Dissertations / Theses: 'Cognitive correlates'

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Ortiz, Gil Jordi. "The neural correlates of cognitive impairment in schizophrenia / Els correlats neurals del dèficit cognitiu en l’esquizofrènia." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/91283.

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Background: In recent years it has become recognized that schizophrenia is associated with cognitive impairment, which affects particularly executive function and memory. Although cognitive impairment implies brain damage or dysfunction, little is known about the relationship of cognitive impairment in schizophrenia to the structural and functional brain abnormalities that characterize the disorder. Aims and hypothesis: This study aimed to identify structural and/or functional brain abnormalities associated with cognitive impairment in schizophrenia. According to the literature reviewed, the general hypothesis is that the cognitive deficits of schizophrenic patients are reflected in both structural and functional brain changes. Accordingly, we expect that patients with cognitive impairment will have more GM reductions and more dysfunctional patterns of brain activity than patents without such deficits. Method. structural MRI and voxel-based morphometry was carried out in 26 cognitively impaired and 23 cognitively preserved schizophrenia patients, plus 39 matched controls. Nineteen cognitively impaired patients, 18 cognitively preserved patients and 34 controls also underwent fMRI during performance of a working memory task. Some subjects, partly corresponding to the ones participating in the neuroimaging study, were also administered a battery of tests of different cognitive functions. Altogether, 25 participants with schizophrenia and relatively preserved cognitive function, 29 with impaired functions and 22 healthy participants were included in this part of the study. Results: The participants with cognitive impairment in executive functioning and memory also perform worse on visuospatial and language tasks when compared to other patients intact in memory and executive function and controls. These differences are independent of estimated premorbid IQ. No differences were found between the cognitively intact and cognitively impaired groups in lateral ventricular volume or whole brain volume. Voxel-based morphometry also failed to reveal clusters of significant difference in either GM or WM volume between the two patient groups. However, during performance of the n-back task, the cases with schizophrenia and impaired cognitition showed hypoactivation compared to the cognitively intact patients in DLPFC among other brain regions. Conclusions: This study provides evidence that structural brain abnormality in schizophrenia is a function of having the disorder, not the cognitive impairment that accompanies it. In contrast, a substantial part of the task-related functional imaging abnormality appears to reflect cognitive impairment.
MARCO: Los déficits cognitivos son una característica conocida de la esquizofrenia. Sin embargo, poco se sabe sobre su relación con las anormalidades cerebrales tanto estructurales como funcionales que caracterizan dicha enfermedad. OBJETIVOS: Identificar las alteraciones estructurales y/o funcionales asociadas al déficit cognitivo en la esquizofrenia. MÉTODO: Se adquirió imágenes de resonancia magnética funcional (RMf) y morfometría basada en el vóxel (VBM) en 26 participantes que tenían alteraciones cognitivas y 23 que presentaban una cognición relativamente preservada, todos con esquizofrenia, así como en 39 controles apareados. Diecinueve de quienes presentaban déficits cognitivos y 18 de los preservados cognitivamente y 24 controles también ejecutaron una tarea n-back de memoria de trabajo durante la adquisición de imágenes de RMf. RESULTADOS: No se encontró diferencias entre los participantes con cognición preservada y quienes presentaban déficits cognitivos en el volumen de los ventrículos laterales ni tampoco en el volumen cerebral total. La VBM tampoco mostró clústers con diferencias significativas entre ambos grupos en el volumen de sustancia blanca y gris. Sin embargo, durante la realización de la tarea n-back de memoria de trabajo, los participantes con alteración cognitiva presentaron hipoactivación en la corteza prefrontal dorsolateral, entre otras regiones, en relación a quienes mostraban una cognición preservada. CONCLUSIONES: No se encontró evidencia de que los déficits cognitivos de la esquizofrenia sean una función de anormalidades cerebrales estructurales que acompañan a la enfermedad sino que se asociarían con un funcionamiento cerebral alterado.

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Aquan-Assee, Jasmin Soylin Elizabeth. "Induced pain : cognitive and behavioural correlates." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28574.

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Cognitive processes have recently received considerable attention in studies of pain. Belief systems, coping mechanisms, perceptions of control and self-efficacy, and other cognitive systems appear to play a central role in determining individual differences to painful events (Rollman, 1983; Turk, Meichenbaum & Genest, 1983; Weisenberg, 1984). The present investigation sought to examine the cognitive and behavioural relationships that are associated with individual differences in responses to painful stimuli. Sixty female undergraduate psychology students participated in the experimental pain induction procedure which used the cold pressor test as the noxious stimulation. To gain a broad assessment of the different factors that may be characteristic of differences in response to pain, tolerant subjects were contrasted with less tolerant subjects on a variety of self-report, cognitive and behavioural - facial expression - measures. As part of the assessment procedure, subjects completed measures of state anxiety, self-efficacy to withstand pain, and a questionnaire involving a retrospective analysis of cognitive techniques. Half of the subjects were interviewed regarding their cognitions concerning the cold pressor task both pre and post their immersion, and the other half were interviewed post only. Transcriptions were coded independently of pain tolerance status. Subjects' facial expressions were videotaped during the cold pressor task and coded using the Facial Action Coding System (FACS) developed by Ekman and Friesen (1978). It was hypothesized that dysfunctional cognitions, lack of effective coping activity, amplification of sensory intensity and affective discomfort and high levels of facial activity would characterize subjects who were less tolerant of the induced pain. The distribution of the endurance times to the cold pressor task confirmed past observations that subjects cluster into two major groups of high and low tolerance (Turk et al. 1983). The results confirmed the major hypotheses that there are cognitive and self-report differences between pain tolerance groups. In comparison to tolerant subjects, less tolerant subjects had lower scores of perceived self-efficacy to withstand pain, higher scores for both sensation and discomfort ratings, retrospectively reported having experienced more pain, and made more accurate estimates of their duration in the cold water. Less tolerant subjects also reported more dysfunctional cognitions during the cold pressor task and reported using effective coping techniques to a lesser extent than tolerant subjects. Major differences between the tolerance groups also appeared in the length of post-test interviews. Tolerant subjects had much lengthier interviews at the post-test than less tolerant subjects. A discriminant analysis revealed that self-efficacy beliefs during the experimental task and the length of the post-test interviews were the most important discriminators between the groups. These results highlight the role of cognition in individual differences in pain tolerance. These results also suggest that low pain tolerance subjects may be better conceptualized as being ineffective and overwhelmed in their attempts to cope with pain which supports the current notion that cognitive based therapies may be the key in managing and alleviating pain states. No support was found for the hypothesis that subjects of differing pain tolerance thresholds would be characterized by differences in facial activity. Facial actions associated with pain in the present study were similar with facial expressions in previous studies (cf. Craig & Patrick, 1985; Hyde, 1986; Swalm, 1987). Contrary to previous results (Craig & Patrick, 1985), measures of facial expression increased over exposure time similarly to self-report. High levels of facial expression were associated with low levels of self-report of coping cognitions assessed at the post-test and with shorter post-test interviews.
Arts, Faculty of
Psychology, Department of
Graduate

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Laugesen, Nina. "Cognitive correlates of worry in adolescents." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ54277.pdf.

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Lawrence, Emma Jane. "Empathy : the cognitive and neural correlates." Thesis, King's College London (University of London), 2004. https://kclpure.kcl.ac.uk/portal/en/theses/empathy--the-cognitive-and-neural-correlates(c51470db-878c-4097-8ee4-7eca7d64aa46).html.

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Kerr, J. S. "Eye movement correlates of cognitive processes." Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381065.

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Belen, Hacer. "Emotional and cognitive correlates of hope." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/40773.

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This thesis outlines and details work conducted to understand the relationship between the components of hope and a range of trait-like emotional and cognitive constructs. Seven studies were conducted to explore these relationships. In this regard, the first study aimed to illuminate the theoretical and empirical underpinnings of trait agency-trait pathways in terms of Big-Five Personality theory. The second study examined the association between dimensions of hope and trait Emotional Intelligence, which is emotion-related perceptions located at the lower level of the personality hierarchy. The third study attempted to elaborate on the nature of the link between hope components and indicators of psychological well-being. To examine concepts related to cognitive aspects, the current thesis adopts the construct of executive functioning (EF), which is well-established in the heart of cognitive psychology. In addition, the fourth study examined the association between the dimensions of hope (agency and pathways) and five self-report EFs, namely Motivational Drive, Impulse Control, Empathy, Organization and Strategic Planning. The fifth study explored whether performance as an objective measure of Planning demonstrates significant links and correlations with agency and pathways. An additional study was conducted to examine whether selected self-report EF test (EFI) relates to objective measures of Planning, TOL-R. The final study investigates the relationship between agency-pathways and three central and critical objective measures of executive functioning; e.g. Stroop, Corsi Block-Tapping, and Switcher tasks. The findings regarding emotional constructs demonstrated that trait agency is associated with traits related to Conscientiousness, the EI factor of Well-Being, Environmental Mastery and Self-Acceptance as aspects of psychological well-being. In contrast, pathways thinking is associated with a number of traits related to the Big-Five interpersonal global traits that inform personality, i.e. Extraversion and Agreeableness, the EI factor of Sociability, Autonomy and Personal Growth, as aspects of psychological well-being. To assess cognitive constructs, agency is associated with self-reported Motivational Drive, Empathy, Organization and Strategic Planning, while pathways is associated with Strategic Planning. This association was not confirmed by objective EF measures. Findings provided by studies of hope and EF highlight the presence of a link between targeted EFs in self-report questionnaires, but not in objective measures.

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Bermudez, Patrick. "The neural correlates of absolute pitch." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21968.

