its association with symptoms and mood. The second was to develop an experimental task that measured, for the first time, both anticipatory and consummatory pleasure using the same stimuli. This allowed a direct test of the hypothesis that there is a specific anticipatory pleasure deficit in people with schizophrenia. The final aim was to examine whether reduced anticipatory pleasure contributes to lower activity levels in everyday life. The results demonstrated that people with schizophrenia had comparable levels of anticipatory and consummatory pleasure to controls but a larger discrepancy between these ratings. Furthermore, anticipatory pleasure and expectation drive activity levels in the everyday life of control participants but these links were not present in people with schizophrenia. Positive affect was found to influence anticipatory pleasure across all three methodologies. These findings suggest that people with schizophrenia have difficulty translating anticipation into goal-directed activities. Positive mood may be an important contributor to anticipatory pleasure. The link between anticipation and activity may be an important therapeutic target for improvement in both negative symptoms and functional outcomes.
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Harrison, Amy. "Social anhedonia and work and social functioning in eating disorders." Thesis, King's College London (University of London), 2013. http://kclpure.kcl.ac.uk/portal/en/theses/social-anhedonia-and-work-and-social-functioning-in-eating-disorders(67fecf2d-8d91-407b-a03a-7971d8b2b9c4).html.
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Wright, Rebecca. "Anhedonia and other reward-related deficits in animal models of psychiatric disorder." Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/90987/.
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New insights have revealed the complex and heterogeneous nature of reward-related behaviours: not only are different aspects of reward (e.g. reward 'liking' and 'wanting') subserved by dissociable neural mechanisms, but they are differentially expressed across major psychiatric disorders. The aim of this thesis was to investigate discreet reward-related processes, pertaining to the hedonic and cognitive processing of rewards, in relation to schizophrenia and depression preclinical models. The Methylazoxymethanol acetate (MAM) neurodevelopmental model of schizophrenia and the Wistar Kyoto (WKY) inbred depression model were chosen based on their good face and construct validities to the clinical conditions. Microstructural analysis of licking in simple drinking and contrast situations were used to investigate the constructs of consummatory and anticipatory anhedonia in these models. Whilst MAM-treated rats showed no behaviours indicative of consummatory or anticipatory anhedonia, WKY rats showed generally lower consummatory and palatability responses to sweet solutions and failed to suppress their palatability responses to a contrasted solution (when a preferred solution was expected). Therefore, WKY rats demonstrated behaviours analogous to deficits in both consummatory and anticipatory aspects of hedonic processing. To investigate cognitive processing of rewards, outcome devaluation and differential outcome paradigms were adopted, but no impairments on either task were found for the MAM model. In contrast, WKY rats were insensitive to post-conditioning changes in reward value and did not benefit from stimulus-correlated outcomes during the acquisition of a conditional discrimination task. Therefore, WKY rats do not appear to use the nature and /or value of rewards to guide their behaviours in the same manner as controls. In short, MAM-treated animals did not display the hedonic deficits or impaired instrumental behaviours expected for a comprehensive schizophrenia model. In contrast, the WKY inbred rat strain appears to be suitable in investigating manifestations of clinical depression in respect to reward-processing deficits.
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Peeters, Corien. "The role of experience seeking, anhedonia, and affective disturbance in addictive behaviours." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ59193.pdf.
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Alvarez, Rojas Daniela Paz. "Anhedonia en perros: efecto del estrés sobre la preferencia frente a sacarosa." Tesis, Universidad de Chile, 2015. http://repositorio.uchile.cl/handle/2250/136219.
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Memoria para optar al Título Profesional de Médico VeterinarioLa anhedonia se describe como la disminución de la capacidad para sentir placer frente a diversas actividades, y se ha observado en humanos con ciertas patologías mentales. En otros mamíferos, como ratas y cerdos la anhedonia generada por estrés puede modificar el consumo de fuentes palatables como la sacarosa, cambiando sus preferencias. En el siguiente trabajo se estudió el efecto del estrés sobre la preferencia por sacarosa en perros. Se utilizaron 16 perros de 3–11 años, alojados en caniles, realizando pruebas de preferencia entre soluciones de sacarosa (10 g/L y 30 g/L) y agua durante 20 minutos, comparando las medias de consumo tras someter a la mitad de los animales a tres protocolos de bienestar: alimentación, paseo y enriquecimiento ambiental. Las pruebas previas a los protocolos experimentales arrojaron diferencias significativas en la preferencia según grupo etario, encontrándose mayor consumo de sacarosa 30 g/L y 40 g/L, con respecto a agua en perros adultos (≤6 años) (203,69 vs. 30,188 g. P=0,004 y 358,93 vs. 56,714 g. P=0,002), pero no en viejos (>6 años) (102,25 vs. 88,75 g. P=0,745 y 81,125 vs. 122,81 g. P=0,5), lo que podría deberse a la disminución en la percepción de los aromas en animales viejos. Sin embargo, no se observó efecto del estrés sobre las preferencias por sacarosa en ningún protocolo experimental, lo cual se condice con la alta variabilidad de resultados entre laboratorios. No obstante, esta conducta podría haberse observado con una menor variabilidad de factores intrínsecos y extrínsecos de los animales durante los ensayos, por lo que se recomiendan nuevos estudios complementarios para investigar la anhedonia en perros domésticos.
Fondo de Investigación en Ciencias Veterinarias 2014-2015
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Jell, Grace Elizabeth. "Understanding anhedonia : investigating the role of mind wandering in positive emotional disturbances." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/27942.
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Depression is a highly debilitating illness for which there is currently sub-optimal treatment outcomes. Anhedonia (a loss of interest and pleasure) is a core symptom of depression that predicts poorer illness course and is currently not well repaired in psychological treatments. Acute and relapse prevention outcomes may be improved by clarifying which psychological mechanisms cause and maintain anhedonia, so that mechanisms can be systematically targeted in therapy. Mind wandering (a shift in contents of thoughts away from an ongoing task and/or events in the external environment to self-generated thoughts and feelings) has previously been linked to lower levels of happiness in the general population (e.g., Killingsworth & Gilbert, 2010). However, it has yet to be established if mind wandering relates to reduced positive affect in the context of depression. Therefore, the purpose of this thesis was to further explore the role of mind wandering in driving anhedonic symptoms. This thesis employed different research designs in order to establish if mind wandering is a causal mechanism driving anhedonia. Studies used a triangulation of measures to first establish correlational support (e.g. using self-report questionnaire measures, laboratory and real life positive mood inductions). Following this, studies aimed to examine if a causal relationship between mind wandering and positive affect exists by manipulating levels of mind wandering in the laboratory, real-world settings and using an empirically tested clinical intervention (Mindfulness Based Cognitive Therapy; MBCT). Using self-report measures of mindfulness and anhedonic symptoms, studies 1a and 1b found that the acting with awareness facet of mindfulness (a measure of trait mind wandering) was uniquely related to anhedonic depression symptoms in both a large community (n=440) and treatment-seeking previously depressed sample (n=409). These unique relationships remained significant when controlling for other facets of mindfulness and general depression symptoms. Study 2 (n=70) examined the relationship between mind wandering and reduced positive affect in both controlled laboratory and real world environments. Levels of mind wandering were found to be unrelated to emotional reactivity to positive laboratory mood induction tasks, but greater levels of mind wandering were significantly correlated with reduced happiness and increased sadness change to real world positive events. Next, two experimental studies were conducted on unselected samples which attempted to manipulate levels of mind wandering to observe the effect on emotional reactivity. In study 3 (n=90), a brief mindfulness manipulation of mind wandering proved unsuccessful, so it was not possible to determine how altering mind wandering impacted on positive reactivity. Analysis during the pre-manipulation mood induction revealed a significant correlation between greater spontaneous levels of mind wandering and lower self-reported happiness reactivity. In study 4 (n=95), participants followed audio prompts delivered via a smartphone application to manipulate mind wandering whilst completing everyday positive activities. This manipulation was successful but results revealed no significant condition differences in positive or negative emotional reactivity. Analysis during the pre-manipulation positive activity revealed greater mind wandering was trend correlated with reduced change in positive affect. A final empirical study (study 5; n=102) was designed to investigate the mediating role of mind wandering on the effect of MBCT on change in positive emotional experience. Recovered depressed participants undertaking MBCT were compared to recovered depressed participants in a no-intervention control group. Correlational analysis pre-intervention revealed no support for an association between mind wandering and positive reactivity to the mood induction tasks but mind wandering measured during everyday life (using experience sampling methodology; ESM) did relate to lower positive affect and higher negative affect. Participants in the MBCT group demonstrated a reduction in trait and ESM mind wandering, relative to participants in the control group. Furthermore, participants in the MBCT group demonstrated a significant decrease in anhedonic symptoms and increase in daily levels of positive affect. Change in trait mind wandering was found to mediate changes in self-reported anhedonic symptoms when controlling for change in other mindfulness facets, however change in ESM mind wandering did not mediate change in daily positive affect. MBCT also had no impact on emotional reactivity to positive mood induction tasks. Overall the findings from this thesis provide correlational support for the link between mind wandering and reduced positive affect in different testing environments. However, evidence of a causal relationship is currently limited. Consequently, a key recommendation from this thesis is to redirect attention to other driving mechanisms as targeting mind wandering in the treatment of anhedonic clients is unlikely to lead to large improvements. The theoretical, methodological and clinical implications of these findings are discussed along with suggestions for future research.
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Kadison, Lisa. "Subtypes of anhedonia and facial electromyography response to negative affective pictures in healthy adults." Honors in the Major Thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/856.
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Flat affect (i.e., diminished expressivity) and self-reported anhedonia (i.e., lack of pleasure) are associated with many psychiatric disorders. There is a need to examine the relationship between specific anhedonia subtypes and flat affect in a non-clinical sample. Forty-seven undergraduate students (59% male; mean age 20.37; SD = 4.74) completed self-report questionnaires assessing four subtypes of anhedonia - consummatory/anticipatory by social/non-social. Participants then viewed 15 randomly-presented pictures (five neutral, ten negative) from the International Affective Pictures System while facial muscle activity (electromyography; EMG) was recorded. Male participants reporting a greater level of anhedonia, particularly consummatory social anhedonia, showed greater EMG activity change in the corrugator supercilii muscle to negative pictures, as compared with neutral pictures. Females showed the opposite pattern: more consummatory social anhedonia related to less EMG activity change in the corrugator muscle. In summary, consummatory social anhedonia in particular showed a strong relationship with facial expressivity that interacted with sex. In the presence of more consummatory social anhedonia, males show more negative facial reactions to negative stimuli while females show a more flattened affect. These findings may help explain discrepancies in existing research examining anhedonia and flat affect in clinical populations and have implications for etiology and treatments.B.S.
Bachelors
Sciences
Psychology
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Brauner, N. "Content-free cueing as a technique to inhibit mind wandering and treat anhedonia in depression." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1409970/.
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This thesis addresses the relationship between mind wandering and mood. Mind wandering is defined as a state of ‘decoupled attention’ removed from the immediate contexts towards unrelated thoughts and feelings (Smallwood & Schooler, 2006). Part one is a literature review that investigates the association between mind wandering and mood. It examines whether mind wandering affects mood and vice versa, and how mind wandering relates to mood disorder. Overall the findings were inconsistent. Gaps in the literature are highlighted and suggestions for future research are discussed. Part two consists of an empirical paper investigating if content-free cues in the form of auditory tones can reduce mind wandering and enhance mood. It furthermore examines if the beneficial effects of cuing are more pronounced in individuals with increasing depression severity. While cues led to a reduction in mind wandering in two laboratory tasks, this did not translate into pleasant every-day activities carried out at home. There was furthermore only weak support for the effects of cues on mood and contrary to predictions depression severity did not moderate the effects of cues. Limitations of the design and suggestion for further research are discussed along with clinical implications. Part three is a critical appraisal, which discusses the research designs, methods and testing and makes suggestions for future research. It closes with personal reflections on completing the thesis.
