Thèses : « Neural correlate »

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Miyata, Jun. « Reduced white matter integrity as a neural correlate of social cognition deficits in schizophrenia ». Kyoto University, 2011. http://hdl.handle.net/2433/135382.

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Sorella, Sara. « The psychological and neural mechanisms of anger and its regulation ». Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/328507.

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The ability to experience, use, and eventually control anger is crucial for maintaining well-being, achieving our goals, and building healthy relationships. Despite its relevance, the neural and psychological mechanisms behind this emotion are still in their early stages. Therefore, the present work represents an effort towards the investigation of these features of anger, where the ambition is to take a step forward to bridge the gaps between the research and clinical fields. Chapter 1 will expose an introduction on anger, while Chapter 2 will expose the evidence in literature on the neural bases of anger relying on a meta-analytic approach, where the neural bases of anger perception and anger experience will be investigated. Chapter 3 relies on a multivariate data-driven approach in order to study the neural networks of anger-related individual differences, identifying a structural network associated with trait anger and a functional network associated with anger control. Chapter 4 focuses on the neural bases of other anger-related individual differences, relying on functional connectivity analysis to investigate the frontal asymmetry hypothesis, finding an association of a left pattern of connectivity with anger externalization and a right pattern of connectivity with anger internalization. Finally, the following two chapters focused on the regulation of anger, in particular considering two different strategies, reappraisal versus suppression, and the related effect of a mindfulness course on the regulation of anger. The final chapter will summarize the evidence provided in this thesis in order to integrate the different results.

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BACCOLO, ELISA. « It’s written all over your face. The ontogeny of sensitivity to facial cues to trustworthiness ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2020. http://hdl.handle.net/10281/277385.

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Gli esseri umani sono ipersensibili a quelle proprietà facciali che trasmettono segnali sociali. La capacità di attribuire giudizi di affidabilità basati sui segnali del volto, vale a dire quei segnali che usiamo per dedurre se una persona può essere avvicinata in modo sicuro o piuttosto evitata, è nota per essere veloce, automatica e basata su pochissime informazioni. Questa tesi di dottorato mira a indagare: (1) se la sensibilità ai tratti di affidabilità del volto sia modulata da differenze individuali nelle attitudini sociali e comportamentali; (2) la traiettoria evolutiva di questa sensibilità; (3) se la sensibilità alle sottili variazioni degli indizi facciali all'affidabilità è un fenomeno universale o è piuttosto modulata dalla cultura e / o dall'etnia del viso. Il Capitolo 1 mira a indagare se differenze nella sensibilità percettiva e nella rappresentazione mentale di volti che variano per livello di affidabilità espressa sono associate a differenze individuali relative alla motivazione sociale. I risultati hanno mostrato che le differenze individuali nella motivazione sociale possono avere un impatto sulla quantità di esperienza sociale e quindi sul livello di sensibilità nei confronti di segnali facciali all'affidabilità. Il capitolo 2 si è concentrato sulla traiettoria evolutiva di tale sensibilità. Lo studio 2 mira a studiare in che modo la sensibilità percettiva e la rappresentazione mentale di differenze minime nell'informazione facciale che sottende la percezione di affidabilità si sviluppano nel tempo, tenendo conto delle differenze individuali nello sviluppo emotivo. I risultati hanno mostrato che la sensibilità ai segnali di affidabilità del volto e la capacità di impiegare questi segnali per generare giudizi di affidabilità è presente in età prescolare, ma matura per raggiungere livelli simili a quelli degli adulti all'età di 7 anni, sviluppandosi insieme alle capacità di comprensione delle emozioni. Gli studi 3 e 4 hanno utilizzato due diversi paradigmi EEG con neonati di 6 mesi per indagare se questa sensibilità sia già presente nel primo anno di vita. I dati combinati provenienti dagli studi 3 e 4 contribuiscono a dimostrare che i bambini di 6 mesi sono sensibili a quegli indizi facciali che vengono successivamente utilizzati per generare giudizi di affidabilità. Infine, il capitolo 3 presenta una convalida di stimoli che verranno utilizzati per esplorare la presenza di differenze cross-culturali nello sviluppo nella percezione dell'affidabilità del volto. Nel complesso, tutti gli studi presentati suggeriscono che la sensibilità ai tratti di affidabilità del volto si manifesta nei primissimi anni di vita, per poi affinarsi tramite l'esperienza nel corso dello sviluppo. Inoltre, suggeriscono che la percezione dell’affidabilità di un volto potrebbe essere cross-culturale, in quanto non è influenzata dall'esperienza che un individuo acquisisce con una determinata categoria di volti.
Human beings are hypersensitive to those facial properties that convey social signals. The ability to attribute trustworthiness judgements based on facial cues to trustworthiness, i.e. those cues that we use to derive whether a person can be safely approached or better avoided, is known to be fast, automatic and based on very little information. This doctoral dissertation aims at investigating: (1) whether sensitivity to facial cues to trustworthiness is modulated by individual variations in social personality characteristics; (2) the developmental trajectory of this sensitivity; (3) if sensitivity to subtle variations in facial cues to trustworthiness is a universal phenomenon or is it modulated by culture and/or face ethnicity. Chapter 1 aimed at investigating whether individual differences in fine-grained perceptual sensitivity and mental representation of facial features related to trustworthiness judgements are associated with individual differences in social motivation. Results showed that individual differences in social motivation can have an impact on the amount of social experience and thus the level of developed sensitivity to facial cues to trustworthiness. Chapter 2 focused on the developmental trajectory of such sensitivity. Study 2 aimed to investigate how perceptual sensitivity to and mental representation of fine-grained differences in facial information subtending social perception of trustworthiness develops in time, taking into account individual differences in emotional development. Results showed that sensitivity to facial cues to trustworthiness and the ability to employ these cues to generate trustworthiness judgements is present in preschool years, but matures to reach adult-like levels at the age of 7, developing together with emotion understanding abilities. Study 3 and 4 used two different EEG paradigms with 6-month-old infants to question whether this sensitivity is already present in the first year of life. Combined data coming from Study 3 and 4 contribute in showing that 6-month-old infants are sensitive to those facial cues that are later used to generate trustworthiness judgements. Finally, Chapter 3 presents a validation of stimuli that will be used to explore the presence of developmental cross-cultural differences in the perception of face trustworthiness. Overall, all presented studies suggest that sensitivity to facial cues to trustworthiness manifests in the very first years of life, to be then refined by experience over the course of development. Moreover, they suggest that trustworthiness perception could be cross-cultural, as it is not influenced by the experience an individual gains with a certain face category.