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The unusual ability of absolute pitch (AP) affords us the opportunity to study a circumscribed behaviour which can be clearly operationalized and requires complex cognitive function in its execution. It serves as a model for a number of perceptual and mnemonic functions as well as developmental interactions between biological predispositions and specific training. This dissertation focuses mainly on the elucidation of its neural substrates. The work is divided into five chapters. Chapter 1 reviews and criticises what is known about the developmental, behavioural, anatomical and functional characteristics of AP. Chapter 2 describes the design and implementation of a computerized test of absolute pitch and resulting data for 51 musicians, 27 of whom self-reported as AP possessors. The test revealed differences in accuracy and timing for C Ionian diatonic versus non-diatonic notes and a range of performance, from perfect to random, including a substantial number of intermediate proficiencies. Chapter 3 details a series of anatomical explorations which seek to improve our understanding of the structural correlates of AP. Cortical thickness measures and voxel-based morphometry (VBM) were applied to the same magnetic resonance imaging data set of 71 musicians (27 with absolute pitch) and 64 non-musicians. Cortical thickness was greater in musicians with peaks in the superior temporal gyri and the dorsolateral frontal cortices. VBM of grey-matter classified voxels yielded a strongly right-lateralized focus of greater grey matter concentration in musicians, centered on the posterolateral aspect of Heschl's gyrus. Contrasts of absolute pitch possessors and non-possessors showed significantly thinner cortex among possessors in a number of areas, including the posterior dorsal frontal and ventral premotor cortices. Chapter 4 describes a functional study which tests a hypothesis generated from a previous experiment about the implication of posterior dorsolateral
La capacité peu commune de l'oreille absolue (OA) nous offre l'opportunité d'étudier un comportement circonscrit qui peut être opérationnalisé et exige un traitement cognitif complexe pour son exécution. L'OA sert de modèle pour un certain nombre de fonctions perceptuelles et mnémoniques ainsi que pour des interactions entre une prédisposition biologique et une formation spécifique. Cette thèse se concentre principalement sur l'élucidation de ses substrats neuronaux. Le travail est divisé en cinq chapitres. Le premier revoit et critique la littérature pertinente aux caractéristiques développementales, comportementales, anatomiques, et fonctionnelles de l'OA. Le deuxième chapitre décrit la conception et la mise en œuvre d'un test informatisé de l'OA aboutissant en données comportementales pour 51 musiciens, dont 27 prétendaient avoir l'OA. Le test a révélé une meilleure précision et vitesse d'identification de notes diatoniques en Do majeur versus notes non-diatoniques et une gamme de performance, entre parfaite et au hasard, y compris un nombre important d'aptitudes intermédiaires. Le troisième chapitre présente une série d'explorations anatomiques qui visent à améliorer notre compréhension des corrélats structurels de l'OA. Des analyses de mesures d'épaisseur corticale et de morphométrie à base de voxel (VBM) ont été appliquées aux mêmes données d'imagerie par résonance magnétique (IRM) de 71 musiciens (27 avec l'OA) et 64 non-musiciens. L'épaisseur corticale était plus forte parmi les musiciens avec des focus au gyrus temporal supérieur et au cortex frontal dorsolatéral. Une analyse VBM de matière grise a produit une différence entre musiciens et non-musiciens centrée sur l'aspect postérolatéral du gyrus de Heschl dans l'hémisphère droit. Un contraste de possesseurs et non-possesseurs de l'OA a révélé plusieurs aires de cortex plus minces chez les possesseurs, notamment les aires postérieure

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Frost, Robert B. "QEEG Correlates of Cognitive Deficits in Multiple Sclerosis During Targeted Cognitive Tasks." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4047.

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Multiple sclerosis (MS) is the most common neurological disorder of young adulthood and is often associated with cognitive impairment and emotional dysfunction. Due to the nature of the disease, the cognitive deficits in MS are often variable in their presentation, and consist of deficits in processing speed, attention, working memory, and executive functioning. The purpose of the present study was to explore common methods of documenting MS-related cognitive deficits, to elucidate the relationship between the cognitive deficits seen in MS and physiological markers of cognitive functioning (i.e., quantitative EEG), and to analyze the relationship between cognitive deficits and mood dysfunction in MS. There were 26 participants diagnosed with remitting-relapsing multiple sclerosis and 18 age, sex, and education matched controls. Results of cognitive testing indicated deficits in gross cognitive functioning, language, attention, processing speed, working memory, and executive functioning. A MANOVA encompassing group, task (PASAT and SPT) and load (light and heavy) showed significant group and load effects, but no main effect of task. The MS group performed worse than the controls and both groups performed better on the light load than the heavy load. Post hoc analysis indicated that performance on the PASAT 3 second trial was worse than on the PASAT 2 second trail compared to controls. Given that the PASAT 3 trial is theoretically easier than the PASAT 2 trial and that the PASAT 3 was administered first, the above results likely reflect learning effects. A Repeated Measures ANCOVA encompassing EEG and cognitive data (PASAT and SPT) indicated group-level differences on task performance, and suggested that at rest mean peak alpha frequency (PAF) is associated with performance on the PASAT, but not the SPT. EEG coherence during cognitive tasks was reduced between short-range connections in the theta, alpha, and beta frequency bins and enhanced in a limited number of long-range, anterior to posterior connections in the theta frequency bin in the MS group compared to controls. Finally, the MS participants had significantly more symptoms of depression and anxiety compared to normal controls. A hierarchical multiple regression analysis suggested that cognitive functioning is deleteriously affected by depression and anxiety. Overall, the results of this study substantiate the feasibility of utilizing QEEG as a physiological indicator of cognitive and cortical dysfunction in MS and show the importance of recognizing depression and anxiety and their contributions to cognitive deficits in individuals with MS.

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Fernández-Andújar, Marina. "Neuroimaging correlates of cognitive functioning in cerebrovascular disease." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/290852.

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Cerebrovascular diseases (CD) are the third most common cause of death and the leading cause of disability in adults in developed countries (Carmichael, 2012; World Health Organization, 2004). Specifically, ischemic stroke and white matter lesions (WML) often result in multiple neurological, cognitive impairment and behavioral and emotional disorders (Gorelick et al., 2011; Troncoso et al., 2008). Strokes are responsible for damage in the core of the ischemic lesion but may also cause alterations in remote areas from the primary ischemic lesion. The thalamus is a key structure in the cortico-subcortical circuits (Alexander et al., 1986; Byne et al., 2009) and is involved in multiple cognitive functions (Herrero et al., 2002; Sherman, 2005) especially in functions executive, one of the most affected cognitive domains after suffering a stroke. Although it is known that the cortico- subcortical circuits are involved in cognitive functions, to date their neuroimage correlates are unknown. The overall objective of this thesis was to study the effects of a disruption in the cortico-subcortical circuits, due to a direct or remote damage, in executive functions. For the study of remote thalamic abnormalities we use the technique of diffusion tensor image (DTI) for both ischemic stroke and WML. Moreover, due to attention and cognitive inhibition are one of the most important functions of executive domain, we studied the relationship between a specific white matter (WM) tract -called Front aslant Tract (FAT)- and these functions. The study results showed that remote thalamic microstructural abnormalities secondary to a cerebrovascular lesion can occur in both ipsilateral and contralateral thalamus, in healthy subjects with WML and in patients with cerebral ischemic stroke. These thalamic abnormalities may be related to a disruption in the cortico-subcortical circuits associated with executive dysfunction. In addition, the right FAT is involved in attention and response inhibition functions in community-dwelling subjects and participants with ischemic stroke. In conclusion, the results obtained in this thesis suggest that stroke can affect the cortico-subcortical circuits through thalamic microstructural abnormalities and these could be related to cognitive dysfunction. Finally, the novel technique of DTI can play an important role in understanding the cognitive functioning in both ischemic stroke and WML.
Los accidentes cerebrovasculares (ACV) son la tercera causa más común de muerte y la causa principal de discapacidad en adultos en los países desarrollados (Carmichael, 2012; Organización Mundial de la Salud, 2004). Concretamente, el ictus isquémico y las lesiones de sustancia blanca (LSB) frecuentemente dan lugar a múltiples secuelas neurológicas, deterioro cognitivo y alteraciones conductuales y emocionales (Gorelick et al., 2011; Troncoso et al., 2008). Los ACV son responsables de daño en la zona primaria de la lesión isquémica pero también pueden producir alteraciones en áreas remotas a ésta. El tálamo es una estructura clave en los circuitos cortico-subcorticales (Alexander et al., 1986; Byne et al., 2009) y está involucrado en múltiples funciones cognitivas (Herrero et al., 2002; Sherman, 2005) especialmente en las funciones ejecutivas, uno de los dominios cognitivos más afectados después de sufrir un ACV. Aunque se sabe que los circuitos cortico-subcorticales están implicados en las funciones cognitivas, hasta la fecha sus correlatos de neuroimagen se desconocen. El objetivo general de esta tesis ha sido estudiar los efectos de una interrupción en los circuitos cortico-subcorticales debido a una lesión directa o remota en las funciones ejecutivas. Para el estudio de las anomalías talámicas remotas usamos la técnica de la Imagen por Tensor de Difusión (ITD), tanto para el ictus isquémico como para las LSB. Además, dado que la atención y la inhibición cognitiva son una de las funciones más importantes de las funciones ejecutivas, estudiamos la relación entre un tracto de sustancia blanca (SB) -llamado Frontal Aslant Tract (FAT)- y estas funciones. Los resultados de los estudios mostraron que anomalías secundarias microestructurales talámicas remotas a la lesión cerebrovascular pueden ocurrir tanto en el tálamo ipsilateral como en el tálamo contralateral, en sujetos sanos con LSB y en pacientes con un ictus cerebral isquémico. Estas anomalías talámicas pueden estar relacionadas con una disrupción en los circuitos cortico-subcorticales asociado con disfunción ejecutiva. Además, en sujetos de la comunidad y con un ictus isquémico, el FAT derecho está implicado en atención e inhibición de respuesta. En conclusión, los resultados obtenidos en la presente tesis doctoral sugieren que los ACV puede afectar los circuitos cortico-subcortical a través de anomalías microstructurales talámicas y éstas podrían estar relacionadas con la disfunción cognitiva. Finalmente, la novedosa técnica de la ITD puede tener un papel relevante en el conocimiento del funcionamiento cognitivo tanto en el ictus isquémico como en las LSB.

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Hallin, Nathalie. "Cognitive Dissonance : Neural Correlates and New Theoretical Approaches." Thesis, Högskolan i Skövde, Institutionen för kommunikation och information, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-7173.

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Cognitive dissonance has traditionally been defined as the negative affective state which accompanies inconsistent cognitions and motivates one to make the cognitions consistent. This thesis critically evaluates two theories about cognitive dissonance. The action-based model of dissonance argues that inconsistent cognitions have the potential to interfere with effective and unconflicted action. The new look model of dissonance, contradicting the traditional definition of dissonance, argues that it is aversive consequences rather than inconsistent cognitions that cause dissonance. Recent studies investigating the neural correlates of dissonance show that parts of anterior cingulate cortex and prefrontal cortex seem to be involved in the dissonance process. One of the major predictions of the new look model of dissonance has been undermined by recent evidence. In contrast, the action-based model of dissonance is supported by recent studies.

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Roberts, Richard Edward. "On Brain Correlates of Cognitive and Motor Control." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508626.

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Al-Yahya, Emad S. "Neural correlates of cognitive motor interference while walking." Thesis, Oxford Brookes University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543804.

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Bergström, Natalie. "The neural correlates of cognitive reappraisal stress resilience." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-15562.