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Harvey, Philippe-Olivie. "Neural and cognitive correlates of anhedonia in non-clinical individuals and in people suffering from schizophrenia." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32537.
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The negative symptoms of schizophrenia, characterized as a loss or reduction of normal functions, have drawn a lot of attention in recent years in the research community. Negative symptoms are a multidimensional domain and constitute an unmet therapeutic need. The present research project focused on the negative symptom of anhedonia, defined as the reduced capacity to gain pleasure. It has been suggested that anhedonia characterizes a subgroup of patients with schizophrenia and represents a vulnerability marker for the development of schizophrenia when measured in non-clinical individuals. Moreover, there is evidence that self-report anhedonia severity in schizophrenia is influenced by neurocognitive deficits. For instance, schizophrenia is characterized by significant memory problems and evidence suggests a potential link with negative symptoms. The major goals of this project were: 1) to explore the relationship between emotional memory and self-report anhedonia severity; and 2) to identify brain alterations associated with inter-individual variability in anhedonia severity in people with schizophrenia and in non-clinical individuals. In a first behavioral study, we used an emotional recognition task to test whether anhedonia was linked to memory performance for emotional face expressions. Results suggest that self-report anhedonia severity in schizophrenia is not directly influenced by emotional memory deficits. The neuroimaging studies first involved the design of a magnetic resonance imaging paradigm using complex emotional pictures. This paradigm allowed us to measure brain activity associated with the processing of hedonic information. We first found that elevatIl y a un intérêt croissant chez les chercheurs pour l'étude plus approfondie des symptômes négatifs de la schizophrénie. Les symptômes négatifs, définis comme une perte ou une réduction du fonctionnement normal de l'individu, ont une nature multidimensionnelle et constituent un défi clinique, tant au niveau des traitements pharmacologiques que psychologiques. Ce projet de recherche de doctorat s'est concentré plus particulièrement sur le symptôme négatif de l'anhédonie, définie comme une réduction de la capacité à ressentir le plaisir. Des études antérieures suggèrent que l'anhédonie pourrait caractériser un sous-groupe distinct de patients schizophrènes. Certains chercheurs ont aussi démontré que ce symptôme peut représenter un marqueur de vulnérabilité pour le développement de la schizophrénie lorsque détecté dans une population non-clinique. Il y a finalement l'hypothèse que la sévérité de l'anhédonie dans la schizophrénie, telle que mesurée par des auto-questionnaires ou des entrevues cliniques, est modulée par des déficits neurocognitifs. Les buts principaux de ce projet de recherche étaient: 1) d'explorer la relation entre la mémoire émotionnelle et la sévérité de l'anhédonie auto-rapportée; et 2) d'identifier les altérations cérébrales associées à la variabilité inter-individuelle au niveau de la sévérité de l'anhédonie, et ce dans une population non-clinique ainsi que dans un groupe de patients schizophrènes. Dans une première étude comportementale, nous avons utilisé une tâche mnésique de reconnaissance émotionnelle afin de tester si l'anhédonie était liée, d'une part, à la performance$
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Kalmbach, David A. "SPECIFICITY OF ANHEDONIC DEPRESSION AND ANXIOUS AROUSAL WITH SEXUAL PROBLEMS, AND THE VALIDATION OF SEXUAL FUNCTIONING MEASURES AMONG HEALTHY MALES AND FEMALES." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1308590687.
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Bell, Emily K. "Assessing schizoid asociality in schizophrenia: determining the construct validity of two self-report scales." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1405606546.
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Leung, Winnie W. "Experience and expression of emotion in social anhedonia an examination of film-induced social affiliative state in schizotypy /." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3843.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2006.Thesis research directed by: Psychology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Burrows-Kerr, Ruth. "Repetitive negative thought and anhedonia : a systematic review (literature review) ; Repetitive negative thought and reward sensitivity (empirical paper)." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/18074.
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Literature Review: Anhedonia, the loss of interest or pleasure in usually pleasurable activities, is a core symptom of depression and is associated with a reduction in positive affect (PA). Repetitive negative thought (RNT) is implicated in the development and maintenance of psychiatric disorders. It has been hypothesised that RNT causally contributes to anhedonia. The aim of this review was to explore this relationship to answer two questions: Is there a relationship between RNT and anhedonia? Does RNT causally contribute to anhedonia? Review inclusion criteria were: studies using standardised measures to report a relationship between RNT and anhedonia or reduced PA. Results suggest that cross-sectional and longitudinal studies identify a relationship between RNT and anhedonia. Preliminary evidence from experimental studies shows that RNT causally contributes to anhedonia. Limitations within the field are that anhedonia is rarely measured directly or behaviourally. Future research is warranted to explore the relationship between RNT and anhedonia with a particular focus on direct and behavioural measures of anhedonia. Empirical Paper: It is hypothesised that repetitive negative thought (RNT) causally contributes to anhedonia. There is cross-sectional and longitudinal evidence of this relationship, but it has not previously been investigated directly using experimental methods. In the present study, student participants were randomly assigned to an unresolved goal (RNT) manipulation (n = 43) or resolved goal (control) manipulation (n =41) prior to completing a reward sensitivity task. This task has been reliably found to train a response bias towards the stimuli that is differentially positively reinforced, with both depression and self-reported anhedonia associated with a reduced response bias. The unresolved goal versus resolved goal manipulation was effective, with the unresolved condition producing significantly higher levels of RNT during the reward sensitivity task relative to the resolved condition. Inconsistent with study predictions, there was no significant difference between the conditions on response bias, although there were trend findings, which tentatively suggest that RNT may influence anhedonia. Potential accounts for the null findings and future research are discussed.
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Cooper, Shanna. "EXPERIENTIAL NEGATIVE SYMPTOMS IN YOUNG ADULTS ENDORSING PSYCHOTIC-LIKE EXPERIENCES." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/517180.
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PsychologyPh.D.
While many studies of risk factors for psychosis focus on positive symptoms, such as subthreshold levels of hallucinations and delusions, fewer studies have examined negative symptoms in the early course of the schizophrenia or other psychotic disorders. This relative lack of focus on the role of negative symptoms is problematic, given findings that negative symptoms, such as a loss of motivation and pleasure (MAP), are associated with a more persistent and impairing course of psychosis, and tend to appear earlier in the development of psychotic symptoms. Psychotic disorders, which afflict approximately 3-5% of the population, tend to emerge in late adolescence/early adulthood and are among the most debilitating and costly of mental disorders. The current project explored three areas of negative symptoms in young adults who demonstrated a range of psychotic-like experiences (PLEs). First, a review of the literature pertaining to negative symptoms across the span of psychosis was conducted. Second, we tested whether experiential negative symptoms – specifically MAP deficits – were associated with increases in PLEs, including those that are experienced as distressing (PLEDs). Third, we examined the potential influence of episodic memory performance factors on the relationship between MAP symptoms and PLEs/PLEDs. Collectively, this project highlights the importance of including negative symptoms (i.e., MAP deficits) and/or cognitive performance (i.e., associative/relational learning/memory) outcomes when evaluating people with PLEs/PLEDs to identify those who may be at greater risk for developing a psychotic disorder.
Temple University--Theses
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Alkhlaif, Yasmin. "IMPACT OF CHEMOTHERAPY ON NICOTINE DEPENDENCE." VCU Scholars Compass, 2017. https://scholarscompass.vcu.edu/etd/5175.
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Although cigarette smoke has been implicated in a causal relationship with various types of cancers, around 62% of all cancer patients are current smokers, recent quitters, or former smokers. While most patients who are smokers are motivated to quit after cancer diagnosis, 25 -30% of these patients continue to smoke. Furthermore, most quitters relapse after 2-3 years of post-chemotherapy. This represents a major health concern since several clinical studies revealed that perpetuation of smoking in cancer populations attenuates patient's well-being and quality of life. Smoking may impair healing, attenuate the efficacy of chemotherapy, increase the disease complications and diminish survival rates. However, the factors that involved in nicotine dependence in cancer patients are poorly understood. xii According to human research, it was suggested that tumor site, impact of cancer therapy and disease prognosis could be responsible of continuation of tobacco smoking among cancer patients and survivors. Recently, chemotherapy was shown to cause emotional deficits in humans (anxiety, insomnia and depression) and animals. In this project, we focused on the chemotherapeutic agent, paclitaxel, because it is widely used to treat solid tumors such as lung, head, neck and breast cancer. We previously reported that paclitaxel induced general affective deficits in mice such as anhedonia, anxiety and depression-like behaviors. We therefore hypothesized that the chemotherapeutic agent, paclitaxel may alter the rewarding and withdrawal properties of nicotine. We investigated the impact of paclitaxel on spontaneous nicotine withdrawal and nicotine reward in C57BL/6J mice by using variety of behavioral tests. Our findings showed that paclitaxel worsened the somatic and affective signs of nicotine withdrawal in male mice as well as attenuated of nicotine reward in the CPP assay. These behavioral changes were not due to an impact of nicotine metabolism by paclitaxel. Overall, paclitaxel changed the behaviors during nicotine withdrawal and reward and that suggested changing in the smoking behavior after exposure to chemotherapy.
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Szebeni, Attila, Katalin Szebeni, Timothy P. DiPeri, Luke A. Johnson, Craig A. Stockmeier, Jessica D. Crawford, Michelle J. Health Sciences Chandley, et al. "Elevated DNA Oxidation and DNA Repair Enzyme Expression in Brain White Matter in Major Depressive Disorder." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/943.
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Background: Pathology of white matter in brains of patients with major depressive disorder (MDD) is well-documented, but the cellular and molecular basis of this pathology are poorly understood.
Methods:Levels of DNA oxidation and gene expression of DNA damage repair enzymes were measured in Brodmann area 10 (BA10) and/or amygdala (uncinate fasciculus) white matter tissue from brains of MDD (n=10) and psychiatrically normal control donors (n=13). DNA oxidation was also measured in BA10 white matter of schizophrenia donors (n=10) and in prefrontal cortical white matter from control rats (n=8) and rats with repeated stress-induced anhedonia (n=8).
Results:DNA oxidation in BA10 white matter was robustly elevated in MDD as compared to control donors, with a smaller elevation occurring in schizophrenia donors. DNA oxidation levels in psychiatrically affected donors that died by suicide did not significantly differ from DNA oxidation levels in psychiatrically affected donors dying by other causes (non-suicide). Gene expression levels of two base excision repair enzymes, PARP1 and OGG1, were robustly elevated in oligodendrocytes laser captured from BA10 and amygdala white matter of MDD donors, with smaller but significant elevations of these gene expressions in astrocytes. In rats, repeated stress-induced anhedonia, as measured by a reduction in sucrose preference, was associated with increased DNA oxidation in white, but not gray, matter.
Conclusions:Cellular residents of brain white matter demonstrate markers of oxidative damage in MDD. Medications that interfere with oxidative damage or pathways activated by oxidative damage have potential to improve treatment for MDD.
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Sandt, Arthur Ralph. "Hedonic Functioning and Subthreshold Psychotic Symptoms." Diss., Temple University Libraries, 2013. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/164124.
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PsychologyPh.D.