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Zaugg, Kelsey K. « Do Shape and Volume of Subcortical Neural Structures Involved in Reward Processing Correlate with Body Mass and Food Reward in Adolescent Females ? » BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/9023.

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Background: The prevalence of adolescent obesity has increased drastically in the last few decades, spurring research examining causes and consequences of this chronic health condition. Neuroimaging techniques are being used to determine possible neural correlates of obesity that could help inform research in this field. However, the research among adolescents is not as abundant and findings so far are contradictory. This study sought to examine the association of the shape and volume of subcortical brain structures involved in reward processing with weight status in adolescent females. Additionally, this study sought to determine if the shape and volume of these structures were correlated with the Power of Food Scale (PFS), a self-report measure of food reward sensitivity. Method: The shape and volume of the nucleus accumbens (NAc) and amygdala were examined in 89 adolescent females ranging from normal weight to obese. MR scans were acquired using a high-resolution T1-weighted (MPRAGE) sequence. Shape was estimated using Large Deformation Diffeomorphic Metric Mapping. Seemingly unrelated regression models (SUM) were used for both brain structures with shape and volume as outcome variables and zBMI as the predictor variable. Pairwise correlation coefficients were determined for PFS score and both regions of interest (ROI). Results: SUM results revealed that zBMI was significantly associated with the shape of the left amygdala (β = -1.1, p<.021, 95% confidence interval [CI] = -2.02, -.16). When we controlled for age on the relationship between zBMI and left amygdala shape, we found the following partial correlation: r = -.24, p = .03. The PFS was found to have weak correlations with the volume and shape of the right NAc that approached significance (r = .20, p = .06; r = .19, p = .08, respectively). Conclusions: Our study suggests that there is an association between higher zBMI and aberrations in the shape of the left amygdala. We did not find associations between zBMI and the shape of our other reward-related ROIs, nor did we find any associations with zBMI and ROI volume. These findings suggest that variation in the shape of certain ROIs implicated in reward processing is associated with weight status in adolescents. Our findings also suggest that the shape and volume of the NAc could be a neural correlate of the PFS warranting further investigation. These findings may elucidate an important neural link between weight status and reward processing that could help to inform obesity research in adolescents.