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Resilience refers to the fact that some individuals cope well with stressful experiences. Many factors contribute to this sort of resilience, such as the early environment, the serotonin transporter gene (5-HTTPLR), the hypothalamic-pituitaryadrenal (HPA) axis, the sympathetic-adrenal medullary (SAM) axis, and emotion regulation techniques. The aim of this thesis is to investigate which factors contribute to resilience, with a particular focus on the emotion regulation technique of cognitive reappraisal. The results show that the prefrontal cortex (PFC) and amygdala each play a crucial role when it comes to stress regulation. Studies have found that the PFC inhibits the amygdala response, but that the PFC is vulnerable to exposure to chronic stress. As a result, the PFC might fail to inhibit the amygdala response. Individuals who use cognitive reappraisal techniques – which has been associated particularly with frontal and parietal brain activity – seem to be less prone to this sort of problem, and, as a result, more resilient to stress.

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WILDER-WILLIS, KELLY ELIZABETH. "COGNITIVE CORRELATES OF PSYCHOSOCIAL OUTCOME IN BIPOLAR DISORDER." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1017754637.

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Craig, Douglas E. "Perfectionism in Social Anxiety: Cognitive and Behavioral Correlates." DigitalCommons@USU, 1993. https://digitalcommons.usu.edu/etd/6069.

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The purpose of this study was to examine the relationship between perfectionism and social anxiety in general as well as social phobia, specifically. Subjects completed the Personal Standards Scale, the Fear of Negative Evaluation scale, and the Social Phobia and Agoraphobia Inventory. Results indicated that neurotic perfectionism is positively associated with both general social anxiety and social phobia. Moreover, the neurotic elements of perfectionism -- "concern over making mistakes" and "doubts about actions" -- appeared to be better predictors of social anxiety than high performance standards alone. Differences between social phobia and social anxiety secondary to agoraphobia as related to perfectionism were addressed, and directions for future research are discussed.

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Kroeger, Lori A. "Neural Correlates of Error Detection in Math Facts." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1353088326.

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Budolfson, Katie. "Clinical Correlates of the Alzheimer's Questionnaire." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/623236.

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A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.
Informant‐based assessments of cognition and function are commonly used to differentiate individuals with amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease (AD) from those who are cognitively normal (CN). However, determining the extent to which informant‐based measures correlate to objective neuropsychological tests is important given the widespread use of neuropsychological tests in making clinical diagnoses of aMCI and AD. The aim of the current study is to determine how well the Alzheimer’s Questionnaire (AQ) correlates with objective neuropsychological tests. Results showed that the AQ correlated strongly with the Mini Mental State Exam (r = ‐0.71) and the Mattis Dementia Rating Scale‐2 (r = ‐0.72), and moderate correlations were noted for the AQ with memory function (Rey Auditory Verbal Learning Test Delayed Recall, r = ‐0.61) and executive function (Trails B, r = 0.53). The AQ also correlated moderately with language function (Boston Naming Test 30‐Item, r = ‐0.44), but showed a weak correlation with visuospatial function (Judgment of Line Orientation, r = ‐0.28). The AQ also correlates particularly well with cognitive screens, showing the strongest correlations with the MMSE (r = ‐0.71) and the DRS‐2 (r = ‐0.72). The findings of this study suggest that the AQ correlates well with several neuropsychological tests, particularly those that assess the domains memory and executive function. These results lend further support to the validity of the AQ as a screening instrument for cognitive impairment as it correlates well with neuropsychological measures used to make clinical diagnoses of aMCI and AD.e sites become involved, thus providing significant feedback for possible course revision.

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Thomson, Lisa, and University of Lethbridge Faculty of Arts and Science. "Sickness-induced cognitive dysfunction : molecular, physiological, and behavioural correlates." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2004, 2004. http://hdl.handle.net/10133/623.

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Glasser, Martin. "Neuroanatomical correlates of cognitive dysfunction in obstructive sleep apnoea." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/44371.

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Obstructive sleep apnoea (OSA) has been reported to be associated with brain hypotrophy and cognitive dysfunction; however, whether these normalise after treatment is unclear. The overall aim of this thesis is to investigate the relationship between OSA and brain structure using FreeSurfer (a new automated technique that reliably measures brain structures). I have investigated changes in brain morphology and the newly described phenomenon in OSA of ischaemic preconditioning. Chapters 4 and 5 will also assess brain structural response to CPAP, and investigate the association between brain structure and cognitive function in OSA. Chapter 3 reports an observational study investigating brain structure. FreeSurfer analysis of magnetic resonance imaging (MRI) found OSA patients had hypertrophy in the right hippocampus (p=0.03) and right choroid plexus (p=0.02) but hypotrophy of the corpus callosum (p=0.04) compared to healthy controls. Chapter 4 reports a randomised controlled trial of CPAP in OSA. At baseline hypotrophy was seen in the corpus callosum (p=0.03) and pallidum (p=0.03) of OSA patients compared to healthy controls. Hypertrophic changes in the right thalamus were seen in the CPAP group after 1 month (p=0.06), associated with improvement in verbal memory (p=0.04). Chapter 5 reports a randomised controlled trial of CPAP in older patients with OSA. A significant decrease in left fimbria volume was seen in the CPAP group (p=0.01). A significant increase in the left presubiculum volume was seen in the best supportive care group (p=0.03). No hippocampal hypertrophy was seen in the CPAP group. In summary, young and middle-aged OSA patients had evidence of brain hypotrophy, but also areas of hypertrophy that may signify dendritic sprouting and increased connectivity as a result of ischaemic preconditioning. This allows recovery of brain hypotrophy after CPAP treatment. This was not seen in older OSA patients suggesting an age-related difference which may have implications for OSA treatment in older people.

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Muller, Alana Lauren. "Neurological Correlates of the Dunning-Kruger Effect." CSUSB ScholarWorks, 2019. https://scholarworks.lib.csusb.edu/etd/810.

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The Dunning-Kruger Effect is a metacognitive phenomenon in which individuals who perform poorly on a task believe they performed well, whereas individuals who performed very well believe their performance was only average. To date, this effect has only been investigated in the context of performance on mathematical, logical, or lexical tasks, but has yet to be explored for its generalizability in episodic memory task performance. We used a novel method to elicit the Dunning-Kruger Effect via a memory test of item and source recognition confidence. Participants studied 4 lists of words and were asked to make a simple decision about the words (source memory, i.e. Is it manmade? Is it alive?). They were later tested on their episodic memory and source memory for the words using a five-point recognition confidence scale, while electroencephalography (EEG) was recorded. After the test, participants were asked to estimate the percentile in which they performed compared to other students. Participants were separated into four quartiles based on their performance accuracy. Results showed that participants in all four groups estimated the same percentile for their performance. Participants in the bottom 25th percentile overestimated their percentile the most, while participants in the top 75th percentile slightly under-estimated their percentile, exhibiting the DKE and extending its phenomenon into studies of episodic memory. Groups were then re-categorized into participants that over-estimated, correctly estimated, and under-estimated their percentile estimate. Over-estimators responded significantly faster than under-estimators when estimating themselves as in the top percentile and they responded slower when evaluating themselves as in the bottom percentile. EEG first revealed generic scalp-wide differences within-subjects for all memory judgments as compared to all self-estimates of metacognition, indicating an effective sensitivity to task differences. More specific differences in late parietal sites were evident between high percentile estimates and low percentile estimates. Between-group differences were evident between over-estimators and under-estimators when collapsing across all Dunning-Kruger responses, which revealed a larger late parietal component (LPC) associated with recollection-based processing in under-estimators compared to those of over-estimators when assessing their memory judgements. These findings suggest that over- and under-estimators use differing cognitive strategies when assessing their performance and that under-estimators use less recollection when remembering episodic items, thereby revealing that episodic memory processes are playing a contributory role in the metacognitive judgments of illusory superiority that are characterized by the Dunning-Kruger Effect.

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21

Overduin, Simon Alexander. "Neuromuscular modularity and behavioral correlates of motor control." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/33215.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, 2006.
Includes bibliographical references (p. 259-276).
I studied organizational principles that may subserve the control and learning of forelimb movements. Among these principles, I focused on muscular coordination patterns, motor cortical excitability, and sensorimotor interactions. I found that muscle activity in grasping and reaching behaviors could be reconstructed by linear combinations of a small number of time-varying muscle synergies, each fit with coefficients unique to the behavior. However, the generalization of these synergies between behavioral conditions was limited, in part by the sensitivity of the extraction algorithm to stereotyped muscular relations within contrasted conditions. In reaching studies designed to assist or resist different movement directions, I found a gradual change in the structure, as well as recruitment, of synergies. When a perturbation was targeted to the activity within a single muscle, I found a transient, relative suppression of this muscle in response to descending motor commands. In other motor cortical microstimulation experiments, I confirmed that long-train microstimulation is able to evoke complex, convergent movements. Even during highly-trained reaching movements, I found that there was relatively little invariance of the muscular patterns in relation to kinematic variables coding for the hand's displacement and velocity.
(cont.) In two studies examining the kinematic consequences of modulating cortical excitability, I either infused tissue plasminogen activator into monkey cortex or applied transcranial magnetic stimulation to human cortex, either while or before each adapted to a clockwise force field. In both cases basal motor performance was spared, but each manipulation appeared to be associated with disruptions of subjects' ability to retain, improve, or recall recent adaptations. Among other human studies, I investigated the interaction of dynamic adaptation and sequence learning, and found that simultaneous acquisition of a force field and a sequence does not impair performance on either but may have enabled subjects to tune in to, and chunk, their movements. I found that motor consolidation may be dependent on the more effortful learning enabled by catch-trial interruptions of practice on a novel condition. Finally, I used functional imaging and manual cutaneous stimulation to show that the hemodynamic response was biased according to receptor density but generally non-somatotopic and distributed throughout sensorimotor cortex.
by Simon Alexander Overduin.
Ph.D.

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22

Stanek, Kelly Marie. "Neuropsychological Correlates of Body Image Disturbance." Kent State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=kent1239059135.

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23

Allen, Micah G. "Linguistic correlates of psychopathology in autobiographical narrative." Honors in the Major Thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1056.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.
Bachelors
Sciences
Psychology

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24

Achim, Amélie M. "Neural correlates of associative and item memory." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80160.

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Dissociation between memory for individual items and memory for associations has been reported in behavioral neurosciences, clinical populations and cognitive studies. At the brain level, this dissociation could reflect distinct patterns of activation for encoding and/or retrieval of items and associations. We used event-related functional Magnetic Resonance Imaging to assess neural correlates of item and associative encoding and retrieval in eighteen healthy subjects. During encoding, subjects memorized doubles (two identical images) and pairs (two different images). During retrieval, subjects made item recognition judgments (old versus new items) and associative recognition judgments (intact versus rearranged pairs). Greater hippocampal activation was observed for associative relative to item encoding, but also for item relative to associative recognition. This pattern of hippocampal activation is consistent with previous neuroimaging studies of associative encoding, but also suggests that at retrieval other processes such as novelty detection could recruit the hippocampus to a greater extent than associative recognition. In the prefrontal cortex, we observed right and left activation for associative and item encoding, respectively. At retrieval, the opposite pattern was observed with left prefrontal activation for associative and bilateral activation for item recognition. This pattern of prefrontal activation shows the implication of the prefrontal cortex in memory for both types of material, although with a different lateralization. Overall, these results show the importance of examining the memory stages when comparing neural correlates of item and associative memory.