Schizophrenia is a debilitating disorder with an array of affective, cognitive, and behavioral consequences. In addition to these impairments, research suggests that there is a distinct pattern of hedonic functioning in schizophrenia that may contribute to some of the most intractable symptoms of the disorder, the negative symptoms. Specifically, individuals with schizophrenia appear to experience deficient levels of pleasure during anticipation of a pleasurable stimulus, while experiencing typical levels of pleasure while directly engaged with a pleasurable stimulus. Despite these findings, it is unclear whether hedonic functioning deficits occur in individuals with subthreshold levels of psychotic symptoms and/or in individuals at clinical high risk for the disorder. The purpose of this study was to examine hedonic functioning in relation to the continuum of psychotic symptoms in a college undergraduate student sample, and in those at clinical risk for schizophrenia. Participants were 679 students who completed self-report measures of current psychotic-like experiences, and trait-like components of hedonic functioning (i.e., anticipatory and consummatory pleasure). Consistent with study hypotheses, deficits in anticipatory pleasure, but not in consummatory pleasure, were significantly associated with increased clinical risk for schizophrenia. However, this relation was found exclusively among women in the sample, whereas men did not show a significant relation between anticipatory pleasure deficits and clinical high-risk. Furthermore, anticipatory pleasure deficits were not significantly associated with increases in the number of positive psychotic symptoms endorsed. Moreover, consummatory pleasure was not associated with increases in the number of subthreshold positive psychotic symptoms, nor was there a relation with the number of distressing positive psychotic symptoms or clinical risk status. The present study provides the first examination of the relation between hedonic functioning and subthreshold psychotic symptoms, as well as the relation with clinical high-risk for psychosis. These findings suggest that anticipatory pleasure deficits may be more closely related to increased clinical risk for psychosis among women rather than increases in psychotic symptoms in the general population. Anticipatory pleasure deficits may be a useful target for intervention and prevention techniques among those at clinical risk for psychosis, especially in female at risk populations. Additional longitudinal studies will be essential for testing whether anticipatory pleasure deficits predict the occurrence of future psychotic disorders among those at high risk for the disorder in order to improve early identification and early intervention efforts in this population.
Temple University--Theses
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Martin-Iverson, Mathew Thomas. "The effect of a dopamine antagonist and an agonist on rats’ perception of reward quantity : an examination of the anhedonia hypothesis." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25938.
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A procedure was developed to determine the effect of a dopamine (DA) antagonist (haloperidol) and a DA agonist (d-amphetamine) on rats' perceptions of the hedonic value of food. Eighteen rats were trained to discriminate between two quantities of sweet food pellets (1 and 4), in a forced-choice two-lever successive discrimination procedure. To control for non-specific perceptual effects of the treatments, the rats were also trained to discriminate between 1 and 4 tones.
It was established that rats attended to the value of food, as well as the proportional differences in quantity, when discriminating food quantities. This was accomplished by altering the value of the food in two ways. Firstly, "hunger" was altered by changing the degree of food deprivation during testing. Secondly, unsweetened food pellets were introduced as probe cues. These two methods of altering the value of food pellets were utilized while quantity generalization gradients were determined, by presenting animals with 1,2, 3 and 4 numbers of stimuli as probe cues. Two measures were derived from these generalization gradients: the point of subjective equality (PSE), which is the calculated number of stimuli that would maintain responses equally distributed between the two levers, and the slope of the gradient. The PSE primarily reflects perceptual processes, while the slopes of the gradients provide an index of performance impairment. It was observed that decreasing the value of food by either decreasing food deprivation or reducing the sweetness of the food pellets resulted in the rats perceiving a given quantity of food as larger than before these treatments (decreased the food PSE). Neither altering food deprivation nor introducing novel tone probes had an effect on the numerical attributes of tones, as reflected by the tone PSE.
Haloperidol (0.030, 0.50 and 0.083 mg/kg, i.p.) produced a statistically significant, but slight dose-dependent performance deficit, as reflected by the slope of the generalization gradients. It did not affect the perception of food pellet quantities at any dose, as reflected by the food PSE. Haloperidol decreased the number of tones a given quantity was perceived as by rats (increased the tone PSE). Amphetamine (0.25, 0.50 and 1.0 mg/kg, i.p.) decreased the perception of a given quantity of food (increased the food PSE) in a dose-dependent manner, without a significant effect on performance. Thus, amphetamine enhanced the hedonic value of food. Amphetamine also increased rats' perceptions of a given number of tones (decreased the tone PSE).
It therefore appears that while d-amphetamine can enhance the perceived hedonic value of food, haloperidol has no effect on rats' perceptions of the hedonic value of food. Furthermore, evidence that DA systems are involved in the mechanism of an "internal clock" or "counter" was obtained.Medicine, Faculty of
Graduate
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Craft, Tara K. S. "Psychological determinants of stroke outcome in mice." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1150315601.
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Copestake, Claudia Catarina. "The impact of experiential avoidance on reduced positive emotional responsivity in post traumatic stress disorder." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/15419.
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Experiential avoidance (EA), or the evasion of unpleasant internal experiences, is key to changes in emotional responsivity in Posttraumatic Stress Disorder (PTSD). EA has been linked to altered negative emotional reactivity in PTSD, but it remains unclear whether EA is linked to altered positive reactivity in PTSD, i.e. anhedonia. Therefore the study examined how manipulating EA influences emotional responsiveness in a non-clinical adult population (N=74). Positive emotion reactivity (self-report and psychophysiology) was measured before and after viewing a laboratory analogue trauma induction, with half of participants instructed to adopt the detached protector (DP) mode as an example of EA during trauma viewing and half of participants in an uninstructed control condition. Following the DP mode instructions reduced negative emotion experience during the trauma induction, relative to the control condition. However counter to prediction, there was no carry over onto blunted positive emotion experience or psychophysiological response in the experimental condition (relative to the control condition) when recalling positive memories and imagining positive future events. No significant relationships were identified between trait EA levels and anhedonia symptoms or pre-manipulation positive emotional responsiveness in the laboratory. Overall, the current findings offer no support for the hypothesis that EA contributes to anhedonia.
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Morris, Bethany H. "The Effect of Stress on Hedonic Capacity in Generalized Anxiety Disorder: A Prospective Experimental Study of One Potential Pathway to Depression." Scholar Commons, 2009. https://scholarcommons.usf.edu/etd/1716.
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A growing body of work links psychopathology to changes in hedonic capacity following stressors. This was the first experimental study of the effects of stress on hedonic capacity in an analog generalized anxiety disorder (GAD) sample (a high worry group). Specifically, we utilized an experimental manipulation of stress and a behavioral index of anhedonia to test the hypothesis that individuals with GAD, who are at higher risk for developing depression symptoms, exhibit greater stress-related deficits in hedonic capacity than do nonanxious controls. Further, this study assessed whether stress-induced hedonic deficits predicted future depression. Controls exhibited the expected reward learning pattern in the baseline condition, demonstrating intact hedonic responding, as well as the expected pattern of behavioral anhedonia under stress. Contrary to predictions, worriers demonstrated intact hedonic capacity under stress. The stress effect in worriers was modulated by past depression diagnostic status; whereas worriers with no past depression demonstrated blunted baseline hedonic capacity and heightened hedonic capacity under stress, worriers with past depression demonstrated the normative response pattern. Blunted baseline response bias predicted higher future depression in both groups. We discuss the differential stress effects on behavioral hedonic capacity found as a function of worry, the role of past depression as a moderator of stress effects among worriers, and the need for future work to further explicate the mechanisms that may modulate reward response under stress.
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Thomaz, Cassia Roberta da Cunha. "Possíveis inter-relações entre a submissão ao Chronic Mild Stree(CMS) e o desempenho operante." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/47/47132/tde-26112009-135126/.
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Chronic Mild Stress (CMS) é um modelo animal de depressão no qual ratos são submetidos a um protocolo de estressores moderados de forma crônica. Em função disso, o consumo e preferência por água com sacarose diminuem. Tal redução costuma ser considerada uma medida de anedonia, sintoma central da depressão em humanos. Três estudos realizados no Laboratório do Programa de Estudos Pós- Graduados em Psicologia Experimental da PUC-SP demonstraram que esse efeito é atenuado pela exposição a uma condição operante em esquema concorrente FR água FR sacarose. O presente estudo teve por objetivo investigar se a submissão a uma condição operante que envolvesse diferentes estímulos reforçadores teria o mesmo efeito. Para isso, as seguintes condições experimentais foram propostas: 1) exposição a um protocolo de estressores por seis semanas; 2) testes semanais de consumo de água e água + 2% sacarose; 3) sessões operantes. Dos nove sujeitos utilizados, quatroforam expostos também a uma condição na qual a resposta de pressão à barra foi consequenciada com acesso à roda de atividades, dois a uma condição na qual a resposta de pressão à barra foi consequenciada com uma pelota de alimento em FR6 e dois em FR12. Como resultado, observou-se que no sujeito submetido somente aos estressores (sujeito 09) foi replicado mais uma vez o efeito de redução no consumo de solução de sacarose. Esse efeito não pode ser observado em nenhum dos sujeitos submetidos às sessões operantes durante a exposição. Observou-se uma queda somente no primeiro teste após o término dessa, indicando que possivelmente a submissão a essas afetou o efeito tradicionalmente observado em decorrência da exposição ao protocolo de estressores. Tais resultados corroboram e ampliam os estudos anteriores. Nas sessões operantes, observou-se redução na taxa de respostas na quinta semana de exposição para os sujeitos em FR12 (02 e 03) e na quinta ou sexta para o sujeitos em FR6 (01 e 04). O desempenho na roda de atividades pareceu ficar sob controle da alteração no peso corporal (sujeitos 05 a 09). É possível que a exposição à condição operante tenha atenuado os efeitos do protocolo de estressores e a redução no valor reforçador dos estímulos tenha sido retardada e/ou observada em condições com maior custo de resposta.Chronic Mild Stress (CMS) is an animal model of depression. Chronic exposure of rats to a protocol of mild stressors produces decrease in sucrose intake and reduction in the preference for sucrose over water, which is considered as a measure of anhedonia, a core symptom of depression. Three Brazilian studies from PUC-SP showed that the additional exposure of rats to operant sessions using FR water FR sucrose concurrent schedule of reinforcement attenuates this effect. The objective of this study was to investigate if the submission to operant conditions that involves other reinforcers would also attenuate the decrease in sucrose consumption. Three experimental conditions were proposed: 1) exposure to a protocol of mild stressors for six weeks; 2) weekly tests of water and water + 2% sucrose intake; 3) operant sessions. Subject 09 was exposed only to conditions (1) and (2). Eight subjects were submitted to conditions (1), (2) and (3): access to a running-wheel served as reinforcer, in CRF, for subjects 05, 06, 07 and 08 and food was the reinforcer for other four subjects: 01 and 04 were submitted to a FR6 schedule of reinforcement and 02 and 03 to a FR12 schedule of reinforcement. It was observed that the subject 09, that was submitted only to stressors showed, again, a decrease in sucrose consumption and preference. The other eight subjects did not show this effect. A decrease in sucrose consumption was noted only in the first test after exposure to the protocol. These results suggest that submission to these operant conditions affected the traditional effect of the exposure to mild stressors and it corroborates and amplifies previous studies. During operant conditions, it was observed that lever presses decreased during fifth week of exposure to stressors for subjects responding on FR12 and during fifth or sixth week for subjects responding on FR6. Performance on running wheel changed according to body weight. It is possible that exposure to these operant conditions diminished the stressors effects and that the decrease in the reinforcing value of these stimuli was delayed and/ or observed under conditions with higher response cost.
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Keränen, A. M. (Anna-Maria). "Lifestyle interventions in treatment of obese adults:eating behaviour and other factors affecting weight loss and maintenance." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514294457.