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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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Gisselgård, Jens. « Neural correlates of irrelevant speech / ». Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-857-6/.

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Ruiter, Michiel Benjamin de. « Neural correlates of nonclinical dissociation ». [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2005. http://dare.uva.nl/document/79270.

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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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Mayer, Katja Martina. « Neural correlates of dynamic object recognition ». Thesis, University of Newcastle Upon Tyne, 2011. http://hdl.handle.net/10443/1114.

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This thesis investigates how colourful dynamic objects are represented in the human brain. The two main theories of object recognition (structural description models and image-based models) make different predictions about which object features (e.g., shape, motion, and colour) are critical for recognition and how individual features can be selectively attended for further processing. To investigate the relevance of different features for object recognition two sets of novel 3D objects which had different combinations of shape, colour, and motion were created. Selective attention paradigms in which participants attended to single object features were used. The effects of changing unattended features on behavioural performance (Experiment 1 to 3) and large-scale brain responses (Experiments 4 and 5) were measured. The experiments in this thesis used psychophysical experiments combined with functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI). In addition, the relevance of structural and functional connections between brain areas involved in object recognition was investigated. The results showed that the representations of shape and motion are closely linked while colour seemed to be processed more independently of other features. At the neural level, shape and motion activated a common network consisting of occipitotemporal, lateral-frontal, and parietal areas whereas colour activated ventral occipital areas. Further support for a common network involved in shape and motion processing was found in structural connections between these areas. For example, the integrity of white matter tracts connecting the occipito-temporal and the lateral frontal areas was correlated with behavioural performance. Although colour activated a distinct set of brain areas compared to shape and motion, activity in colour sensitive brain areas modulated the activity in shape sensitive areas which suggests integration processes of multiple object features. The results of this thesis suggest a synthesis of elements of both of the two main object recognition theories rather than favouring one of them.

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Bracci, Stefania. « Neural correlates of hand-tool interaction ». Thesis, Northumbria University, 2011. http://nrl.northumbria.ac.uk/4453/.

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Background: The recent advent of non-invasive functional magnetic resonance image (fMRI) has helped us understand how visual information is processed in the visual system, and the functional organising principles of high-order visual areas beyond striate cortex. In particular, evidence has been reported for a constellation of high-order visual areas that are highly specialised for the visual processing of different object domains such as faces, bodies, and tools. A number of accounts of the underlying principle of functional specialisation in high-order visual cortex propose that visual properties and object domain drive the category selectivity of these areas. However, recent evidence has challenged such accounts, showing that non-visual object properties and connectivity constraints between specialised brain networks can, in part, account for the visual system’s functional organisation. Methodology: Here I will use fMRI to examine how areas along the visual ventral stream and dorsal action stream process visually presented hands and tools. These categories are visually dissimilar but share similar functions. By using different statistical analyses, such as univariate group and single-subject region of interest (ROI) analyses, multivariate multivoxel pattern analyses, and functional connectivity analyses, I will investigate the topics of category-selectivity and the principles underlying the organisation of high-order visual areas in left occipitotemporal and left parietal cortex. Principle Findings: In the first part of this thesis I report novel evidence that, similar to socially relevant faces and bodies, the human high-order visual areas in left occipitotemporal and left parietal cortex houses areas that are selective for the visual processing of human hands. In the second part of this thesis, I show that the visual representation of hands and tools in these areas show large anatomical overlap and high similarity in the response patterns to these categories. As hands and tools differ in visual appearance and object domain yet share action-related properties, the results demonstrate that these category-selective responses in the visual system reflect responses to non-visual action-related object properties common to hands and tools rather than to purely visual properties or object domain. This proposition is further supported by evidence of selective functional connectivity patterns between hand/tool occipitotemporal and parietal areas. Conclusions/Significance: Overall these results indicate that high-order visual cortex is functionally organised to process both visual properties and non-visual object dimensions (e.g., action-related properties). I propose that this correspondence between hand and tool representations in ventral ‘visual’ and parietal ‘action’ areas is constrained by the necessity to connect visual object information to functionally-specific downstream networks (e.g., frontoparietal action network) to facilitate hand-tool action-related processing.