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Nejasmic, Jelica [Verfasser]. "Cognitive and neuronal correlates of spatial belief revision / Jelica Nejašmić." Gießen : Universitätsbibliothek, 2015. http://d-nb.info/1069065307/34.

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26

Kauhanen, M. L. (Marja-Liisa). "Quality of life after stroke:clinical, functional, psychosocial and cognitive correlates." Doctoral thesis, University of Oulu, 1999. http://urn.fi/urn:isbn:9514254279.

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Abstract Depression is a common consequence of stroke and it is known to be associated with deterioration of quality of life. However, only limited information is available on the relationships between depression and communicative and cognitive disorders. Moreover, the present knowledge of the determinants of the domains of quality of life is limited, and little is known of e.g. the changes in sexual behaviour of stroke patients and their spouses. This prospective study was carried out to evaluate the prevalence of post-stroke depression and aphasia and to study their interrelationships and neuropsychological and functional correlates. The particular aim of the study was to investigate the domain-specific quality of life, and to assess its clinical and sociodemographic correlates, and to study the impact of stroke on the sexual functions of stroke patients and their spouses. The study consisted of 156 first-ever stroke patients. Depression was diagnosed in 53% of the patients at 3 months and in 42% of the patients at 12 months post-stroke according to DSM-III-R-criteria. One third of the patients were aphasic, 70% of them at 3 months and 62% at 12 months after stroke suffering from depression. Among the aphasic patients the prevalence of major depression increased from 11% to 33% during the 12 months follow-up. There was an association between post-stroke depression and cognitive impairment, the domains most likely to be defective being memory, non-verbal problem solving, and attention and psychomotor speed. The non-verbal neuropsychological test performance in the aphasic patients was significantly inferior to that of the patients with dominant hemisphere lesion without aphasia. The quality of life of the patients was low at 3 months after the stroke, and it did not improve during the follow-up of a year. The test domains most often impaired were Physical functioning, Physical role limitations, Vitality and General health. Depression, although mostly minor, and being married emerged as significant independent contributors to low score value of Vitality and Physical role limitations. All the analyzed aspects of sexuality were commonly decreased as a consequence of stroke both in the patients and their spouses. Nocturnal erections were impaired in 21 (55%) of the male patients. The present results demonstrate that more than half of the patients after stroke suffer from depression and the frequency of major depression seems to increase over time, especially among the aphasic patients. Both depression and aphasia increase the liability of cognitive deficits. Stroke affects various dimensions of quality of life extensively, and the most important determinants entailing low quality of life seem to be depression, and, interestingly, being married. As a part of quality of life, sexual function and satisfaction with sexual life are impaired both in stroke patients and spouses. These findings call for multidimensional evaluation of stroke patients and provide new challenges for stroke rehabilitation.

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27

Mangvwat, Solomon Elisha. "Cognitive and decoding correlates of reading comprehension in Nigerian children." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/13673.

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The aim of this thesis was to better understand English as second language Nigerian children’s reading comprehension attainment, the first such study to be conducted in Nigeria. In the thesis three studies were conducted to investigate the influence of cognitive and decoding/reading skills on the children’s reading comprehension attainment, namely the preliminary study (Chapter-3) with one primary school in Nigeria, the main study (Chapter-4) with 13 state-run primary schools, and the control study (Chapter-5) including four primary schools in London, respectively. It was found that English as second language children’s reading comprehension performance is significantly influenced by cognitive, decoding and chronological age. The development of cognitive skills which is necessary for success in reading comprehension development is also dependent upon chronological age. That is, age-related increase in cognitive skills brings about increased engagement and more efficient reading comprehension attainment in the children. The normal cognitive development of the children had a positive role also on the children’s performance on language tests necessary for text comprehension. The study found that school socioeconomic background played a significant impact in the performance of Nigerian English as second language children – the better the socioeconomic background of the school the higher the reading comprehension attainment of the children. Furthermore gender was not a factor in the performance and development of reading comprehension by English as Second Language Nigerian children. This implies that parents, teachers and schools motivate and support children irrespective of being boys or girls to realise their full potentials without any discrimination. Having reviewed few theories of reading acquisition/development, the Simple view of reading (SVR) was found to be more appropriate for adoption in this study of Nigerian English as second language children’s reading comprehension attainment. The theory postulates that text comprehension is achieved when children have decoding skills and linguistic comprehension knowledge. The results obtained in Chapters 3 and 4 were in line with the Simple view of reading’s assertion – text comprehension depends on decoding and cognitive skills.

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28

Rudra, Aruna. "Cognitive correlates of poor and advanced reading abilities in children." Thesis, University of Essex, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411299.

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29

Meggs, Jennifer. "Examining the cognitive, physiological and behavioural correlates of mental toughness." Thesis, Teesside University, 2013. http://hdl.handle.net/10149/315388.

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Mental toughness has received extensive research attention in recent years because of its intuitive and theoretical association with successful performance. However, several significant omissions in understanding remained. This thesis aimed to address these gaps through various research approaches and methodologies, collectively resulting in a biopsychological perspective. The primary objectives were to provide a more holistic perspective of mental toughness and generate quantitative support for the various biological (2D:4D) cognitive-affective (self-structure), physiological (cortisol response) and behavioural (performance) differences that have been associated with the construct. The findings suggested that mental toughness is a multifaceted construct and manifests in several areas of human functioning; specifically, a particular cognitive-affective profile may underlie mental toughness (they possess a positive self-concept and a particular self-structuring style, namely integration). Furthermore, levels of cortisol during a competitive event (a physiological indicator of perceived stress levels) were significantly negatively related to mental toughness, suggesting that mentally tough individuals have a reduced perception of threat in competitive situations (giving support for the notion that they perceive competition or stress as a potential challenge for personal growth and improvement). An objective marker of mental toughness was also supported; specifically, 2D:4D ratio (indicative of prenatal testosterone levels) related significantly with scores on a mental toughness scale, giving support for the biological underpinning of the construct and an objective marker of mental toughness. Finally, two case examples are provided to demonstrate the usability of these important markers (cognitive, biological and physiological) in an applied context.

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Pauls, Astrid. "Clinical, cognitive, and neuroimaging correlates of risk for postpartum psychosis." Thesis, King's College London (University of London), 2014. https://kclpure.kcl.ac.uk/portal/en/theses/clinical-cognitive-and-neuroimaging-correlates-of-risk-for-postpartum-psychosis(eb57e080-eb34-492c-bdc6-eb42bc5357f7).html.

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Although postpartum psychosis is a devastating and predictable disorder, it has received little attention in biological research. This is the first study assessing cognitive, emotional and neuroimaging correlates of women at risk of postpartum psychosis. We hypothesised that women “at risk” will show decreased brain activation in the dorsolateral prefrontal cortex in a working memory task and increased brain activation in the amygdala in a facial emotion processing task, compared to healthy controls, similar to that observed in bipolar disorder and psychoses unrelated to childbirth. Twenty-five women “at risk” (N=13 due to non-postpartum and N=12 due to postpartum episodes) were compared to 21 healthy women within the first year after delivery. Women took part in two study visits including clinical interviews and a magnetic resonance imaging (MRI) scan. We assessed working memory and emotional face processing using two functional MRI tasks and verbal memory using two behavioural tasks. Groups were matched on sociodemographic background and medical and obstetric history. Women “at risk” showed an activation increase of the midcingulate and temporal cortices compared to healthy controls, which was accompanied by deficits in working and verbal memory performance. Women with postpartum episodes, compared to healthy controls, showed a relative increase in activation to fearful faces in the left inferior frontal gyrus. This study provides preliminary evidence that women “at risk” of postpartum psychosis show cognitive impairments similar to those of patients with bipolar disorder and psychoses unrelated to childbirth. Women with postpartum episodes seem to differ in emotional processing from healthy controls, possibly indicating an increased emotional response to fear. These results represent a first step towards a better understanding of cognitive and emotional processes in postpartum psychosis. When validated in larger and longitudinal studies, they may help clinicians in developing individual management strategies and implementing targeted cognitive trainings or interventions.

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Pappaianni, Edoardo. "Shame on you! Cognitive mechanisms and neural correlates of shame." Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/252594.

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Shame is a self-conscious emotion that characterizes the life of all individuals. It arises when a moral violation occurs and the person is judged negatively by others for a way of being that does not correspond to the standards of society. Although over the years it has been widely treated from a theoretical point of view, there are few attempts in the literature to approach it scientifically by psychologists and neuroscientists. Using an integrated approach, based on neuroimaging, behavioral and neuropsychological investigations, in this thesis we aimed to investigate what are the cognitive mechanisms through which shame operates and what are its neural bases. After an initial theoretical introduction in which a novel model of shame functioning is proposed, two behavioral studies are presented in which an innovative experimental paradigm of shame elicitation has been validated and tested. Subsequently, the single-case of a patient with rare bilateral amygdala damage has been described. Since this region is notoriously crucial for emotional aspects, we tested the possibility that an amygdala injury could also lead to deficits in perception and recognition of shame. Afterward, to investigate if shame had its own specific neural activation map, a meta-analysis on functional studies in the literature that investigated the neural bases of shame and guilt (another self-conscious emotion) has been carried out. Finally, given the heterogeneity of the paradigms included in the meta-analysis, we run an fMRI study using our novel paradigm in order to detect shame neural signal. In general, by combining different methodologies, this work allowed us to approach shame from different perspectives, from simple elicitation and behavioral measurement to its neural basis. This has added a piece of knowledge in the field of affective neuroscience regarding a moral emotion (i.e. shame) that is fundamental to individual well-being within our society.

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Chen, Yu. "Cerebellar contributions to cognitive changes in frontotemporal dementias." Thesis, The University of Sydney, 2020. https://hdl.handle.net/2123/21825.