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Abstract The prevalence of working-aged weight losers is high because of high prevalence of obesity. Unfortunately, the loss of weight is often temporary. The aim of the present study was to investigate the effect of intensive counselling on maintained weight loss and eating behaviour (cognitive restraint, emotional eating, uncontrolled eating and binge eating). Additionally, the associations of eating behaviour with maintained weight loss, discontinuation, dietary intake and anhedonia were studied. Eighty-two overweight or obese subjects (body mass index >27) participated in either intensive (n=35) or short-term (n=47) weight loss counselling (based on the Finnish Current Care guidelines) in a randomized weight loss follow-up study lasting 18 months. The subjects in the intensive counselling group lost more weight than those in the short-term counselling group at the 6 months follow-up (5.0±5.7kg, 2.4±2.5kg, respectively). The weight loss results were not maintained in either of the groups. The cognitive restraint increased and the emotional eating, uncontrolled eating and binge eating symptoms decreased in both groups. There were subjects in both counselling groups who succeeded in weight loss (weight loss result 9.3±6.3%) and those who failed (gained 3.3±1.7% of body weight). Those who succeeded had the highest score for cognitive restraint and lowest for uncontrolled eating, binge eating and emotional eating. In failure group, the scores for uncontrolled eating and binge eating were the highest already at the beginning of study. Those with the highest cognitive restraint at 18 months reported low intake of energy and fat while their intake of carbohydrates and fibre was high. Anhedonia existed in 24.4% of the participants at least once during the study period. They had higher binge eating scores continously, more uncontrolled eating and emotional eating at 6 months and they lost less weight than those without anhedonia. Thirty-two participants (39%) discontinued the study. Discontinuation was independently associated with a lack of free-time and a high weight loss goal. The association of eating behaviour with weight loss and dietary intake suggest that enhancing eating behaviour could be a target for improving the success of weight loss. The assessment and then the treatment of psychological factors (such as anhedonia), focus on setting realistic weight loss targets as well as emphasizing the fact that counselling visits and lifestyle changes are time consuming processes should be included in weight loss counsellingTiivistelmä Lihavuuden lisääntyessä myös työikäisten laihduttajien määrä kasvaa. Laihdutustulos jää valitettavan usein väliaikaiseksi. Tämän työn tavoitteena oli tutkia tehostetun ohjauksen vaikutusta laihtumistulokseen ja syömiskäyttäytymiseen (tietoinen syömisen hillintä, tunnesyöminen, impulsiivinen syöminen ja ahmimistaipumus). Lisäksi tutkittiin syömiskäyttäymisen yhteyksiä laihtumistulokseen, tutkimuksen keskeyttämiseen, energiaravintoaineiden saantiin sekä anhedoniaan. Tutkimukseen osallistui 82 ylipainoista tai lihavaa henkilöä (painoindeksi >27kg/m2). Heidät satunnaistettiin kahteen tutkimusryhmään: tehostetun ohjauksen (n=35) ja lyhytohjauksen ryhmään (n=47). Ohjaus perustui aikuisten lihavuuden Käypä hoito -suositukseen. Tutkimuksen kesto ohjaus- ja seurantajakson kanssa oli 18 kuukautta. Tehostetun ohjauksen ryhmässä henkilöt laihtuivat ensimmäisen kuuden kuukauden aikana enemmän kuin lyhytohjausryhmässä (5.0±5.7kg ja 2.4±2.5kg). Laihtumistulos ei kuitenkaan ollut pysyvä. Syömiskäyttäytymisessä tapahtui pysyvä muutos kummassakin tutkimusryhmässä; tietoinen hillintä lisääntyi, ja samanaikaisesti tunnesyöminen, impulsiivinen syöminen ja ahmiminen vähenivät. Kummassakin ryhmässä oli laihtumisessa onnistuneita (laihtumistulos 9.3±6.3 %) sekä epäonnistuneita (paino nousi 3.3±1.7 %). Onnistujilla esiintyi enemmän tietoista syömisen hillintää ja samanaikaisesti vähiten tunnesyömistä, impulsiivistä syömistä ja ahmimistaipumusta. Epäonnistujat söivät jo alkutilanteessa impulsiivivisemmin, ja heillä oli enemmän ahmimistaipumusta kuin onnistujilla. Henkilöt, joilla oli korkein tietoinen syömisen hillintä, saivat vähiten energiaa ja rasvaa mutta eniten hiilihydraatteja ja kuitua. Anhedoniaa esiintyi 24.4 %:lla tutkituista ainakin kerran tutkimuksen kuluessa. Anhedoniaan yhdistyi myös muita korkeammat ahmimistaipumuspisteet koko tutkimuksen ajan, eniten impulsiivista syömistä ja tunnesyömistä kuuden kuukauden seurannassa ja vähäisempi laihtuminen kuin henkilöillä, joilla ei esiintynyt anhedoniaa. Tutkimuksen keskeytti 39 % mukaan lähteneistä. Keskeyttämisen itsenäisiä riskitekjöitä olivat vapaa-ajan puute ja suuri laihtumistavoite. Syömiskäyttäytymisen yhteys sekä laihtumiseen että energiaravintoaineiden saantiin osoittaa, että syömiskäyttäytymisen ohjaus tulisi olla keskeinen osa laihdutusohjausta. Myös ahedonian arviointi ja hoito sekä keskustelu realistisesta painotavoiteesta ja elämäntilanteen kuorimittavuudesta voisivat tehostaa laihdutuksen onnistumista
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Oliver, Jason A. "Effects of Nicotine Withdrawal on Motivation, Reward Sensitivity and Reward-Learning." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5754.
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Research on addictive behavior has traditionally emphasized the role that primary reinforcing effects of drugs of abuse plays in the development and maintenance of dependence. However, contemporary behavioral economic theory and animal models of nicotine dependence suggest the need for greater attention to the impact that response to alternative rewards may have on smoking behavior. The present study sought to investigate the impact of nicotine withdrawal on self-report, behavioral and neural indices of motivation, immediate response to rewards and the capacity to learn and modify behavior in response to positive and negative feedback. Heavy smokers (n = 48) completed two laboratory sessions following overnight deprivation, during which they smoked either nicotinized or denicotinized cigarettes. At each session, they completed a reward prediction and feedback learning task while electro-encephalographic recordings were obtained, as well as resting state recordings which were used to extract global indices of motivational state. Results confirmed that nicotine withdrawal produced an avoidant motivational state. This effect was strongly related to numerous indices of smoking motivation. Exploratory analyses also revealed numerous moderators of these effects. Behavioral data from tasks provided some support for the impact of nicotine withdrawal on reward and feedback processing, though minimal impact was observed for neural indices. Together, results confirm the manifestation of a broad-spanning impact of nicotine withdrawal on motivational state, but effects on specific reward systems remains unknown. Future research should examine the impact of nicotine withdrawal on other reward-related constructs to better delineate these effects.
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Silva, Paulo Eduardo da. "Efeitos do protocolo de estressores em ratos submetidos a um regime contínuo de privação de água." Pontifícia Universidade Católica de São Paulo, 2015. https://tede2.pucsp.br/handle/handle/16753.
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The Chronic Mild Stress (CMS) has been described in the literature as an experimental model of anhedonia, central symptom of depression in humans. The anhedonia has been studied in this model looking for a decrease of water with sucrose consumption in rats. This result is usually observed after the animal had been subjected to a set of stressful stimuli in a moderated and chronical way, for six weeks in average. The present study aimed to investigate the effects of the Stressors Protocol in rats subjected to a continuous water deprivation regimen. Eleven male rats of Wistar lineage were studie,. All the rats were subjected to a water deprivation schedule until reaching 85% of their ad lib weights, and they were maintained at these weights for the whole study. Thirteen water and water with sucrose consumption tests were used for all the subjects, while S7 was exposed only to the liquids consumption tests. S3 subject was submitted only to the Stressors Protocol. S5 was exposed to the same conditions of S3, except that the Stressors Protocol involved only the grouping stressor. For the other eight subjects, first they had the bar press response to the two bars modeled, using water as reinforcement. Then these eight animals were subjected to a Conc VI 5 sec VI 5 sec reinforcement, each bar being associated to water or water with sucrose reinforcements (one for each bar). After four weeks in this reinforcement schedule these animals were subjected to the Stressors Protocol for six consecutive and uninterrupted weeks in their living cages. During the protocol, four subjects (S2, S6, S8 and S10) also had their bar press responses reinforced in a Conc VI 5 sec VI 5 sec schedule (group before, during and after). The other four rats (S1, S4, S9 and S11- group before and after) were not submitted to operant sessions as long as the Stressors Protocol was available. At the end of the phase when the Stressors Protocol was available, these eight subjects were again subjected to the base line condition. The main results were: (a) a weight stability for the animals subjected to the protocol, (b) a high alternation of water and water with sucrose consumption in the tests for the only subject submitted to the tests and to the protocol, not demonstrating anhedonia, (c) a reduction in the animal s food consumption and an increase of water consumption in the living cage during the protocol for seven subjects, (d) the stressors protocol was not followed by a modification of the distribution of water and water with sucrose reinforced responses by Conc VI 5sVI5s, neither during the protocol, nor after its cessation, and (e) it seems that the reinforcement value of the liquids alternated for some subjects over major of the sessions. The role of continuous water deprivation and the measures used as anhedonia indicators are discussed
O Chronic Mild Stress (CMS) tem sido descrito na literatura como um modelo experimental de anedonia, sintoma central na depressão em humanos. A anedonia tem sido estudada dentro desse modelo a partir do decréscimo no consumo de água com sacarose em ratos. Este resultado é geralmente observado após o animal ser submetido a um conjunto de estímulos estressores de forma moderada e crônica, durante seis semanas em média, O presente estudo teve como objetivo investigar os efeitos do Protocolo de Estressores em ratos submetidos a um regime contínuo de privação de água. Foram empregados 11 ratos machos, da linhagem Wistar. Todos os sujeitos foram submetidos a um esquema de privação de água até atingir 85% dos seus pesos ad lib. e foram mantidos nesses pesos durante todo o estudo. Foram empregados 13 testes de consumo de água e de água com sacarose, sendo que o Sujeito S7 só passou pelos testes de consumo dos líquidos. O Sujeito S3 foi submetido ao Protocolo de Estressores. O sujeito S5 passou pelas mesmas condições que o S3, exceto que o Protocolo de Estressores envolveu apenas o estressor agrupamento. Para os outros 8 sujeitos, primeiramente foram modeladas as respostas de pressão às duas barras, usando água como reforçador. Depois, esses 8 animais foram submetidos a um esquema Conc VI 5 seg VI 5 seg associado aos reforços água e água com sacarose (um para cada barra). Após quatro semanas nesse esquema de reforçamento esses animais foram submetidos ao Protocolo de Estressores por seis semanas consecutivas e ininterruptas nas suas gaiolas-viveiro. Durante o Protocolo, 4 sujeitos (S2, S6, S8, S10) também tiveram suas respostas de pressão à barra reforçadas num esquema Conc VI 5 seg VI 5 seg (grupo antes, durante e depois) e os outros 4 (S1, S4, S9, S11) não (grupo antes e depois). Ao término do Protocolo de estressores, esses 8 sujeitos foram submetidos novamente à condição de linha de base. Os principais resultados encontrados foram: (a) estabilidade nos pesos dos animais submetidos ao protocolo, (b) maior oscilação em relação ao consumo de água e de água com sacarose para o sujeito submetido apenas aos testes e ao protocolo, não demonstrando anedonia, (c) redução no consumo de ração e aumento no consumo de água na gaiola-viveiro durante o protocolo (d) o protocolo de estressores não foi acompanhada por uma alteração na distribuição de respostas reforçadas com água e água com sacarose, nem durante e nem após a suspensão do mesmo, e (e) o valor reforçador dos líquidos parece ter se alternado para alguns sujeitos ao longo da maioria das sessões. Discute-se o papel da privação contínua de água e as medidas utilizadas como indicativas a de anedonia
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Bloodworth, Natasha Louise. "Approach motivation, goal pursuit, and reward-related neural responses : a combined experience-sampling and fMRI approach." Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/27590.