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Quadflieg, Susanne. « The Neural Correlates Of Social Stereotyping ». Thesis, University of Aberdeen, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521349.

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Judging people on the basis of cultural stereotypes is a ubiquitous facet of daily life, yet little is known about how this fundamental inferential strategy is implemented in the brain. In the current thesis, this important issue was addressed across a series of three functional magnetic resonance imaging experiments in the context of gender stereotyping. In Experiment 1, participants read short descriptions of everyday and leisure activities (e.g., play poker) and decided whether these activities were preferentially done by men, women, or equally likely to be undertaken by both sexes. In Experiment 2, participants judged whether a series of gender-stereotypic and non-stereotypic words (e.g., bubbly) could ever be descriptive of a preceding target person. In Experiment 3, participants categorised target individuals who were displayed in gender-congruent or incongruent occupational roles according to sex (e.g. a male vs. a female sailor). By analysing participants’ neural response during these tasks it was found that the neural substrates involved in stereotyping differed depending on what kind of stereotype content was probed (e.g., items of apparel, activities, traits). It was also observed that the neural signature of stereotyping differentiated between target individuals depending on whether they were deemed less or more typical of their respective category. Further analyses revealed that violations of stereotypic expectations impeded the efficiency of core person perception areas to form a coherent person percept. These findings begin to elucidate how stereotyping fits within the neuroscience of person perception and understanding. Whether interindividual differences in gender attitudes can modify the neural correlates of stereotyping, however, remains an issue of debate due to unequivocal findings in the current set of experiments.

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Gupta, Anoopam S. « Behavioral Correlates of Hippocampal Neural Sequences ». Research Showcase @ CMU, 2011. http://repository.cmu.edu/dissertations/206.

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Sequences of neural activity representing paths in an environment are expressed in the rodent hippocampus at three distinct time scales, with different hypothesized roles in hippocampal function. As an animal moves through an environment and passes through a series of place fields, place cells activate and deactivate in sequence, at the time scale of the animal’s movement (i.e., the behavioral time scale). Moreover, at each moment in time, as the animal’s location in the environment overlaps with the firing fields of many place cells, the active place cells fire in sequence during each cycle of the 4-12 Hz theta oscillation observed in the hippocampal local field potentials (i.e., the theta time scale), such that the neural activity, in general, represents a short path that begins slightly behind the animal and ends slightly ahead of the animal. These sequences have been hypothesized to play a role in the encoding and recall of episodes of behavior. Sequences of neural activity occurring at the third time scale are observed during both sleep and awake but restful states, when animals are paused and generally inattentive, and are associated with sharp wave ripple complexes (SWRs) observed in the hippocampal local field potentials. During the awake state, these sequences have been shown to begin near the animal’s location and extend forward (forward replay) or backward (backward replay), and have been hypothesized to play a role in memory consolidation, path planning, and reinforcement learning. This thesis uses a novel sequence detection method and a novel behavioral spatial decision task to study the functional significance of theta sequences and SWR sequences. The premise of the thesis is that by investigating the behavioral content represented by these sequences, we may further our understanding of how these sequences contribute to hippocampal function. The first part of the thesis presents an analysis of SWR sequences or replays, revealing several novel properties of these sequences. In particular it was found that instead of preferentially representing the more recently experienced parts of the maze, as might be expected for memory consolidation, paths that were not recently experienced were more likely to be replayed. Additionally, paths that were never experienced, including shortcut paths, were observed. These observations suggest that hippocampal replay may play a role in constructing and maintaining a "cognitive map" of the environment. The second part of the thesis investigates the properties of theta sequences. A recent study found that theta sequences extend further forward at choice points on a maze and suggested that these sequences may be partly under cognitive control. In this part of the thesis I present an analysis of theta sequences showing that there is diversity in theta sequences, with some sequences extending more forward and others beginning further backward. Furthermore, certain components of the environment are preferentially represented by theta sequences, suggesting that theta sequences may reflect the cognitive "chunking" of the animal’s environment. The third part of the thesis describes a computational model of the hippocampus which explores how synaptic learning due to neural activity during navigation (i.e., theta sequences) may enable the hippocampal network to produce forward, backward, and shortcut sequences during awake rest states (i.e., SWR sequences).