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Mounting evidence indicates that the impact of cerebellar damage extends beyond motor function, and also affects cognition. Frontotemporal dementia (FTD) is associated with heterogeneous patterns of cortical atrophy, primarily affecting the frontal and/or temporal lobes. Previous research has also found cerebellar changes in FTD. The cognitive role of the cerebellum in FTD, however, remains unclear. This thesis, therefore, examines cerebellar contributions to cognitive changes using a combination of behavioural and neuroimaging approaches in the three main FTD subtypes, each with distinct clinical cognitive profiles: behavioural-variant FTD (bvFTD), semantic dementia (SD), and progressive nonfluent aphasia (PNFA). The results from this thesis demonstrated that the cerebellum is affected in all the three FTD subtypes, with syndrome-specific patterns of cerebellar changes across subtypes (Chapters 2, 4-6). These cerebellar changes are associated with cognitive performance in FTD. Novel evidence of an independent cerebellar contribution and an interaction between the cerebellum and the cerebrum, and their relations with cognition in FTD subtypes are also reported (Chapters 4-7). Importantly, cerebellar atrophy progresses over time and is associated with cognitive decline with disease progression (Chapter 6). The expansion of GGGGCC hexanucleotide repeat in the non-coding intronic region of the chromosome 9 open reading frame 72 gene (C9orf72) is the most common genetic cause of familial FTD. Comparison between FTD patients with and without C9orf72 gene expansion revealed distinct patterns of cerebellar grey matter atrophy between groups, and this cerebellar atrophy is differentially associated with cognitive performance (Chapter 7). Together, the results of this thesis uncover syndrome-specific cerebellar changes across FTD syndromes, which in turn relate to discrete cognitive dysfunctions. These findings extend the understanding of the cerebellum and point to its involvement across an array of processes beyond the domain of motor function. From a clinical perspective, these novel findings bring new insights into the mechanisms mediating FTD symptomatology, and have important implications for disease management, intervention and wellbeing for both patients and carers.

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33

Farrell, Lara J., and n/a. "Obsessive-Compulsive Disorder Across the Developmental Trajectory: Clinical Correlates and Cognitive Processing of Threat." Griffith University. School of Applied Psychology, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040513.132648.

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Controlled scientific research into obsessive-compulsive disorder (OCD) in adulthood has considerably progressed over the past two decades; however, current research into childhood OCD is still in its infancy by comparison. As a result, current psychological conceptualisations of OCD during childhood, including approaches to treatment, are almost entirely based on adult models of the disorder. Previous research however, examining the clinical phenomenology of OCD has provided some evidence that OCD might be associated with different clinical correlates at different stages of development. In particular, there appears to be a bimodal distribution in terms of the age of onset of the disorder, a male predominance during childhood and adolescence compared to adulthood, stronger familial aggregation of OCD in early onset cases, and differences in the types of symptoms and the patterns of comorbidity across age groups. The first study aimed to assess the developmental continuity in clinical correlates of OCD across 3 distinct age groups, including; children (n = 40), adolescents (n = 44) and adults (n = 41). It was hypothesised that the sample of children would be predominantly male, and would have a higher familial aggregation of OCD and/or anxiety/depression in first-degree relatives. It was further hypothesised that there would be significant age-related differences in terms of specific symptoms, patterns of comorbidity, OCD severity, functional impairment, and level of insight and distress. The results of this study supported the developmental heterogeneity hypothesis, with significant differences occurring across age groups on a number of clinical features of OCD including age at onset, symptoms experienced, comorbidity, severity, insight and impairment. The recognition of developmental differences in clinical features of OCD will assist in the accurate assessment and diagnosis of the disorder, and will allow for refinement of current treatment strategies to ensure treatments effectively target features of the disorder as it presents at different developmental stages. While the cognitive theory of OCD is one of the most widely accepted accounts of the maintenance of the disorder in adults, no study to date has systematically evaluated this theory across children, adolescents and adults with the disorder. Until empirical investigation examines the applicability of this theory to children and adolescents, we know very little about the cognitive processes associated with OCD during childhood or adolescence. The second study investigated developmental differences in the cognitive processing of threat in a sample of children (n = 34), adolescents (n = 39) and adults (n = 38) with OCD. Using an idiographic assessment approach, as well as self-report questionnaires, this study evaluated cognitive appraisals of responsibility, probability, severity, thought-action fusion (TAF), thought-suppression, self-doubt and cognitive control. It was hypothesised that there would be age related differences in reported responsibility for harm, probability of harm, severity of harm, thought suppression, TAF, self-doubt and cognitive control. Results demonstrated that children with OCD reported experiencing fewer intrusive thoughts, which were less distressing and less uncontrollable than those experienced by adolescents and adults with OCD. Furthermore, responsibility attitudes, probability biases and thought suppression strategies were significantly higher in adolescents and adults with OCD, compared to children. Cognitive processes of TAF, perceived severity of harm, self-doubt and cognitive control were found to be comparable across age groups. These findings suggest that some cognitive biases associated with OCD in adults, are in fact also associated with OCD during childhood and adolescence, however there remains some discontinuity across specific cognitive processes. For a developmentally sensitive theory of OCD, further investigation is clearly warranted into other possible age related maintenance factors of this disorder. Implications of these 2 empirical investigations are highlighted and directions for future research are discussed.

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34

Farrell, Lara J. "Obsessive-Compulsive Disorder Across the Developmental Trajectory: Clinical Correlates and Cognitive Processing of Threat." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/366531.

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Controlled scientific research into obsessive-compulsive disorder (OCD) in adulthood has considerably progressed over the past two decades; however, current research into childhood OCD is still in its infancy by comparison. As a result, current psychological conceptualisations of OCD during childhood, including approaches to treatment, are almost entirely based on adult models of the disorder. Previous research however, examining the clinical phenomenology of OCD has provided some evidence that OCD might be associated with different clinical correlates at different stages of development. In particular, there appears to be a bimodal distribution in terms of the age of onset of the disorder, a male predominance during childhood and adolescence compared to adulthood, stronger familial aggregation of OCD in early onset cases, and differences in the types of symptoms and the patterns of comorbidity across age groups. The first study aimed to assess the developmental continuity in clinical correlates of OCD across 3 distinct age groups, including; children (n = 40), adolescents (n = 44) and adults (n = 41). It was hypothesised that the sample of children would be predominantly male, and would have a higher familial aggregation of OCD and/or anxiety/depression in first-degree relatives. It was further hypothesised that there would be significant age-related differences in terms of specific symptoms, patterns of comorbidity, OCD severity, functional impairment, and level of insight and distress. The results of this study supported the developmental heterogeneity hypothesis, with significant differences occurring across age groups on a number of clinical features of OCD including age at onset, symptoms experienced, comorbidity, severity, insight and impairment. The recognition of developmental differences in clinical features of OCD will assist in the accurate assessment and diagnosis of the disorder, and will allow for refinement of current treatment strategies to ensure treatments effectively target features of the disorder as it presents at different developmental stages. While the cognitive theory of OCD is one of the most widely accepted accounts of the maintenance of the disorder in adults, no study to date has systematically evaluated this theory across children, adolescents and adults with the disorder. Until empirical investigation examines the applicability of this theory to children and adolescents, we know very little about the cognitive processes associated with OCD during childhood or adolescence. The second study investigated developmental differences in the cognitive processing of threat in a sample of children (n = 34), adolescents (n = 39) and adults (n = 38) with OCD. Using an idiographic assessment approach, as well as self-report questionnaires, this study evaluated cognitive appraisals of responsibility, probability, severity, thought-action fusion (TAF), thought-suppression, self-doubt and cognitive control. It was hypothesised that there would be age related differences in reported responsibility for harm, probability of harm, severity of harm, thought suppression, TAF, self-doubt and cognitive control. Results demonstrated that children with OCD reported experiencing fewer intrusive thoughts, which were less distressing and less uncontrollable than those experienced by adolescents and adults with OCD. Furthermore, responsibility attitudes, probability biases and thought suppression strategies were significantly higher in adolescents and adults with OCD, compared to children. Cognitive processes of TAF, perceived severity of harm, self-doubt and cognitive control were found to be comparable across age groups. These findings suggest that some cognitive biases associated with OCD in adults, are in fact also associated with OCD during childhood and adolescence, however there remains some discontinuity across specific cognitive processes. For a developmentally sensitive theory of OCD, further investigation is clearly warranted into other possible age related maintenance factors of this disorder. Implications of these 2 empirical investigations are highlighted and directions for future research are discussed.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Applied Psychology (Health)
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35

Devignes, Quentin. "The dual cognitive syndrome hypothesis in Parkinson’s disease : MRI studies of structural and functional correlates." Thesis, Université de Lille (2018-2021), 2021. https://pepite-depot.univ-lille.fr/ToutIDP/EDBSL/2021/2021LILUS064.pdf.