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This thesis examines potential associations between trait approach motivation and related measures, the everyday experience of affect and goal pursuit, and reward-related neural responses. The Behavioural Activation System (BAS) is a core motivational system, subserved by the neural reward circuitry, eliciting approach-type behaviour and positive emotion when activated by appetitive stimuli. Deficits in BAS sensitivity are thought to underlie the lack of motivation and positive affect (PA) that characterise anhedonia, whilst hyperactivation of the BAS has been linked to the increased goal-directed behaviour and positive affectivity associated with hypomania. In order to explore relationships between BAS sensitivity, goal pursuit, and reward processing, young participants, recruited from the student population (N = 65), and older participants, from the community (N = 63), underwent a 7-day period of experience sampling (ESM) to provide a naturalistic measure of momentary affect and goal-focused motivation. Functional Magnetic Resonance Imaging (fMRI; in a subset of n = 28 and n = 31 respectively) was then used to investigate individual differences in sensitivity of brain reward-related systems to various social and non-social rewards. Limited support was found for the relationship between BAS traits and the more motivational aspects of goal pursuit and reward processing, whilst anhedonia seemed to pertain more to reward consumption, with few links to everyday goal pursuit. This would indicate that anhedonia might not be as closely related to BAS sensitivity as was initially anticipated. Finally, in order to examine real-world correlates of neural activation, the data from the naturalistic measure were correlated with reward-related activation. Everyday PA correlated with striatal activation when viewing pleasant images, but no other associations emerged. This would suggest that the basic measures of brain function in relation to the particular reward-related stimuli used might be of limited relevance to everyday affective experience and goal pursuit.
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Alexander, Laith. "Primate ventromedial prefrontal cortex and the physiological and behavioural dysfunction characteristic of mood and anxiety disorders." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/288429.
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The heterogeneity intrinsic to the ventromedial prefrontal cortex (vmPFC) is evidenced in both its anatomy and implicated function: vmPFC subregions have roles in positive affect, negative affect and autonomic/endocrine regulation. Whether different subregions serve fundamentally different functions, or whether they perform similar computations on different inputs, remains unclear. Nevertheless, the role of the vmPFC in psychopathology is widely appreciated - in mood and anxiety disorders, over-activity within constituent regions of the vmPFC is consistently implicated in symptomatology, together with its normalisation following successful treatment. However, the precise locus of change varies between studies. The work presented in this thesis investigates the causal contributions of over-activity within two key subregions of the vmPFC - the subgenual anterior cingulate cortex (sgACC, area 25) and perigenual anterior cingulate cortex (pgACC, area 32) - in discrete dimensions of behaviour and physiology affected in psychiatric disorders. Specifically, the impact of over-activity is assessed on (i) baseline physiological function; (ii) the regulation of anticipatory, motivational and consummatory aspects of reward-related behaviour; and (iii) negative affect including fear learning, stress recovery and the intolerance of uncertainty. To provide further insight into the mechanism of action of antidepressants, the efficacy of selected treatments is tested on changes induced by over-activity of these regions. Beyond the direct relevance of the results presented here to psychiatric disorders and their treatment, the thesis aims to emphasise the importance of broader themes associated with the measurement and quantification of emotion in preclinical animal studies. First, a multi-faceted approach is utilised enabling quantification of both the autonomic and behavioural aspects of emotion. In so doing, the experiments maintain relevance to studies which assess these correlates in isolation, both in humans (which typically measure subjective responses and physiology) and in rodents (which frequently assess behaviour in isolation). The assessment of more than one dimension of emotion confers these studies with improved power to detect maladaptive changes. Second, the experiments described were conducted in the marmoset, a new-world primate. The extensive anatomical homology between marmoset and human prefrontal cortex facilitates the forward-translation of functional results. In combination with the appropriate assays, this renders marmosets as an invaluable species to study the causal contributions of vmPFC subregions to symptoms of psychiatric disorders. I believe that the results of these experiments provide important insights into the causal role primate vmPFC has in relation to the behavioural and physiological aspects of psychiatric symptomatology. Most importantly, I hope that they serve as the foundation for future work to further elucidate the neuropathological processes underlying mental disorders.
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Baker, Stephanie. "Modeling Depression in the Rat: The Development and Usefulness of a Female-centric Approach." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20211.
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Women are twice as likely to suffer from depression as men, yet stress and depression research has relied primarily on the responses of males. Early life stress is hypothesized to influence the development of vulnerability to depression while adult stress exposure can act as a trigger in those predisposed. This relationship is mediated by other environmental factors. Maternal care and the social environment appear to be particularly important for mammals. The purpose of this thesis was twofold: to develop an animal model of depression for use in female rats based on the chronic mild stress (CMS) model previously validated for use in male rodents, and to apply this model in female offspring of mothers exposed to physical restraint in the second half of gestation representing an early life insult. Results indicate that a modified CMS model was able to alter hedonic and physiological responses not present in the original model. Housing condition interacted with CMS in that effects were evident only in singly housed rats. While gestational stress (GS) altered maternal weight and behavioural profiles related to offspring care and anxiety, little to no behavioural effects were noted in juvenile or adult offspring. Applying the modified CMS model to adult female offspring resulted in an anhedonic-like response that recovered rapidly prior to the third week of CMS. Weight in GS female rats was attenuated throughout life beginning post weaning. When taken together, these results demonstrate that stress-based models, previously established in males, must be altered to accommodate the hormonally intact female rat in two ways: first, to eliminate extraneous variables that may interfere with the estrous cycle and mask possible stress effects, and secondly, to consider the appropriateness of individual stressors to induce a stress response in females. While a general lack of effect was noted in response to CMS, this was interpreted as a strong influence of housing and supportive early life experiences in protecting the female rat from the establishment of stress effects related to depression and anxiety. The housing practices employed here may be considered a model of stress-resilience and represents an encouraging avenue of future research.
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Coleman, Joshua B., Wesley Drew Gill, Allee C. Maxwell, and Russell W. Brown. "Analysis of a Poly(ADP-ribose) Polymerase (PARP) Inhibitor in a Treatment-resistant Depression Model in the Rat." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/asrf/2020/presentations/53.
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Over 16 million people in the US suffer from major depressive disorder (MDD) each year. Approximately 1/3rd of MDD patients (~5 million) obtain only partial remission or no benefit after trials with multiple drugs or drug combinations. Recently, Ordway and colleagues have reportedelevated levels of DNA oxidation and upregulated gene expression of the base excision repair enzyme poly(ADP-ribose) polymerase-1 (PARP1) in postmortem brain from donors who had MDD at the time of death, as compared to age-matched psychiatrically normal control donors. This study was designed to test whether an inhibitor of PARP, 3-aminobenzamide (3-AB), may be effective to alleviate depressive-like behaviors in a rodent model of treatment-resistant depression. Male rats were ip administered lipopolysaccharide (LPS;100ug/kg) daily for 28 days, and administered a chronic unpredictable stressor on each day. All rats were also administered saline, 3-AB (40 mg/kg), or the serotonin-reuptake inhibitor (SSRI) fluoxetine (trade name: Prozac; 10 mg/kg) on each day, approximately 30 min after LPS treatment. During the 28 day period of LPS treatment, animals were behaviorally tested 5 times on sucrose preference (a test of anhedonia). At the end of the 28 day period, rats were behaviorally tested on a test of acute stress, the Porsolt swim test. Results revealed that 3-AB alleviated anhedonia and the response to acute stress in the Porsolt swim test superior to the fluoxetine group, demonstrating the utility of a PARP inhibitor to alleviate depressive-like behavior in this model. In addition, fluoxetine produced a loss of weight which recovered over days, but not to control levels, and 3-AB did not produce this effect. This study shows that PARP inhibitors may be effective in treatment-resistant depression.
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FRUMENTO, GIULIA. "Acute stress induces short- and long-lasting modifications of glutamate transmission in the prefrontal cortex at pre- and peri-synaptic compartments." Doctoral thesis, Università degli studi di Genova, 2022. http://hdl.handle.net/11567/1066298.
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Physiological stress promotes adaptive plasticity, but the mechanisms responsible for maladaptation in the presence of an excessive or dysregulated response still remain unknown. Exposure to an acute inescapable foot shock (FS) stress protocol can induce both rapid and sustained changes in synaptic function and neuroarchitecture, suggesting that the effects of a single stressful event are far from being simply acute. Evaluating short- and long-term modifications triggered by acute stress could be a useful tool to dissect adaptive and maladaptive components underlying stress reaction.
On this basis, the aim of the present thesis was to study some early and delayed alterations caused by acute FS stress in neuronal presynaptic (synaptosomes) and astroglia peri-synaptic (gliosomes) compartments purified from prefrontal cortex (PFC) in vulnerable (VUL) and resilient (RES) rats.
We first applied the sucrose test paradigm, to identify RES or VUL rats at different time points after FS stress, thus showing that the anhedonic behaviour started 6h after FS stress and lasted at least for 48h.
FS stress was characterized by an immediate and transient rise of corticosterone levels in both VUL and RES rats respect to controls. 24h after FS stress, when no augmentation of corticosterone level was still detectable, the depolarization-evoked glutamate release was more pronounced in PFC gliosomes of VUL, but not of RES rats. No release changes were found immediately, 6h and 48h after FS stress. No modifications were detected also in basal glutamate release in PFC gliosomes of both VUL and RES rats at each time point investigated.
When focusing on PFC synaptosomes, we observed that the depolarization-evoked glutamate release was significantly increased in both VUL and RES rats respect to controls 24h after FS stress, while the basal glutamate release was increased in VUL animals only.
Studying the molecular mechanisms underlying these functional alterations, we demonstrated that the excessive depolarization-evoked glutamate release measured 24h after FS-stress in VUL PFC gliosomes was mediated by glutamate transporters operating in the reverse mode.
We also found that synapsin I expression did not change in synaptic membranes purified from PFC synaptosomes, while synapsin I phosphorylation in Ser9 was significantly increased in both RES and VUL rats, thus paralleling the increased glutamate release in PFC synaptosomes.
Moreover, mineral corticoid receptors expression was significantly increased in RES rat PFC nuclear fraction whereas that of glucocorticoid receptors was increased in VUL rats.
The present data suggest that acute FS stress induces adaptive/maladaptive stress responses at the synapse level, affecting the neuronal presynaptic counterpart and the surrounding astroglia cells with the alteration of specific molecular mechanisms that might represent new potential pharmacological targets for future therapeutic interventions.
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Imbert, Laetitia. "Déficits du traitement émotionnel dans l’épisode dépressif caractérisé." Electronic Thesis or Diss., Lyon 1, 2024. http://www.theses.fr/2024LYO10260.