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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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Berger, Joel I. « Behavioural and neural correlates of tinnitus ». Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14315/.

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Tinnitus, often defined as the perception of sound in the absence of an external stimulus, affects millions of people worldwide and, in extreme cases, can be severely debilitating. While certain changes within the auditory system have been linked to tinnitus, the exact underlying causes of the phenomenon have not, as yet, been elucidated. Animal models of tinnitus have considerably furthered understanding of the some of the changes associated with the condition, allowing researchers to examine changes following noise exposure, the most common trigger for tinnitus. This thesis documents the development of an animal model of tinnitus, using the guinea pig to examine neural changes following induction of tinnitus. In the first study, a novel adaptation of a behavioural test was developed, in order to be able to determine whether guinea pigs were experiencing tinnitus following the administration of sodium salicylate, a common inducer of tinnitus in humans. This test relies on a phenomenon known as prepulse inhibition, whereby a startle response can be reduced in amplitude by placing a gap in a low-level, continuous background noise immediately prior to the startling stimulus. The hypothesis for this test is that if the background sound is adjusted to be similar to an animal’s tinnitus (induced artificially following noise exposure or drug administration), the tinnitus percept will fill in the gap and the startle response will not be reduced. The results from this first study indicated that using the Preyer reflex (a flexion of the pinnae in response to a startling stimulus) as this startle measure was more robust in guinea pigs than the commonly-used whole-body startle. Furthermore, transient tinnitus was reliably identified following salicylate administration. Following the development and validation of this test, a study was conducted to determine whether guinea pigs experienced tinnitus following unilateral noise exposure. Neural changes commonly associated with the condition (increases in spontaneous firing rates and changes in auditory brainstem responses) were examined, to determine whether there were any differences between animals that did develop tinnitus following noise exposure and those that did not. Two different methods were applied to the behavioural data to determine which animals were experiencing tinnitus. Regardless of the behavioural criteria used, increased spontaneous firing rates were observed in the inferior colliculus of noise-exposed guinea pigs, in comparison to control animals, but there were no differences between tinnitus and no-tinnitus animals. Conversely, significant reductions in the latency of components of the auditory brainstem response were present only in the tinnitus animals. The final study examined whether the original hypothesis for the behavioural test (that tinnitus is filling in the gap) was valid, or whether there was an alternative explanation for the deficits in behavioural gap detection observed previously, such as changes in the temporal acuity of the auditory system preventing detection of the gap. Recordings were made in the inferior colliculus of noise-exposed animals, separated into tinnitus and no-tinnitus groups according to the behavioural test, as well as unexposed control animals, to determine whether there were changes in the responses of single-units in detecting gaps of varying duration embedded in background noise. While some minor changes were present in no-tinnitus animals, tinnitus animals showed no significant changes in neural gap detection thresholds, demonstrating that changes in temporal acuity cannot account for behavioural gap detection deficits observed following noise exposure. Interestingly, significant shifts in the response types of cells were observed which did appear to relate to tinnitus. The present data indicate that the Preyer reflex gap detection test is appropriate for examining tinnitus in guinea pigs. It also suggests that increases in spontaneous firing rates at the level of the inferior colliculus cannot solely account for tinnitus. Changes in auditory brainstem responses, as well as shifts in response types, do appear to relate to tinnitus and warrant further investigation.

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Wang, Fang. « Neural Correlates of Temporal Context Processing ». Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/83540.

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Temporal context memory is a type of episodic memory that refers to memory for the timing of events. Temporal context includes environmental cues that provide information about the time point at which an event happened. The purpose of the present studies is to investigate the brain mechanisms underlying temporal context processing by using both fMRI and ERP techniques. The fMRI study investigated whether hippocampal representations in CA1 and DG/CA3 subfields were sensitive to the flow of physical time, and if so, whether the number of events that occur during a time period influences the temporal representation of a target event. Results showed that both CA1 and DG/CA3 were sensitive to the flow of physical time, which was indicated by higher representational similarity between two pictures that occurred closer in time than those that occurred more distant in time. However, the variety of preceding events did not influence temporal representation, which was demonstrated by the lack of a significant representational similarity difference between two pictures that were interleaved with variable events as opposed to similar events. The ERP study compared the ERP correlates of temporal to spatial context. Results showed that temporal and spatial contexts had overlapping ERP effects except that the ERP effects of temporal context were more frontally distributed than spatial context. Both the fMRI and ERP studies indicate that temporal context is associated with similar neural correlates to other types of context in episodic memory.
Ph. D.