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La maladie de Parkinson (MP) est une pathologie neurodégénérative caractérisée par des troubles moteurs. Cependant, des symptômes non-moteurs tels que les troubles cognitifs font partie intégrante du tableau clinique de la maladie. Trois grandes présentations cliniques des troubles cognitifs dans la MP peuvent être distinguées : (a) l’absence de troubles significatifs malgré d’éventuels symptômes, (b) les troubles cognitifs légers et (c) la démence de la maladie de Parkinson. Les troubles cognitifs légers renvoient à des déficits cognitifs significatifs en l’absence de déclin cognitif global et d’impact sur les principales activités de la vie quotidienne. Ces troubles, communs dans la maladie de Parkinson, peuvent affecter diverses fonctions cognitives. L’hypothèse du double syndrome suggère l’existence de deux sous-types cognitifs : frontostriatal, caractérisé par des déficits attentionnels et/ou exécutifs, et cortical postérieur, caractérisé par des déficits visuospatiaux, mnésiques et/ou langagiers. Ce dernier a été associé avec un risque accru d’évolution précoce vers la démence. À ce jour, peu d’études ont pris en compte l’hétérogénéité des troubles cognitifs légers observés dans la MP et aucune étude n’a déterminé des sous-types sur la base de l’hypothèse du double syndrome. Par ailleurs, nous manquons de biomarqueurs in-vivo associés à ces sous-types cognitifs.Les objectifs principaux de cette thèse étaient (a) de proposer un état de l’art concernant les résultats en neuroimagerie associés à des sous-types cognitifs distincts de troubles cognitifs légers dans la maladie de Parkinson et (b) d’identifier en IRM des changements structuraux et fonctionnels du cerveau associés aux sous-types frontostriatal et cortical postérieur.Par conséquent, nous avons réalisé une revue systématique qui a montré un manque dans la littérature scientifique étant donné que seules dix études de neuroimagerie considérant des sous-types de troubles cognitifs légers dans la maladie de Parkinson ont été identifiées. Par la suite, nous avons conduit deux études en IRM pour identifier des modifications structurales et fonctionnelles de repos dans des sous-types cognitifs de troubles cognitifs légers. Nous avons utilisé les données issues d’un groupe de patients non-déments présentant une maladie de Parkinson (n=114) dont le sous-type cognitif a été déterminé sur la base de leurs performances à une batterie de tests neuropsychologiques : (a) avec une cognition normale (PD-NC) (n=41), (b) avec un sous-type frontostriatal (PD-FS) (n=16), (c) avec un sous-type cortical postérieur (PD-PC) (n=25) et (d) avec un sous-type mixte (PD-MS), c’est-à-dire une combinaison de déficits frontostriataux et corticaux postérieurs (n=32). Pour les analyses fonctionnelles, des données issues de 24 sujets sains appariés en âge ont également été utilisées.Nos résultats ont montré (a) des altérations structurales plus abondantes et plus étendues chez les patients avec des déficits corticaux postérieurs (PD-PC et PD-MS), (b) une augmentation de la connectivité fonctionnelle au sein des ganglions de la base chez les patients PD-PC et (c) une diminution de la connectivité fonctionnelle dans divers réseaux de repos chez les patients avec des déficits frontostriataux (PD-FS et PD-MS). De futures études longitudinales seront nécessaires pour évaluer la progression de ces modifications structurales et fonctionnelles et pour déterminer le potentiel prédictif de ces marqueurs au regard du risque d’évoluer vers la démence
Parkinson’s disease (PD) is a neurodegenerative disease characterized by motor disorders. However, non-motor symptoms, including cognitive impairment, are also part of the clinical presentation. According to the severity of cognitive impairment, three presentations are usually distinguished in PD: (a) the absence of significant cognitive impairment despite possible symptoms, (b) mild cognitive impairment (MCI) and (c) PD dementia. MCI refers to significant cognitive deficits without global cognitive decline nor impact on activities of daily living. This condition is common in Parkinson’s disease (PD-MCI), can affect one or several cognitive functions and is heterogenous. According to the dual syndrome hypothesis, PD-MCI can be subdivided into two cognitive subtypes: a frontostriatal one, characterized by attentional and/or executive deficits, and a posterior cortical one, characterized by visuospatial, memory and/or language deficits. The latter has been associated with a higher risk of developing dementia earlier. To date, only few studies have considered the cognitive heterogeneity in PD-MCI and no study defined PD-MCI subtypes based on the dual syndrome hypothesis. Besides, in-vivo biomarkers of these cognitive subtypes are lacking.The main objectives of this thesis were (a) to propose a state-of-the-art on neuroimaging outcomes associated with distinct PD-MCI cognitive subtypes, and (b) to identify structural and functional MRI brain changes associated with the frontostriatal and posterior cortical subtypes.Therefore, we performed a systematic review which showed a gap in the scientific literature given that only ten neuroimaging studies considering PD-MCI subtypes were identified. Thereafter, we conducted two studies to identify structural and resting-state functional MRI modifications in PD-MCI subtypes. We used data from non-demented PD patients (n=114) whose cognitive subtype was determined by their cognitive performance at a comprehensive neuropsychological test battery: (a) patients with normal cognition (PD-NC) (n=41), (b) patients with a frontostriatal subtype (PD-FS) (n=16), (c) patients with a posterior cortical subtype (PD-PC) (n=25) and (d) patients with a mixed subtype (PD-MS) (i.e. combination of frontostriatal and posterior cortical deficits) (n=32). For functional analyses, data from 24 age-matched healthy controls were also used.Our results showed (a) more abundant and more extensive structural alterations in patients with posterior cortical deficits (PD-PC and PD-MS), (b) increased functional connectivity within the basal ganglia in PD-PC patients and (c) decreased functional connectivity in various resting-state networks in patients with frontostriatal deficits (PD-FS and PD-MS). Further longitudinal studies are needed to assess the progression of these structural and functional modifications and to determine the predictive potential of these markers regarding the risk of developing dementia

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Muhammad, Rahmat. "The mouse visually evoked potential : neural correlates and functional applications." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/46388.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, 2009.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
"February 2009."
Includes bibliographical references.
The visually evoked potential (VEP) is a local field potential (LFP) evoked in visual cortex in response to visual stimuli. Unlike extracellular single unit recordings, which allow us to probe the function of single spiking cells acutely, the chronic VEP technique gives us insight into ensemble synaptic activity. However, while action potentials are easily interpreted as the output of the recorded neuron, LFPs are difficult to interpret because they may reflect the sum of activity occurring at or beyond the site of recording. The goal of this study was to use the current source density (CSD) method to derive information about synaptic activity occurring at the site of recording and to determine how this activity relates to the concurrent LFP. The mouse has recently become a widely-used experimental model for studying the mechanisms of plasticity and there has been an increase in the use of VEP recordings to study experience-dependent changes in mouse primary visual cortex (V1). These studies typically focus on changes occurring in the layer 4 VEP after a variable period of visual deprivation. Layer 4 of mouse V1 receives heavy direct input from the lateral geniculate nucleus. This initial input is followed by strict hierarchical connectivity from cortical layer 4 to superficial layers 2/3 and from 2/3 to deep layers 5/6. Using a method for silencing cortical activity without affecting geniculate input activity in conjunction with CSD analyses, we found that the laminar flow of activity in mouse V1 in response to various grating stimuli was consistent with the anatomical connectivity going from layer 4 ?? 2/3 ?? 5/6. To determine if the layer 4 VEP is indeed reflecting synaptic activity occurring in layer 4, we applied the CSD method to field potentials recorded from mouse V1. Our results indicate that changes in the layer 4 VEP strongly and significantly covaries with changes in layer 4 current sink activity suggesting that the layer 4 VEP is indeed reflecting local layer 4 synaptic activity.
(cont.) This layer 4 activity is likely due to direct geniculate input since it persisted after intracortical activity was blocked. If the layer 4 VEP reflects synaptic activity due to direct geniculo-cortical input and if this input is carrying information about the visual world then we would expect the VEP to change as the parameters of the stimuli vary. Indeed the binocular-driven VEP broadened in shape as we increased the spatial frequency (SF) of grating stimuli. Using CSD analyses, we were able to trace the transformations of the layer 4 VEP waveform to changes happening in layer 4 current sinks and layer 4 current sinks were in turn affected by events in deep layers. Specifically, increasing SF of the grating stimuli led to a reduction of current sink activity in deep layers and this unmasked prolonged current sink activity in layer 4. This prolonged layer 4 current sink activity persisted after cortical silencing suggesting that it is likely due to late-onset direct geniculate input. We suggest that late-onset activity from the ipsilateral-eye may be unmasked with increasing SF. VEPs have been used extensively in the clinical and laboratory setting to determine visual acuity in humans as well as anaesthetized animals. If the layer 4 VEP is to be a useful measure of visual function in awake head-fixed mice, VEP-assessed visual acuity and contrast sensitivity should be consistent with behaviorally-assessed measures. We found that VEP-assessed visual acuity agreed with previous behaviorally-assessed acuity; however, VEP-assessed contrast-sensitivity values were slightly higher. One of the reasons why inbred laboratory mice are becoming increasingly useful in Neuroscience is because individual mice are genetically identical and any behavioral variability should be experience-driven. While this is true for mice within a given strain, it is not true between strains since strains are genetically different. Therefore, it is crucial to understand how strain differences in genes affects neural activity before comparing results from different strains.
(cont.) To this end, we compared the VEP response of two commonly used laboratory mouse strains: C57BL/6 and 129/Sv and found important differences in the VEP waveform which may translate into differences in visual function. Specifically, our data suggest that 129/Sv mice may have better acuity than C57BL/6 mice. The advent of molecular engineering tools is another reason why the mouse has become the preferred model system for studying the cellular and molecular mechanisms underlying behavioral and physiological phenomena. Genetically modified mice are routinely screened for behavioral deficits using tasks such as the Morris watermaze -- test for spatial navigation which assumes that the mice have functional vision. In order to remove the experimental confound of vision, the layer 4 VEP can be used to assay the visual function of mice prior to behavioral experimentation. Using the VEP technique, we determined the visual function of Shank1-/- mice to be normal in response to low SF gratings but impaired in response to high SF gratings. Shank1-/- mice were not impaired in the eight-arm radial maze task - another test of spatial navigation suggesting that low SF vision may be sufficient for performing this task. Taken together, this study demonstrates that the VEP is an interpretable and useful recording technique which can be combined with CSD analysis to determine the laminar activity patterns which underlie visual function in the awake mouse.
by Rahmat Muhammad.
Ph.D.

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37

Aimola, Lina. "Cognitive and anatomical correlates of neglect for peripersonal and extrapersonal space." Thesis, University of Hull, 2008. http://hydra.hull.ac.uk/resources/hull:5817.

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Spatial neglect is a neurological disorder where patients typically fail to orient or respond to events on their left side. Moreover, recent studies suggest that the severity of neglect may depend specifically on whether stimuli are presented within or beyond arm's reach. However, the evidence for such a general functional dissociation between near and far space processing in the brain remains conflicting: The majority of research has been focussed on line bisection errors which reflect only one small aspect of neglect behaviour. In addition, some behavioural findings suggest a functional dissociation only if a motor response is required. Finally, to date, the critical areas involved in distance related space processing have not been identified. Thus, it remains not only unclear whether neglect in near and far space is a task- and response independent phenomenon but also which damaged brain areas impair distance related space processing. In order to answer these questions the present study compared line bisection and visual search performance and its anatomical correlates in near and far space by using a combined single case- and group study approach. The results showed that neglect restricted to near or far space can vary not only depending on the type of task but also on the type of response required. Visual search tasks were particularly sensitive in detecting the dissociation between those two space sectors. Anatomically, neglect for near space was mainly associated with occipito-parietal lesions and medio-temporal structures, including the posterior cingulate. Neglect for far space was found to result from focal damage of medial, ventro-temporal structures and the prefrontal cortex. In conclusion, neglect for near and far space does not seem to result from a general impairment in distance related processing but from a combination of factors related to specific task demands as well as the location and extent of the brain damage.

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Taroyan, Aira Arseni. "Electrophysiological and behavioural correlates of dyslexia in perceptual and cognitive tasks." Thesis, University of Sheffield, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.489110.

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Despite recent extensive research in the field of dyslexia, the causal links between various behavioural symptoms and underlying neural mechanisms of this developmental disorder proposed by different theories are still hotly debated. In this project I aimed to combine behavioural and neurophysiological tests of global coherent motion (magnocellular), visual word from recognition and lexical decision (phonological), as well as attention deficits in English speaking dyslexic adolescents.

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Ashinoff, Brandon Kay. "The behavioral and neural correlates of cognitive control across the lifespan." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7738/.