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Le trouble dépressif est caractérisé par l’altération du traitement émotionnel, centrée autour de deux concepts principaux : un affect négatif soutenu et une perte de plaisir, appelée anhédonie. Ces altérations jouent un rôle central tant dans le développement que dans le maintien des épisodes dépressifs. Ainsi, l’objectif de ce travail est d’approfondir la compréhension de ces déficits et de proposer un protocole thérapeutique innovant pour mieux les prendre en charge. En utilisant différents outils (tests comportementaux, IRMf, tDCS), nous avons d’abord pu mettre en évidence que le biais attentionnel émotionnel constitue un marqueur de la sévérité de la dépression, soulignant son importance clinique. Nous avons ensuite confirmé le rôle central du dlPFC dans le traitement émotionnel en montrant que 1- sa connectivité fonctionnelle avec des structures sous-corticales (amygdale et noyau accumbens) est liée aux biais attentionnels émotionnels, et 2 – son activation par tDCS améliore les performances à une tâche de traitement émotionnel. Sur la base de ces résultats, nous exposons dans une dernière partie les fondements théoriques à l’utilisation de la combinaison des stimulations cérébrales (rTMS) et sensorielles pour diminuer les déficits du traitement émotionnel dans la dépression, et présentons les résultats préliminaires d’un tel protocol. Ces travaux reproduisent et prolongent des résultats antérieurs, soulignant le rôle clé du dlPFC dans le traitement émotionnel, le positionnant ainsi comme une cible thérapeutique privilégiée dans le traitement de la dépression. Ce manuscrit contribue à l'élaboration de nouveaux outils thérapeutiques, capables de répondre aux défis cliniques posés par cette pathologie complexeDepressive disorder is characterized by impaired emotional processing, centered around two main concepts: sustained negative affect and loss of pleasure, known as anhedonia. These alterations play a central role in both the development and maintenance of depressive episodes. Thus, the objective of this work is to deepen the understanding of these deficits and propose an innovative therapeutic protocol to better address them.Using various tools (behavioral tests, fMRI, tDCS), we first demonstrated that emotional attentional bias is a marker of depression severity, underscoring its clinical significance. We then confirmed the central role of the dlPFC in emotional processing by showing that 1) its functional connectivity with subcortical structures (amygdala and nucleus accumbens) is associated with emotional attentional biases, and 2) its activation by tDCS improves performance in an emotional processing task. Based on these findings, we outline in the final section the theoretical basis for using a combination of brain (rTMS) and sensory stimulations to reduce emotional processing deficits in depression, and present preliminary results from such a protocol. This work reproduces and extends previous findings, highlighting the key role of the dlPFC in emotional processing, positioning it as an ideal therapeutic target in treatment of depression. This manuscript contributes to the development of new therapeutic tools capable of addressing the clinical challenges posed by this complex pathology
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Alves, Aron de Miranda Henriques. "Investigando fen?tipos comportamentais e eletrofisiol?gicos associados ao estresse social." PROGRAMA DE P?S-GRADUA??O EM NEUROCI?NCIAS, 2015. https://repositorio.ufrn.br/jspui/handle/123456789/21620.
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Os objetivos desta tese foram os de investigar padr?es comportamentais e eletrofisiol?gicos associados ? resili?ncia e suscetibilidade ao estresse social induzido em camundongos. Para isso, utilizamos um protocolo de indu??o de estresse cr?nico cont?nuo a partir de derrotas sociais baseado no paradigma residente-intruso. Os resultados da tese s?o apresentados em dois estudos. No primeiro estudo, camundongos C57BL/6J submetidos a epis?dios repetidos de derrota social apresentaram motiva??o tardia para interagir com um camundongo desconhecido em sess?es prolongadas (10 min) do teste de intera??o social. Utilizando uma abordagem etol?gica associada ? an?lise computacional de v?deos foi poss?vel rastrear precisamente a posi??o dos camundongos durante a realiza??o de comportamentos de investiga??o social. Analisamos ainda a express?o detalhada de comportamentos defensivos, tais como investiga??o em postura estendida e fugas, ambos associados ao comportamento de investiga??o social. A partir dessas an?lises demonstramos que a realiza??o do comportamento de investiga??o social em postura estendida era significativamente maior para o grupo derrotado comparado ao grupo controle. Ainda, um subgrupo de camundongos derrotados apresentou investiga??o social em postura estendida de forma persistente e sem habitua??o. Utilizando uma medida da dist?ncia de investiga??o durante as investiga??es sociais calculamos um ?ndice de aproxima??o (IA) para cada animal e separamos um subgrupo apresentando fen?tipo relacionado ? ansiedade. A incid?ncia de fugas tamb?m foi maior no grupo derrotado em compara??o com os controles. A persist?ncia na ocorr?ncia desse comportamento foi observada em um subgrupo de camundongos submetidos ?s derrotas sociais. Calculamos ent?o um ?ndice de fugas (IF) que se correlacionou inversamente com a prefer?ncia por sacarose, sendo ?til para identificar animais aned?nicos. No segundo estudo, foram combinados an?lise etol?gica e registros eletrofisiol?gicos com tetrodos na ?rea tegmentar ventral de camundongos submetidos ? derrotas sociais. Utilizando crit?rios eletrofisiol?gicos e farmacol?gicos classificamos unidades na ?rea tegmentar ventral como supostos neur?nios dopamin?rgicos e n?o-dopamin?rgicos. Durante o comportamento de investiga??o social foi observado que a modula??o da taxa de disparo dessas subpopula??es neuronais distintas ocorreu de maneira oposta em animais suscet?veis e resilientes ao estresse social. Em suma, propomos que sess?es prolongadas associadas ? an?lise etol?gica detalhada durante os testes de intera??o social podem prover informa??o para classifica??o de camundongos em resilientes e suscept?veis ap?s repetidas derrotas sociais. Ainda, a express?o do fen?tipo suscet?vel parece estar associada ao comprometimento do sistema dopamin?rgico mesol?mbico na atribui??o de valor de incentivo ?s intera??es sociais normalmente associadas ao aumento da atividade neuronal mesol?mbica.
The aims of this thesis were to investigate behavioral and electrophysiological patterns associated to resilience and susceptibility to social stress in mice. For this, we used a chronic social defeat stress protocol based on the resident-intruder paradigm. The results are presented here in two studies. In the first study, C57BL/6J mice submitted to repeated social defeat episodes showed delayed motivation to interact with an unfamiliar conspecific in long duration (10 min) sessions of the social interaction test. By using an ethological approach combined with computational video analysis, it was possible to track precisely the mouse position during social investigation behavior performance. With that approach, it was analyzed the detailed expression of defensive behaviors, such as stretched attended postures and flights, both associated to social investigation behaviors. From these analyzes, it was demonstrated that social investigation behaviors based on stretched attend postures were significantly higher in defeated mice in comparison to controls. Still, a subpopulation of defeated mice showed persistently and non-habituating stretched attend postures during social investigation. By using a measure based on the investigation distance during social investigations, it was possible to compute an approach index (AI) to each animal and separate a subpopulation showing an anxiety-related phenotype. The flight incidence was also increased in defeated group as compared with controls. The persistent occurrence of this behavior was observed in a subpopulation of defeated mice. We calculated a flight index (FI) that inversely correlated with sucrose preference, showing to be useful to identify anhedonic animals. In the second study, we combined ethological approach and electrophysiological recordings in the ventral tegmental area of mice submitted to chronic social defeat stress. By using electrophysiological and pharmacological criteria, single-units recorded from the ventral tegmental area were classified as putative dopaminergic and non-dopaminergic neurons. During the social investigation behavior it was observed that firing rate modulations of distinct neuronal subpopulations occurred in opposite manner in social defeat susceptible and resilient mice. In summary, this work proposes that longer sessions of the social interaction test associated to ethological approach can provide information for the behavioral classifications of resilient and susceptible mice after social defeat stress. Furthermore, the expression of susceptible phenotype could be related to the midbrain dopaminergic system impairment in the incentive value assignment to social interactions normally associated with increased mesolimbic neuronal activity.
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Yazbek, Hanan. "Nécessité d'une approche multidimensionnelle de l'apathie dans la schizophrénie : études transversales et longitudinales de l'apathie en lien avec l'anhédonie et le système motivationnel." Thesis, Montpellier 3, 2013. http://www.theses.fr/2013MON30104.
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La schizophrénie (SZ), maladie psychiatrique invalidante, est caractérisée par des symptômes positifs, négatifs, cognitifs, désorganisés, affectifs et moteurs. De par l’absence de résultats positifs dans la prise en charge des symptômes négatifs, nous avons décidé de nous intéresser à l’apathie dans la SZ. Elle se définit par une baisse des comportements dirigés vers un but ayant une origine cognitive, émotionnelle ou comportementale. Notre objectif est d’apporter un éclaircissement sur le concept d’apathie en s’intéressant aux liens entre apathie, anhédonie et BIS/BAS. Le protocole 1 porte sur la validation de la Lille Apathy Rating Scale (LARS), outil multidimensionnel de l’apathie validée dans la maladie de Parkinson, dans la SZ, auprès de 112 patients. Le protocole 2 (étude transversale) s’intéresse aux liens entre apathie, plaisir consommé, anticipatoire, sociale et BIS/BAS, auprès de 112 patients. Enfin, le protocole 3 (étude longitudinale d’un an) porte sur l’évolution de l’apathie et explore les déterminants émotionnels et comportementaux qui pourraient la prédire, auprès de 61 patients. Nos résultats ont mis en évidence une LARS à quatre facteurs avec de bonnes qualités psychométriques dans la SZ. Le facteur 1 est associé au BAS, à l’anhédonie sociale et anticipatoire. Le facteur 2 corrèle avec le BIS et l’anhédonie sociale. Trente-six pourcent des patients ont une apathie trait. Enfin, seul leplaisir anticipatoire prédit le facteur 4. L’apathie nécessite donc pour sa compréhension une approche multidimensionnelle. L’anhédonie et le BIS/BAS ne peuvent expliquer à eux seuls l’apathie émotionnelle et comportementale. D’autres pistes méritent donc d’être exploréesSchizophrenia (SZ) is a chronic psychiatric disease characterized by positive, negative, cognitive, disorganized, emotional and motor symptoms. The lack of positive results in the treatment of negative symptoms led us to be interested in apathy. Apathy is defined as a multidimensional psychopathological state (cognitive, emotional, and behavioral) manifesting as a reduction of voluntary behaviors directed toward one goal. Our aim is to provide a clarification of the concept of apathy by focusing on the relationship between apathy, anhedonia and BIS/BAS. The first study deals with the validation of the Lille Apathy Rating Scale (LARS), which is a multidimensional tool of apathy validated in Parkinson’s disease, in 112 SZ patients. The second study (cross-sectional study) focuses on the link between apathy, consummatory and anticipatory pleasure, social pleasure and BIS/BAS, in 112 SZ patients. Finally, the third study (one year longitudinal study) deals with the evolution of apathy and explores the emotional and behavioral derminants that could predict it. Ours results have shown that the LARS is structured in four factors and has good psychometric properties in SZ. The factor 1 is associated to the BAS and the social and anticipatory anhedonia. The factor 2 is linked to the BIS and the social anhedonia. Thirty-six percent of the patients have an apathy trait. Finally, only anticipatory pleasure predicts the factor 4. Therefore, apathy requires for its understanding a multidimensional approach.Anhedonia and the BIS/BAS cannot by themselves explain the emotional and the behavioral apathy. Consequently, others lines of research need to be explored
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Christ, Nicole M. "Psychophysiological Correlates of Novel, Negative Emotional Stimuli in Trauma-Exposed Participants with PTSD Symptoms." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1534160952853362.
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Macedo, Isabel Cristina de. "Modelo de obesidade e estresse crônico em ratos wistar : avaliação do comportamento alimentar, de anedonia e de níveis centrais de BDNF." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/122348.