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Wang, Fang. « Neural correlates of temporal context retrieval ». Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/78100.

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Temporal context memory is memory for the timing of events. People can make temporal judgments based on strategies such as assessing the relative familiarity of events or inferring temporal order from the semantic associations among events. The purpose of present study is to investigate the brain regions that support temporal context retrieval in the absence of such non-temporal strategies (i.e. pure temporal context memory). We used three word familiar phrases (triplets) as stimuli. In study phase, three words were presented quickly one after another in either familiar or scrambled order. Participants were instructed to read aloud each word and try to remember the order of the words. Then they were tested on their memory for the order of the words in each triplet. We propose that memory for the scrambled triplets reflects primarily temporal retrieval for two reasons. First, participants were prevented from using semantic strategies during encoding. Second, the relative familiarity of the words in each triplet was similar and not diagnostic of the order of the words during encoding. Neuroimaging results indicate that temporal context retrieval, memory for the order of words in scrambled triplets, was associated with the hippocampus, parahippocampal cortex, ventromedial prefrontal cortex, retrosplenial cortex, and posterior cingulate, which are consistent with the retrieval of non-temporal context in episodic memory. The results also suggest that temporal context retrieval could rely on familiarity, which was demonstrated by the higher accuracy and greater activation of PRc in familiar phrases and scrambled triplets presented in studied order in the test phase.
Master of Science

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Hasttyar, Hamshin Darun. « Moral emotions and their neural correlates ». Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-19173.

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This thesis aims to investigate and present what the most recent research can disclose about moral emotions and their neural correlates. This literature review provides an overview of some frameworks and theories regarding moral emotions and their neural correlates, with a specific focus on positive and negative moral emotions such as compassion, pride, gratitude, guilt, shame, and embarrassment. The theoretical background of moral emotions within cognitive neuroscience has been introduced together with research of the emotional brain and morality to further clarify the main topic of this thesis, moral emotions and their neural correlates. Moral emotions are very crucial in understanding humans’ behavioural adherence to their moral standards. For example, shame is described as the way we relate and perceive ourselves. It is related to how we believe and think other people see us and our incompetence or failure to fulfil the desire to be a good person, e.g. “I think, feel and believe that I am a bad person for lying to someone”. These topics have been discoursed through this thesis showing significant results. There are many neural regions, e.g. medial prefrontal cortex (mPFC) and posterior superior temporal sulcus (pSTS) which get activated whilst experiencing distinct moral emotions. However, studies have shown that there is no one-to-one correspondence between a specific brain area and a specific emotion, instead, research has suggested there are particular topographical anatomical networks in the brain which get activated when experiencing different emotions. There are few studies in this field; their results should be taken with caution. The field continues to grow, and we can learn more about moral emotions and their neural correlates today and in the future.

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Broom, Timothy W. « The Neural Correlates of Parasocial Relationships ». The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531764814960927.

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Ray, Rebecca D. « Neural correlates of self-referential processing / ». May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.

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Meulemans, Daniel Keith Fraser Scott E. « Genetic correlates of neural crest evolution / ». Diss., Pasadena, Calif. : California Institute of Technology, 2004. http://resolver.caltech.edu/CaltechETD:etd-09292003-170037.

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Lidén, Josefin. « Intrinsic Motivation and its Neural Correlates ». Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-17612.