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This dissertation will investigate which brain mechanisms are involved in proactive and reactive cognitive control across the lifespan, how the function of those brain mechanisms is affected by age, and how those functional changes translate to differences in behavior. Chapter 1 provides a comprehensive literature review covering proactive and reactive control in an ageing context, the contributions of the left IPS and left TPJ to suppression of salient distractors, and how these two topics may be interrelated. Chapter 2 examined the neural correlates of proactive inhibition in a young and aging cohort, with focus on the contribution of left IPS and/or left TPJ. It was found that while young participants only engaged proactive mechanisms (Left IPS) to engage the task, old participants engaged both proactive (Left IPS) and reactive (Left TPJ) mechanisms simultaneously. Further, age-related reductions in resting state functional connectivity suggested that both proactive and reactive inhibition mechanisms were impaired in aging populations. Chapter 3 assessed if there are detectable behavioral deficits during a reactive inhibition task in old age. Elderly participants showed an impaired ability to reactively use a salient distractor as an anti-cue. Chapter 4 used TMS to explicitly test the role of the left TPJ during reactive control. It was found that applying TMS to the left TPJ impaired participants’ ability to reactively engage a salient distractor as an anti-cue and, surprisingly, that applying TMS to the left IPS enhanced this ability. Chapter 5 tested if the allocation of attention to a distractor prior to inhibition is impaired in aging participants. The result revealed no age-related impairment to attentional control prior to inhibition. Chapter 6 summarizes the findings, discusses their broader implications, and proposes avenues for future research.

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Wadeley, A. "Cognitive correlates of sleepiness and sleep disruption in everyday domestic settings." Thesis, Bath Spa University, 2014. http://researchspace.bathspa.ac.uk/5200/.

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Sleepiness and sleep disruption caused by cohabitees could have deleterious cognitive consequences in everyday life. Research in this area is scarce, thus cognitive correlates of varying degrees of sub-optimal sleep patterns in five groups of healthy adults in domestic settings were studied. The groups studied included adults living with healthy partners, adults living with partners with a chronic, sleep-disrupting illness (Parkinson's disease), and mothers of young children.

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Udiawar, Maneesh. "Cardiometabolic and neuroimaging correlates of cognitive function in polycystic ovary syndrome." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/103000/.

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Background: Polycystic ovary syndrome (PCOS) is a disorder characterized by insulin resistance and hyperandrogenism, which leads to an increased risk of type 2 diabetes in later life. Androgens and insulin signalling affect brain function but little is known about brain structure and function in younger adults with PCOS. Aims and Methods: To establish whether young women with PCOS display altered white matter microstructure and cognitive function. Eighteen individuals with PCOS (age, 31 ± 6 y; body mass index [BMI] 30 ± 6 kg/m2) and 18 control subjects (age, 31 ± 7 y; BMI, 29 ± 6 kg/m2), matched for age, IQ, and BMI, underwent anthropometric and metabolic evaluation, diffusion tensor MRI, a technique especially sensitive to brain white matter structure, and cognitive assessment. Cognitive scores and white matter diffusion metrics were compared between groups. White matter microstructure was evaluated across the whole white matter skeleton using tract-based spatial statistics. Associations with metabolic indices were also evaluated. Results: PCOS was associated with a widespread reduction in axial diffusivity (diffusion along the main axis of white matter fibres) and increased tissue volume fraction (the proportion of volume filled by white or grey matter rather than cerebrospinal fluid) in the corpus callosum. Cognitive performance was reduced compared with controls (first principal component, t = 2.9, P = .007), reflecting subtle decrements across a broad range of cognitive tests, despite similar education and premorbid intelligence. In PCOS, there was a reversal of the relationship seen in controls between brain microstructure and both androgens and insulin resistance.

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Elisens, Merrie M. "The Cognitive and Emotional Correlates of Neglect in School Age Children." Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc278331/.

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The purpose of this study was to examine the cognitive and emotional functioning of neglected, physically abused, and clinical control children between six and thirteen years of age who were referred for testing at the Dallas Child Guidance Clinic.

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Blain, Bastien. "Focused cognitive fatigue and decision making : behavioral evidence and neuroimaging correlates." Thesis, Paris 1, 2016. http://www.theses.fr/2016PA01E059.

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Les préférences temporelles constituent un des champs d'étude privilégiés en économie, car elles reflètent le comportement d'épargne et de consommation des individus. De façon critique, la mesure des préférences temporelles en laboratoire permet de prédire des caractéristiques individuelles, que ce soit en termes de revenu, d'éducation ou de santé. Les résultats accumulés dans le domaine des neurosciences ces dernières années suggèrent que les préférences temporelles dépendent de l'activité et de l'anatomie de régions particulières du cerveau, le cortex préfrontal latéral. Une prédiction non triviale est alors qu'un changement d'activité induit dans ces régions pourrait changer les préférences temporelles. Des études ont montré qu'inhiber artificiellement avec un aimant l'activité cérébrale du cortex préfrontal latéral augmente la préférence pour le présent (ou impulsivité). L'objet de cette thèse est de montrer que des phénomènes du quotidien, en particulier la fatigue, induisent l'inhibition de ces régions, avec pour conséquence d'augmenter l'impulsivité. Ainsi, cette thèse montre qu'effectuer des tâches cognitives difficiles pendant plusieurs heures inhibe l'activité du cortex préfrontal latéral, et augmente l'impulsivité des participants. Le surentraînement physique pendant trois semaines conduit aux mêmes effets comportementaux et neuraux. Réviser des examens conduit au même effet comportemental. D'un point de vue computationnel, cet effet est dû à l'augmentation d'un biais vers le présent, plutôt qu'une augmentation du taux d'escompte temporel, et semble suivre la fatigue subjective. Une hypothèse pour expliquer ce résultat serait l'augmentation du coût de l'utilisation du cortex préfrontal latéral. L'étude de la nature de ce coût, qui n'a pas été menée dans cette thèse, est une perspective qu'elle a néanmoins contribué à dégager : s'agit-il de l'épuisement d'une ressource ? De l'accumulation de déchets métabolites ? La nature de telles substances reste à l'heure actuelle spéculative
Intertemporal preferences are one of the most studied topics in economics, because they adjust the balance between saving and consuming. Critically, lab measures of intertemporal preferences allow to predict individual traits, in terms of income, health and education. Findings in neuroscience during the last decade suggest that intertemporal preferences depend on the activity and integrity of a specific brain area, the lateral prefrontal cortex. Therefore, any change induced in that brain area should affect intertemporal preferences. Some studies have indeed shown that artificially inhibiting the activity of the lateral prefrontal cortex, through transcranial magnetic stimulation, does enhance preference for the present (i.e., impulsivity). The aim of this thesis is to show that daily phenomena in more natural conditions, subjectively perceived as fatigue, reduce lateral prefrontal cortex excitability and exacerbate choice impulsivity. This is shown in three different contexts, corresponding to three separate studies. First, performing hard cognitive tasks for several hours inhibits the lateral prefrontal cortex, explaining the increase in choice impulsivity. Second, rehearsing examinations for several hours enhance choice impulsivity. Third, physical overtraining imposed over two weeks leads to the same fatigue effects at both the behavioral and neural levels. From a computational perspective, the increase in choice impulsivity was best captured by changing the present bias, and not by changing the discount rate. Our interpretation is that the cost of using the lateral prefrontal cortex increases with time on task, generating a subjective feeling of fatigue and reducing its contribution to choices, and hence the control of preference for the present. The nature of this cost is open to discussion: does it correspond to a biological degradation or to a functional adaptation?

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Baker, Maryhan. "The onset of contrastive responding in infants and its cognitive correlates." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440440.

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45

Hamilton, Joanne M. "Cognitive, motor, and behavioral correlates of functional decline in Huntington's disease /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p9975028.

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46

Roos, Annerine. "Psychobiological correlates of distress in pregnancy." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6712.