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A obesidade tornou-se um dos mais graves problemas de saúde pública em todo o mundo, e o aumento na ingestão de alimentos hipercalóricos tem contribuído significativamente para o desenvolvimento desta doença. Este distúrbio metabólico pode ocasionar diversas outras comorbidades. Por outro lado, o estresse crônico, seja associado à obesidade ou não, leva a diferentes alterações neuroendócrinas e psicológicas. Estruturas cerebrais, especialmente o hipotálamo, estão envolvidas no controle do apetite. Atualmente, o hipocampo também tem sido associado ao controle do consumo alimentar. Neste contexto, o fator neurotrófico derivado do cérebro (BDNF) que é amplamente expresso em todas as regiões do cérebro e desempenha um papel importante na sobrevivência neuronal e na neuroplasticidade tem sido associado à regulação da homeostase energética e da ingestão alimentar. Assim, o objetivo desta tese foi investigar os efeitos da obesidade induzida por dieta hipercalórica sobre parâmetros neuroquímicos e comportamentais com base em dois protocolos experimentais. No primeiro protocolo experimental, 30 ratos Wistar adultos foram divididos igualmente em 2 grupos de acordo com modelo de dieta: grupo controle, que recebeu ração padrão, e grupo dieta de cafeteria, alimentado com dieta de cafeteria. O objetivo do protocolo experimental foi investigar os efeitos da obesidade induzida por dieta hipercalórica em parâmetros neuroquímicos e comportamentais. Foram avaliados ganho de peso, comportamento hiperfágico, comportamento do tipo ansioso e atividade locomotora no labirinto em cruz elevado e no aparato de campo aberto, respectivamente. Também foram avaliados os níveis de BDNF e a susceptibilidade ao dano induzido por H2O2 com liberação de lactato desidrogenase (LDH) em tecido hipocampal. Foi possível observar que a exposição à dieta de cafetaria durante 6 semanas resultou em obesidade, hiperfagia e aumento na atividade locomotora. Animais obesos mostraram diminuição dos níveis de BDNF e aumento da susceptibilidade a danos celulares no hipocampo. As alterações comportamentais em resposta à exposição à dieta de cafeteria podem ser relacionadas com os seus efeitos neuroquímicos no cérebro, e a deficiência na regulação do apetite (hiperfagia) que pode estar associada à perda de integridade do hipocampo. No segundo protocolo experimental, 32 ratos Wistar adultos foram divididos igualmente em 4 grupos de acordo com a dieta hipercalórica (modelo de dieta de cafeteria) e modelo de estresse crônico por restrição: grupo controle que recebeu dieta padrão; grupo estresse que foi exposto ao modelo de estresse crônico por restrição; grupo dieta hipercalórica, que recebeu a dieta hipercalórica e grupo estresse + dieta hipercalórica, que foi exposto ao modelo de estresse crônico por restrição e recebeu dieta hipercalórica. O objetivo foi avaliar o efeito da obesidade associada com o estresse crônico sobre os níveis centrais de BDNF. O peso do animal e a ingestão calórica foram empregados como parâmetros de obesidade enquanto o peso relativo da glândula adrenal foi empregado como parâmetro de estresse. Demonstrou-se que o estresse crônico por restrição, por 12 semanas, aumenta o peso da glândula adrenal, diminui os níveis de BDNF no hipocampo e está associado com decréscimo na ingestão de sacarose, caracterizando anedonia. O aumento na glândula adrenal demonstra a intensa estimulação desta estrutura. A diminuição no consumo de sacarose associada à diminuição do BDNF hipocampal pode sugerir um comportamento depressivo. Por outro lado, os ratos que receberam a dieta hipercalórica tiveram aumento na ingestão de calorias e tornaram-se obesos, resultado que foi associado a uma diminuição dos níveis de BDNF hipotálamo.Obesity has become one of the most serious worldwide public health problems and increment on hypercaloric food intake has contributed significantly to the development this disease. This metabolic disorder can lead to various other comorbidities. On other hand chronic stress, whether associated with obesity or not, leads to different neuroendocrine and psychological changes. Brain structures, especially hypothalamus, are involved in food control. Currently the hippocampus also has been associated with energy intake. In this context, brain-derived neurotrophic factor (BDNF) that is widely expressed in all brain regions and plays an important role in neural survival and neuroplasticity has been implicated in the regulation of energy homeostasis and food intake. Thus, the aim of this thesis was to investigate the effects of hypercaloric diet-induced obesity associated or not to chronic stress by restriction on neurochemical and behavioral parameters based on two experimental protocols. In first experimental protocol 30 Wistar adults rats were equally divided on two groups according to diet model: control group that received standard rat chow and cafeteria diet group that received cafeteria diet model. The aim of the experiment protocol was to investigate the effects of hypercaloric diet-induced obesity on neurochemical and behavioral parameters. Were evaluated the weight gain, hiperfagic behavior, and the anxiety-like behavior and locomotor activity on Plus Maze and the Open Field tests, respectively. Were evaluated also the BDNF levels and susceptibility to H2O2-induced oxidative damage with LDH release of hippocampal tissue. In this experimental protocol was possible to observe that exposure to the cafeteria diet for six weeks resulted in obesity, hyperphagia and increased on locomotor activity. Obese animals showed decreased BDNF levels and increased susceptibility to cellular damage in the hippocampus. The behavioral consequences of exposure to the cafeteria diet may be related to its biochemical effects on the brain and impairments food intake regulation (hyperphagia) might be associated to the loss of hippocampal integrity. In second experimental protocol 32 Wistar adults rats were divided on four groups according to hypercaloric diet (cafeteria diet model) and chronic restraint stress model: (C) control total group that received standard rat chow; (S) stress group that was exposure to chronic restraint stress model and received standard rat chow; (HD) group that received hypercaloric diet and (SHD) stress group that was exposure to chronic restraint stress model and received hypercaloric diet. The aims of experimental protocol were to evaluate the effect of obesity associated with chronic stress on the BDNF central levels of rats. Obesity was controlled by analyzing the animals’ caloric intake and changes in body weight. As a stress parameter, was analyzed the relative adrenal gland weight. This experimental protocol demonstrated that chronic restraint stress for 12 weeks increased the weight of the adrenal gland, decrease BDNF levels in the hippocampus and is associated with a decrease in sucrose intake, characterized anhedonia. The increase in the adrenal gland demonstrates the intense stimulation of this structure. The decrease in the consumption of sucrose associated with decreased hippocampal BDNF may suggest a depressive behavior. On the other hand, mice that received hypercaloric diet had an increased caloric intake and became obese, which was associated with a decrease in BDNF levels hypothalamus.
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Krüger, Andreas. "Alexithymie und Anhedonie bei psychosomatischen Patienten eine klinische Untersuchung /." [S.l.] : [s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=968640508.
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Stauffer, Kathryn Elizabeth. "Physiological Responding in Anhedonic and Perceptually Aberrant College Students." W&M ScholarWorks, 1991. https://scholarworks.wm.edu/etd/1539625698.
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Benitez, Andreana. "Executive Functioning Abilities are Differentially Associated with Anhedonic Depression and Anxious Arousal." Kent State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=kent1276455545.
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Desmidt, Thomas. "Physiologie cardiaque et cérébrovasculaire dans la dépression." Thesis, Tours, 2012. http://www.theses.fr/2012TOUR3320.
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Dépression et maladies cardiovasculaires sont liées mais la physiopathologie de cette association est mal connue. Les mécanismes de la variabilité de la fréquence cardiaque (VFC) et de la dysfonction endothéliale (DE) pourraient rendre compte de cette association mais leur implication demeure controversée et seuls certains symptômes de la dépression, l’anhédonie et l’hyporéactivité émotionnelle (HE), semblent leur être associés. En outre, certains obstacles méthodologiques ont, jusqu’à présent, limité l’étude de la réactivité cardiaque et cérébrovasculaire dans l’anhédonie et l’HE. Dans ce travail, nous établissons par deux protocoles expérimentaux distincts 1) qu’une nouvelle technique d'échographie cérébrale (Tissue Pulsatility Imaging - TPI) permet de mettre en évidence des modifications de la réactivité cérébrovasculaire dans la dépression et 2) qu’il est possible d’associer la VFC et l’anticipation émotionnelle, processus clef dans l’HE. Nos résultats suggèrent que l’anhédonie et l’HE de la dépression peuvent être caractérisées par un trouble de l’anticipation émotionnelle, lui-même associé à une VFC diminuée et une DE cérébraleDepression and cardiovascular diseases are related but the physiopathology of this association is unclear. Heart rate variability (HRV) and endothelial dysfunction (ED) could account for this association but their involvement remains controversial and only some symptoms of depression, anhedonia and emotional hyporeactivity (EH), seem to be involved. In addition, some methodological obstacles have so far limited the assessment of cardiac and cerebrovascular reactivity in anhedonia and EH. In this work, we establish using two distinct protocols 1) that cerebrovascular changes in depression can be assessed using a new ultrasound technique (Tissue Pulsatility Imaging - TPI) and 2) that HRV and emotional anticipation, as a key process in EH, are associated. Our results suggest that anhedonia and EH in depression can be characterized by a blunted emotional anticipation which is associated with a decreased HRV and a cerebral ED
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PILUDU, MARIA ANTONIETTA. "Characterization of the Roman lines/strains of rats as a genetic model of psychiatric disorders: a behavioral and brain dialysis study." Doctoral thesis, Università degli Studi di Cagliari, 2016. http://hdl.handle.net/11584/266712.
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State of the art Depressive disorders are fairly prevalent in the general population, with a higher rate in women compared to men, are disabling, since they can significantly impair psychosocial functioning, and are typically associated with high mortality due mainly to the high rate of suicides but also to the negative impact that depression has on the course of co-occurring illnesses. In addition, pharmacological and psychological antidepressant therapies in use have a limited efficacy and/or are associated with side effects that reduce the compliance in many patients. Although the etiology and pathogenesis of depression are poorly understood, it is most likely that the combination of genetics, early life adverse events, and ongoing stress may ultimately determine the individual vulnerability to stress-related disorders, such as depression. Therefore, the development and characterization of animal models of vulnerability and resistance to the effects of stress, including early life stress, is a major challenge for depression research.
One such model is represented by the Roman high- (RHA) and low-avoidance (RLA) lines/strains of rats, which are psychogenetically selected for, respectively, rapid versus extremely poor acquisition of active avoidance in a shuttle box. A large body of evidence indicates that a major reason for their divergent performance in this test is their different reactivity to stressful stimuli, that is, their coping style. Thus, when exposed to aversive stimuli, RLA rats display a reactive coping strategy, associated with a strong activation of the HPA axis; moreover, they display robust depressive-like behaviors in the forced swim test (FST) that are normalized by the subacute administration of antidepressants. In contrast, compared with their RLA counterparts, RHA rats display a proactive coping strategy in the face of aversive conditions, associated with higher baseline levels of impulsivity, a more robust sensation/novelty seeking profile, a marked preference for, and intake of, natural and drug rewards along with a greater responsiveness of the mesolimbic dopaminergic system.Aims The behavioral and neurochemical traits that distinguish the two lines/strains suggest that RLA rats may represent a model of vulnerability to stress-induced depression, whereas RHA rats may model resistance to stress-induced depression-like behaviour.
To test this hypothesis, in the first study we evaluated the performance of RLA and RHA rats in the FST in response to chronic antidepressant treatments, since clinical evidence indicates that several weeks of treatment with antidepressant drugs are required to achieve an adequate therapeutic response.
Furthermore, one of the cardinal symptoms of depression observed in many patients is anhedonia, which is defined as the loss of interest in once enjoyable activities, including sexual activity. Accordingly, depressive episodes are frequently associated with sexual dysfunctions. In consideration of this clinical evidence, and given the well-established role of dopamine in sexual behavior, the second study was aimed at characterizing the sexual behavior of RHA and RLA rats and its correlation with the functional state of their mesolimbic dopaminergic system.
In keeping with the long-term consequences on mental health elicited by early-life adverse events, it has been observed that post weaning social isolation in rodents may lead to a later increment in the prevalence of anxiety/fear related behaviors. Thus, in the third study we evaluated the impact of post weaning isolation on the anxiety-related behaviors of inbred RHA and RLA rats in the Elevated Zero Maze, and in motility cages used to asssess locomotor activity in a new environment.
Results In study I we demonstrated that chronic treatments with low doses of antidepressants, that were ineffective when given subacutely, were able to decrease immobility and also to increase climbing (desipramine) or swimming (fluoxetine) in RLA rats. Conversely, neither subacute nor chronic antidepressant treatments affected the behavior of RHA rats in the FST.
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In addition, the results of study II showed that, compared with their RLA counterparts, RHA rats displayed higher levels of sexual motivation and a better copulatory performance, associated with a greater release of DA in the AcbSh. These line-related differences were attenuated but not abolished by sexual experience. Moreover, RLA rats were more responsive than their RHA counterparts to both, the facilitatory effect of apomorphine and the inhibitory effect of haloperidol on sexual behavior.