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Why is motivation important? The answer is simple to most of us: it is what makes people push forward and act. Intrinsic motivation is the kind of motivation that arises from within a person, making her or him strive towards a goal for no other reward than the feeling it will bring. Additionally, this kind of motivation has shown correlations with enhanced learning, creativity, performance, optimal development, and well-being. While intrinsic motivation has long been a topic within the field of psychology, the neural correlates underlying it have only recently become of interest for researchers, and studies have shown some interesting but also contradictory findings. Therefore, the aim of this literature review thesis is to investigate the neural correlates of intrinsic motivation further. Firstly, a background review of motivation in general and intrinsic motivation in particular is presented, focusing on concepts such as the self-determination theory, flow, and cognitive evaluation theory. This is followed by a chapter on motivation- and intrinsic motivation from a neuroscientific perspective, concerning concepts such as the reward system, the undermining effect, and studies examining the neural correlates of intrinsic motivation. These studies show that there was activity in several different areas when participants were intrinsically motivated. However, a frequent pattern of activity in dopaminergic pathways involving the striatum and the prefrontal cortex (PFC) was detected in most studies, indicating the involvement of these areas in particular when a person is intrinsically motivated.

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Tanguay, Annick. « The Neural Correlates of Personal Semantics ». Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38251.

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The long-term memory system for what is conscious and can be verbalized – declarative memory- is often separated into memory for general facts and memory for personal events (Squire, 2009; Tulving, 2002). Personal semantics share elements of both semantic memory (i.e., they are facts that can be known) and episodic memory (i.e., they are self-related and idiosyncratic; Renoult, Davidson, Palombo, Moscovitch, & Levine, 2012). According to the taxonomy of personal semantics (Renoult et al., 2012), they vary in proximity to either semantic or episodic memory. Towards one end of the continuum, memory for autobiographical facts such as jobs and names of friends were hypothesized to be closer to general facts. Towards the other end of the continuum, repeated events are summaries of the core elements of similar events that happened more than once (e.g., getting coffee at a coffee shop), and they were hypothesized to be closer to episodic memory (i.e., the recollection of a unique event). Self-knowledge involves self-reflection about one’s own personality traits and preferences; it was thought to be the most distinct from semantic and episodic memory. However, little research had compared personal semantics to both semantic and episodic memory, or to one another, and these proposals needed to be tested experimentally. In this thesis, I compared the neural correlates of three types of personal semantics to semantic memory (study 1, 2, 3) and episodic memory (study 1, 2), and to one another (study 1) using functional magnetic resonance imaging (fMRI; study 1) and event related potentials (ERPs; study 2, 3). Moreover, I examined whether temporal orientation modified the personal semantics’ relationship to the typically atemporal semantic memory (study 2, 3) and to the typically past-oriented episodic memory (study 2). In study 1, general facts, autobiographical facts, repeated events, and unique events were compared using fMRI, in a follow-up to an ERP study (Renoult et al., 2016). In our analyses of the hippocampus (HPC) and posterior medial network (Ritchey, Libby, & Ranganath, 2015), general semantics and autobiographical facts were often not significantly different from one another (except for the left posterior HPC), and repeated events and unique events did not differ from one another in any comparison. I observed a small graded increase of brain activity from general facts to autobiographical facts to repeated events and unique events (with a significant linear trend) in the left posterior HPC. In contrast, no memory type differed in the anterior temporal network (Ritchey et al., 2015). In study 2 and 3, self-knowledge was operationalized as the knowledge of one’s own traits, and could concern past (study 2), present (study 2, 3) and future selves (study 2, 3). A neural correlate of recollection, the Late Positive Component (LPC), had a larger mean amplitude for thinking about the self than others (study 2, 3), and thinking about a past and/or future self than the present self (on average for study 2, and significant for study 3). The amplitude of the LPC for thinking about the past and future selves did not differ from an episodic recognition memory task (or present self-knowledge; study 2). Further, the temporal orientation effect was smaller and not significant when we compared thinking about the present and the future traits of others (study 3). The operationalization of the “other” as a close friend or a group of people did not modify this result (study 3). Together, in addition to Renoult et al. (2016), these findings suggest that: the neural correlates of autobiographical facts, repeated events, and self-knowledge do not overlap perfectly with semantic or episodic memory. Moreover, the temporal orientation of the knowledge is one factor that can influence the proximity of the neural correlates of personal semantics to either semantic or episodic memory.

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Wisniewski, David. « The neural correlates of intentional control ». Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17500.