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Thesis (PhD (Psychiatry))--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: Pregnancy is often accompanied by distressing psychological symptoms such as anxiety. These symptoms may result from changes in cognitive-affective processing, which in turn reflect hormonal changes during this time. However, findings on associations between psychological distress, cognitive-affective changes and hormones have been inconsistent. Furthermore, few studies have investigated the neural circuitry underlying distress and cognitive-affective processing in pregnancy. The prefrontal cortex (PFC) plays a specific role in regulating emotion. Determining the relationship between these changes in cognitive-affective processing and in prefrontal circuitry is important, given the high prevalence of depressive and anxiety disorders in pregnancy. The overall objective of this study was to investigate distressing psychological symptoms and their association with cognitive-affective processes and neurobiological changes over the course of pregnancy. Pregnant women with low risk singleton pregnancies were recruited from Midwife Obstetric Units in the Western Cape. Non-pregnant healthy controls were also recruited from the same demographic area. Distress levels were assessed using the K-10, Spielberger State -Trait Inventory, and Perceived Stress Scale. Subjectively experienced cognitive ability was asked about. Objective cognitive ability was assessed using standardized neuropsychological tests. Selective attention to threat such as fear and anger was assessed using a Facial Stroop Task. Neural circuitry was assessed using Near-Infrared Spectroscopy while viewing dynamic emotional facial expressions of threat (Emotion Recognition Task). Glucocorticoid (cortisol) and gonadal hormonal levels (estrogen, progesterone, and testosterone) were also determined at each trimester of pregnancy. Associations between distressing psychological symptoms, cognitive-affective processes and neurobiology were assessed using standard statistical methods. The main findings to emerge from this research were that, 1. pregnant women had significantly higher trait anxiety at trimester 2, compared to trimester 1 of pregnancy; 2. compared to non-pregnant women, pregnant women paid significantly more attention to fearful faces across trimesters, suggesting altered cognitive-affective processing in pregnancy compared to non-pregnancy; 3. pregnant women demonstrated significantly increased PFC activation in response to fearful and angry faces (all trimesters) that was particularly evident at trimester 2; 4. the PFC activation was, across trimesters, significantly correlated with distress and selective attention to threat; and 5. the PFC activation was, across trimesters, also significantly associated with increased glucocorticoid and gonadal hormone levels. The main findings of this study are consistent with previous literature insofar as distress has previously been associated with altered cognitive-affective processing and prefrontal cortex activation, but extend it by showing that emotional regulation is altered in pregnancy compared to the non-pregnant state. These data provide an important insight into distressing psychological symptoms and their associations with cognitive-affective processes, and changes in neural circuitry and in hormone levels in pregnancy. These findings are also the first to show that structures involved in emotional processing (e.g. the PFC) also play a role in the regulation of affect in pregnancy. Future research should explore the causal mechanisms underlying altered emotional regulation in pregnancy, and include pregnant women that are clinically depressed or anxious as comparison subjects.
AFRIKAANSE OPSOMMING: Swangerskap word dikwels geassosieër met stres-veroorsakende sielkundige simptome soos angstigheid. Hierdie simptome mag die gevolg wees van veranderinge in kognitief-affektiewe prosessering, wat op sy beurt mag dui op hormonale veranderinge. Bevindinge oor assosiasies tussen sielkundige stres, kognitief-affektiewe prosessering en hormone is tot dusver onbeslis. Voorts was min studies gerig op die neurologiese meganika onderliggend aan stres en kognitief-affektiewe prosessering tydens swangerskap. Die prefrontale korteks (PFK) het 'n spesifieke rol in die regulering van emosie. Die bepaling van spesifieke assosiasies tussen veranderinge in kognitief-affektiewe prosessering en in prefrontale regulering is belangrik, gegewe die hoë voorkoms van toestande soos depressie en angssteurings tydens swangerskap. Die doel met hierdie studie was 'n ondersoek na assosiasies tussen stres-veroorsakende sielkundige simptome, kognitief-affektiewe prosesse en neurobiologie tydens swangerskap. Swanger vroue met lae risiko enkel-swangerskappe is gewerf by klinieke in Wes-Kaapland. Gesonde nie-swanger vroue is uit dieselfde omgewing gewerf as kontroles. Angs-vlakke is geevalueer met behulp van die K-10; die Spielberger State-Trait Inventory en die Perceived Stress Scale. Vrae is tydens ondersoeke gevra oor subjektief-ervaarde kognitiewe vermoë. Voorts is kognitiewe vermoë geëvalueer met behulp van gestandardiseerde neurosielkundige toetse. Hierbenewens is selektiewe aandag aan bedreigende gesigte wat vrees en woede toon, geëvalueer met behulp van 'n Facial Stroop Task. Neurologiese funksie is geëvalueer met gebruik van Na-Infrarooi Spektroskopie terwyl dinamiese bedreigende emosionele gesigsuitdrukkings vertoon is (Emotion Recognition Task). Gluko-kortikoïed (kortisol) en geslagshormoonvlakke (estrogeen, progesteroon, en testosteroon) is gemeet tydens elke trimester. Verwantskappe tussen stresvolle simptome, kognitief-affektiewe prosessering en neurobiologie is geëvalueer met standaard statistiese metodes. Die hoofbevindinge het op die volgende gedui: 1. swanger vroue het betekenisvolle hoër trait angs-vlakke getoon in trimester 2, vergeleke met trimester 1; 2. vergeleke met nie-swanger vroue, het swanger vroue beduidend meer aandag geskenk aan angstige gesigsuitdrukkings tydens elke trimester wat mag dui op veranderde kognitief-affektiewe prosessering tydens swangerskap vergeleke met nie-swangerskap; 3. swanger vroue het beduidend hoër PFK aktivering getoon teenoor angstige en kwaai gesigte in alle trimesters, maar veral in trimester 2; 4. swanger vroue se PFK aktivering het, in alle trimesters, beduidend gekorreleer het met stres-vlakke en selektiewe aandag teenoor bedreigende stimuli; en 5. swanger vroue se PFK aktivering het, in alle trimesters, ook 'n beduidende verwantskap getoon met verhoogde gluko-kortikoïed en geslagshormoonvlakke. Die hoofbevindinge in hierdie studie stem ooreen met vorige literatuur wat aangedui het dat daar 'n verband is tussen stres en veranderinge in kognitief-affektiewe prosessering en in prefrontale korteks aktivering, maar dui verder op veranderinge in emosionele regulering tydens swangerskap vergeleke met nie-swangerskap. Die data bied 'n belangrike insig in stres-veroorsakende sielkundige simptome; hul verwantskap met kognitief-affektiewe prosesse; veranderinge in neurologiese netwerke; en veranderinge in hormoonvlakke tydens swangerskap. Sover bekend is dit ook die eerste keer bevind dat strukture wat betrokke is by emosionele prosessering (bv. die PFK), ook betrokke is in die regulering van emosie tydens swangerskap. Dit is belangrik dat toekomstige navorsing die onderliggende meganismes wat veranderinge in emosionele regulering teweeg bring, ondersoek. Verdere ondersoek om hierdie veranderinge in swanger depressie-lyers of diegene met angssteurings te vergelyk is ook van belang.

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47

Heitz, Richard P. "Neural correlates of speed-accuracy tradeoff an electrophysiological analysis /." Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-03282007-110854/.

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Thesis (Ph. D.)--Psychology, Georgia Institute of Technology, 2007.
Washburn, David, Committee Member ; Spieler, Dan, Committee Member ; Schumacher, Eric, Committee Member ; Engle, Randall, Committee Chair ; Corballis, Paul, Committee Member.

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48

Wade, Emma, and emma wade@rch org au. "Resilient Victims of School Bullying: Psychosocial Correlates of Positive Outcomes." RMIT University. Health Sciences, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080603.101203.

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Bullying is a phenomenon that has serious psychological consequences for victims, including low psychological wellbeing, poor social adjustment, psychological distress, and physical illness. Bullying has become a topic of increasing public concern and the focus of considerable research in Australia over the last decade. Parallel to this rise in interest in bullying research is a rise in research into resilience. Research has indicated that children facing distress will show a range of responses; some will regress, while others tolerate and even thrive in the face of trauma; it is this second group that are described as resilient. It was therefore postulated in this thesis that individuals exposed to bullying may not all succumb to the typical negative effects of being a victim of school bullying. While previous studies have noted the difference in reactions to bullying, this is the first study to investigate whether resilient victims can be identified, and their key psychosocial characteristics profiled. Based on this notion, it was predicted that victims of bullying could be taught a set of skills and attitudes that would build their resilience to the expected effects of bullying. The present research consisted of two studies. Study 1 had two phases. The first phase of Study 1 identified 'resilient victims' of school bullying by assessing participants on their levels of victimisation and their levels of wellbeing using a battery of questionnaires. Participants were assigned to one of four groups: resilient victims, non-resilient victims, healthy non-victims, or poor-health non-victims. From the original sample of 867 students, 111 were categorised into one of the four groups, and completed a second questionnaire package. The second phase examined the relationships between these resilience groups and eight psychosocial correlates of general resilience: individual protective factors, optimism, coping, social support, social skills, self-esteem, self-concept, and emotional intelligence. The results showed that there were significant discriminators between resilient and non-resilient victims, particularly on factors such as optimism, productive coping, self-concept and self-esteem, and so cial variables. The aims of the second study were to 1) develop a cognitive-behavioural group intervention program to teach social skills, perceived social support, self-esteem, optimism, and effective coping skills, to adolescent victims of school bullying; and 2) to investigate the effectiveness of the intervention. Ten year 7 and 8 students who reported negative consequences to high levels of bullying participated in the intervention program. Results indicated that the program had positive effects on the skills and attitudes that the program targeted. The program also appeared to have positive effects on the participants' levels of victimisation and general wellbeing.

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49

O'Kane, Gail 1965. "Cognitive and neural correlates of memory retrieval in young and older adults." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28852.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, 2004.
Also issued in leaves.
Includes bibliographical references.
(cont.) increased activity whenever recollection was attempted, independent of the level of recollection success. The results are consistent with the hypothesis that increased left-lateralized retrieval activity in older adults supports recollection attempt. Age deficits in semantic memory are more subtle than in episodic memory. However, older adults are impaired when automatic, data-driven processes are not sufficient to support the retrieval of conceptual knowledge. The fMRI study described in Chapter 3 used semantic repetition priming to test two theories of the role LIPC plays in semantic retrieval. Young adults exhibited repetition-related BOLD response reductions in LIPC that were specific to the particular semantic task engaged, consistent with the hypothesis that LIPC supports controlled semantic retrieval. Older adults, in contrast, exhibited repetition-related signal reductions even when the semantic judgment made about a word differed across the two exposures, consistent with the hypothesis that older adults fail to gate irrelevant semantic information from working memory during initial presentation of the word.
Older adults are impaired in episodic and semantic retrieval but the extent of these deficits and their neural correlates is unknown. In episodic memory, older adults appear particularly impaired in retrieving bound information, such as conjunctions of items or of an item and its context. These retrieval deficits, however, may be merely the downstream effects of poor encoding. Chapter 1 presents a series of studies that test the theory that age-related recollection deficits are due to encoding failures. Results revealed that older adults were impaired in associative recognition when self-initiated processes were required at acquisition. Additional encoding support eliminated age differences, however, even when the retrieval task was made more difficult. The results support the hypothesis that recollection deficits are primarily due to poor encoding. Although older adults with encoding support can retrieve information as well as young adults, it is an open question whether brain activity supporting retrieval is identical in the two groups. In past studies, greater left prefrontal activity has been observed in older adults even when their performance does not differ from young adults. However, the circumstances under which this pattern arises and its functional significance are still unknown. Chapter 2 presents a functional magnetic resonance imaging (fMRI) study of associative recognition by young and older adults who performed equally well but who showed different patterns of recollection-related activity. Young adults exhibited greater activity in left inferior prefrontal cortex (LIPC) and inferior temporal/fusiform gyri for retrieval based on recollection relative to retrieval based on familiarity. In the same regions, older adults exhibit
by Gail O'Kane.
Ph.D.

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50

Kornblith, Simon (Simon John). "Spiking and oscillatory correlates of visual short-term memory for multiple items." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113953.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 119-132).
The richness of visual experience far exceeds our ability to remember what we have seen. However, it is unclear what neural mechanisms give rise to these limits to visual short-term memory capacity. Here, we measured neural activity in a change localization task, in which monkeys viewed two displays of multiple colored squares separated by a brief delay, and made a saccade to the square that changed color between displays. In chapter 2, we examine local field potentials in the lateral intraparietal area (LIP), frontal eye field, and lateral prefrontal cortex (PFC). At stimulus encoding, lower frequency oscillations decreased in power in proportion to the total number of stimuli presented, while higher frequency oscillations increased in power in proportion to the number of stimuli contralateral to the recording site. During the delay, lower frequency power instead increased with the number of contralateral stimuli, while higher frequency power was not modulated. We interpret these findings in terms of roles for low- and high-frequency oscillations in changing and maintaining cognitive state. In chapter 3, we compare spiking activity between LIP, PFC, and inferotemporal cortex (IT). Although the task required that the animal remember stimulus colors, activity in LIP and PFC primarily reflected the stimulus positions, while activity in IT primarily reflected color. In PFC, color information increased with the number of stimuli presented, while in IT, color information remained constant or decreased. Thus, IT was more strongly capacity-limited than PFC. Color selectivity during the delay was weak in all regions. However, in IT, activity at test stimulus presentation reflected the difference in square colors between the sample and test displays, while in PFC, activity primarily reflected the location of the changed square. Selectivity to these attributes was stronger on correct trials than incorrect trials. Our findings suggest a possible role for passive processes in IT in visual short-term memory.
by Simon Kornblith.
Ph. D.

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Dissertations / Theses on the topic 'Cognitive correlates'

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