Finally, in study III we found that the isolation-rearing procedure significantly increased the level of anxiety of RHA-I rats in the EZM, as reflected by a smaller number of entries and a shorter time spent in the open space, associated with decreased head dipping, increased latency to enter in the open space, and reduced novelty-induced locomotor activation, whereas it failed to produce significant changes in the behavior of RLA-I rats.
Conclusions The results of these studies show that the Roman lines/strains of rats may represent a valid experimental approach to investigate the neural substrates and molecular mechanisms involved in the individual vulnerability and resistance to stress-induced depression, with the aim of identifying both, potential biomarkers for an early diagnosis of depression and potential molecular targets for novel antidepressant treatments. Moreover, the Roman lines/strains may be used to study the neurophysiology of the appetitive and consummatory aspects of sexual behaviour, in order to better understand the mechanisms underlying the psychological and pathological causes of sexual dysfunctions. Finally, the Roman rats may provide a useful model to identify the mechanisms whereby early-life adverse events interact with the genetic make up to induce psychiatric disorders in adulthood.
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Rouibi, Khalil Adnane. "Dépendance aux drogues opiacées : focus sur le système corticotropin-releasing factor." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14434/document.
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La prise illicite de drogues opiacées est un problème majeur de santé publique dans le monde. L’apparition du syndrome de sevrage aux opiacés (SAO) suite à l’arrêt de prise d’opiacés est considérée comme élément clef dans la vulnérabilité associée à la rechute de prise d’opiacés. En effet le syndrome de SAO est caractérisé par des altérations comportementales et neurobiologiques en réponse au stress qui sont déterminantes dans le phénomène de dépendance aux opiacés. Le système corticotropin-releasing factor (CRF) est un coordinateur central des circuits de réponse au stress par l’intermédiaire de ses deux récepteurs le: CRF1 et CRF2. L’objectif de cette thèse est de déterminer le rôle du récepteur CRF2 dans l’apparition des états affectifs négatifs et des désordres motivationnels impliqués dans la rechute de la consommation de drogues opioïdes lors du SAO.Nous avons démontré par une série d’expériences conduite chez des souris invalidées au récepteur CRF2 (CRF2-/-), que la délétion génétique du récepteur CRF2-/- éliminait les états dysphoriques ainsi que les altérations moléculaires induites par le SAO sans détériorer les réponses neuroendocriniennes qui sont primordiales lors des adaptations aux stress associées au sevrage. De surcroît, nous avons trouvé que les souris CRF2-/- entrainées dans une procédure de tâche opérante dirigée vers l’obtention d’une nourriture palatable, montraient une diminution des troubles motivationnels induits par le SAO. Plusieurs rapports montrent que chez l’Homme, les évènements stressants apparaissant lors d’une période de sevrage provoquent une rechute de la consommation d’alcool ou de drogues. Nous avons développé un modèle murin qui montrait un rétablissement de recherche de nourriture palatable suite à une procédure de stress appliquée pendant une période de SAO. Par ailleurs, nous avons observé un dimorphisme sexuel du rôle du récepteur CRF2 dans le rétablissement de recherche de nourriture palatable, suite au stress, longtemps après un SAO.Les résultats de ce travail de thèse nous permettent de mettre en avant le récepteur CRF2 comme possible cible thérapeutique dans le traitement de la dépendance aux opiacésOpiate illicit use represents one of the most severe sanitary problems throughout the world. Among humans, the emergence of the opiate withdrawal (OW) syndrome after cessation of opiate intake is considered as one of the key motivational elements that lead to the vulnerability to opiates relapse. Therefore, the OW is characterized by a various alterations of the behavioral and neurobiological homeostasis responses to stress which are determinants in opiate dependence. The Corticotropin-releasing factor (CRF) system is the major coordinator of stress-responsive circuitry. Through its two receptors CRF1 and CRF2, the CRF system has recently emerged as major contributor in the development of components of the OW syndrome. The aim of this thesis is to determine the role of CRF2 receptor in the negative affective states and motivational disorders implicated in opiate relapse during OW.Behavioral and biological experiments were conducted in CRF2 receptor-deficient mice (CRF2-/-). We reported that genetic deletion of the CRF2 receptor eliminates dysphoria and molecular alterations elicited by OW without impairing brain, neuroendocrine and autonomic stress-coping responses to withdrawal. Using behavioral approaches of operant responding to highly palatable food (HPF) we found that CRF2-/- reduces motivational disorders induced by intermittent morphine injections and withdrawal. Finally, we described a mouse model of stress-induced food reinstatement seeking behavior during prolonged OW. Furthermore, we reported a gender dimorphism in the role of the CRF2 receptor in the stress-induced reinstatement of HPF seeking behavior long-lasing after opiate treatment.These findings underscore the importance of CRF2 receptor as possible effective treatment of the critical problem of opiate dependence
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Prévot, Thomas. "Pathogénicité du stress chronique chez l'adulte dans un modèle murin : impact à long terme et rôle de la somatostatine." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0321/document.
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Le stress a une fonction adaptative mais son influence délétère sur la santé physique,cognitive et mentale lorsqu’il se présente de façon excessive et/ou chronique est aujourd’huireconnue. De très nombreux travaux ont démontré que le jeune enfant, l’adolescent et le sujetâgé y sont particulièrement vulnérables. L’objectif de cette thèse a été de déterminer s’ilexiste une sensibilité au stress chronique chez l’adulte selon l’âge au moment de l’exposition.Le modèle de stress chronique léger et imprédictible mis au point chez la souris a été utilisé.Les impacts à court et long-terme (sujet âgé), ont été déterminés en analysant les troublessomatiques, hédoniques, anxieux, dépressifs et cognitifs, caractéristiques du syndrome destress. Contrairement à l’idée selon laquelle l’adulte serait plus résistant et plus résilient auxperturbations induites par le stress, les résultats de cette thèse démontrent qu’une période destress à l’âge adulte produit des effets délétères drastiques non seulement immédiats maiségalement à long terme. Toutefois, l’adulte d’âge moyen serait plus résistant et plus résilientrelativement aux adultes jeunes ou d’âge avancé qui présentent une symptomatologie plusmarquée. La sévérité des symptômes anxieux initialement générés par le stress est corrélée àla fois avec la persistance des troubles et la modification des marques de répression géniquedans l’hippocampe indiquant la présence d’une signature épigénétique de l’épisode de stress àlong terme. Des études récentes ont suggéré l’implication de la somatostatine centrale dans lesrégulations émotionnelles et relient la vulnérabilité au stress chronique des neuronessomatostatinergiques avec le développement de troubles anxio-dépressifs. Les résultats decette thèse ont permis d’identifier l’inhibition à la fois de l’axe HPA et des comportementsanxio-dépressifs par les récepteurs sst2 et sst4 de l’hippocampe. Les profils comportementauxinduits par l’utilisation d’agonistes sélectifs ou par la délétion de ces deux récepteurssuggèrent l’existence de deux voies de régulation interagissant respectivement avec lessystèmes sérotoninergique (voie sst2) et noradrénergique (voie sst4), l’une régulantprincipalement l’état anxieux, l’autre les désordres dépressifs et cognitifs. Ainsi, cette thèseétaye l’importance de la pathogénicité du stress chronique chez l’adulte et l’importance desrégulations neuroendocriniennes et cognitivo-émotionnelles par les récepteurs sst2 et sst4, unespécificité qui doit être prise en considération dans l’utilisation et le développement destraitements somatostatinergiques ciblantStress has an adaptive function but it can have also deleterious effects on physical,cognitive and mental health when its intensity and/or chronicity increase. A large body ofevidence supports the idea that young children, adolescents and aged people are highlysensitive to stress. The aim of this study was to determinate if a critical period of sensitivity tostress may be evidenced during adulthood. The Unpredictable Chronic Mild Stress protocoldeveloped in the mouse was used. Short and long-term impacts of stress were quantified byassessing somatic, hedonic, anxious, depressive and cognitive troubles which arecharacteristic of a stress syndrome. Unlike the view that adults are resistant and resilient tostress, the results presented in this thesis show that a stress period during adulthood inducesimmediate and long-lasting deleterious effects. However, middle-aged adults were moreresistant and more resilient than younger or older subjects which both displayed a more severesymptomatology. The anxiety level initially induced by chronic stress is correlated with thepersistence of troubles and with modifications of gene repression marks in the hippocampus,indicating the presence of an epigenetic signature of the chronic stress episode in the longterm.Recent studies have suggested that central somatostatin is involved in emotionalregulations, linking the vulnerability of somatostatinergic neurons to chronic stress with theinstatement of anxio-depressive disorders. We showed herein that hippocampal sst2 and sst4receptor subtypes mediate the inhibition of HPA axis and improve anxio-depressivebehaviors. Behavioral patterns induced by either selective agonists or deletions of thesereceptors suggest that two regulatory pathways respectively interact with the serotoninergicsystem (sst2) and the noradrenergic system (sst4). In addition, sst2 receptors mainly regulateanxiety whereas sst4 is mainly involved in the regulation of cognitive and depressivedisorders. As a whole, this thesis corroborates the idea that chronic stress has pathogeniceffects even in adulthood and highlights the importance of neuroendocrine and cognitivoemotionalregulations by sst2 and sst4 receptor subtypes, a specificity that has to beconsidered in the use and the development of somatostatin treatments targeting HPAderegulations and stress-related disorders
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Mann, Monica Constance. "Verbal and nonverbal expressions as indicators of social and emotional functioning among social anhedonics." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3594.
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Thesis (M.A.) -- University of Maryland, College Park, 2006.Thesis research directed by: Dept. of Psychology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Praméus, Klas. "Tondövhet i allmänhet : En studie om hur personer som via test anses som tondöva upplever och uppskattar musik." Thesis, Högskolan Dalarna, Ljud- och musikproduktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:du-24563.
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Denna undersökning syftar till att bidra till en ökad förståelse kring hur personer som upplevs vara tondöva uppfattar och upplever musik. Webbenkät med tillhörande test och semistrukturerad forskningsintervju har använts som metod. Den inledande webbenkäten innehöll två olika tester utvecklade av radiologen Jake Mandell på Harvard Medical School i Boston. Den ena testen undersöker testpersonens förmåga att uppfatta olikheter i tonskillnader. Den andra kallas för "Tone Deafness test" och spelar upp två melodier som antingen är identiska eller innehåller vissa tonskillnader, därefter ska testpersonen avgöra om det var samma melodi som spelades eller inte. Efter bedömning av insamlat resultat kallades tre personer till intervju. Analysen av resultatet visade att den sociokulturella uppväxten skiljer sig hos respondenterna, vilket har påverkat deras relation till musik. Svaren från intervjuerna visar också att även om respondenterna inte lyssnar helt till musiken så kopplar de till den emotionellt. Ofta relateras musiken till minnen där de för första gången hörde låten eller när någon person de står nära spelat upp den. En av respondenterna svarade att, trots faktumet att hon inte förstår musik, så kan klassisk orkestral musik ge upphov till tårar.
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Sarramon, Christine. "Vulnérabilité pour les conduites addictives (Recherche de sensations, anhédonie, impulsivité). A partir d'une étude chez 65 patients hospitalisés en psychiatrie." Bordeaux 2, 1997. http://www.theses.fr/1997BOR23049.
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Payet, Jeanne. "Phénoménologie clinique des conduites suicidaires de l'adolescent, à partir d'une étude de 50 patients hospitalisés." Bordeaux 2, 1997. http://www.theses.fr/1997BOR23058.
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Collins, Lindsay M. "Behavioral indicators of schizotype in the biological parents of social anhedonics: a preliminary examination of the familiality of schizotypal signs." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/2581.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2006.Thesis research directed by: Psychology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.