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Intentionale Kontrolle ist ein fundamentaler Aspekt menschlichen Verhaltens. Jedoch gibt es bei der neuronalen Basis solcher Kontrollprozesse noch immer viele offene Fragen. Bis heute bleibt beispielsweise umstritten wie das frontoparietale Intentions-Netzwerk organisiert ist. Weiterhin üben motivationale Prozesse einen großen Einfluss auf intentionale Kontrollprozesse aus. In früheren Studien wurden motivationale und intentionale Kontrollprozesse jedoch oft als unabhängige Funktionen verstanden und untersucht. Diese Dissertation untersucht die neuronalen Grundlagen intentionaler Kontrolle, vor allem auf den Einfluss zweier motivationaler Variablen (Aufgabenschwierigkeit, monetäre Belohnungen) und die funktionelle Organisation des Kontrollnetzwerkes fokussierend. Experiment 1 untersuchte Effekte motivationaler Prozesse auf volitionales Verhalten sowie die neuronale Grundlage dieser Effekte. Experiment 2 untersuchte welche Hirnregionen Verhalten mit seinen Konsequenzen assoziiert. Dies ist eine zentrale Funktion, möchte man die positiven Konsequenzen eigenen Verhaltens maximieren. Experiment 3 untersuchte direkt die Repräsentationen frei gewählter und extern determinierter Intentionen und somit auch die funktionale Architektur des intentionalen Kontrollnetzwerkes. Die Ergebnisse aller drei Studien betonen die Wichtigkeit des anterioren zingulären Kortex, dorsomedialen Präfrontalkortex und des parietalen Kortex für die Vermittlung motivationaler Effekte auf intentionale Kontrolle. Weiterhin deuten die Ergebnisse darauf hin, dass das frontoparietale Kontrollnetzwerk sowohl für die Kontrolle frei gewählten als auch extern determinierten Verhaltens wichtig ist. Diese Ergebnisse stellen einen wichtigen Beitrag für aktuelle Debatten über die neuronale Grundlage intentionalen Verhaltens dar, und erweitern aktuelle Theorien über motivationale und intentionale Kontrolle.
Freely choosing one’s own course of action is a fundamental aspect of human behavior. Yet, despite its importance, there remain many open questions about the neural basis underlying intentional control of action. On the one hand, the functional organization of the fronto-parietal brain network associated with intentional control remains a debated topic. On the other hand, motivational processes evidently affect intentional control, as we often choose actions which promise desirable outcomes. Despite this, previous research largely treated intentional and motivational control as two independent functions. This thesis aims at shedding light on the neural basis of intentional control, focusing on the effects of two motivational variables on intentional control processes (effort, monetary rewards), as well as the functional organization of the intentional control network. Experiment 1 investigated the effect of motivational processes on voluntary behavior and its neural basis. Experiment 2 assessed which brain regions associate behaviors with their outcomes, an important piece of information for choosing actions which lead the most desirable outcomes. Experiment 3 directly contrasted the representations of freely chosen and externally cued intentions, in this way investigating the functional organization of the intentional control network. Overall, results from those three experiments highlight the role of the dorsal anterior cingulate, dorso-medial prefrontal, and parietal cortex in mediating motivational effects on intentional control. They further suggest that the fronto-parietal intentional control network likely has a role in both controlling behavior that is freely chosen and externally cued. These results inform debates on the neural basis of intentional control and extend some recent theories of motivational and intentional control functions. They provide a promising starting point for a systematic investigation of the neural basis of intentional control.

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Golestani, Narly A. « Phonetic learning abilities : behavioral, neural functional, and neural anatomical correlates ». Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38196.

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The studies included in this thesis had as aim to elucidate how individual differences in phonetic learning abilities might be related to differences in more general, psychoacoustic learning abilities, and in how they might be related to differences in brain function and brain morphology.
We tested and trained English speaking volunteers to perceive the Hindi dental-retroflex phonetic contrast. We found evidence suggesting that the ability to accurately perceive "difficult" non-native contrasts is not permanently lost during development. We also tested and trained subjects to perceive the difference between non-linguistic rapidly changing and steady-state tonal sounds, and found evidence supporting the hypothesis that successful phonetic learning is in part a function of a more general psychoacoustic ability to process rapidly changing sounds.
The aim of the second study was to determine how the pattern of brain activity may change as a result of training with non-native speech sounds, and in whether it is possible to differentiate "learners" from "non-learners" on the basis of neural activation patterns. Results of this functional magnetic resonance imaging (fMRI) investigation suggested that successful learning of a non-native contrast results in the recruitment of the same areas that are involved in the processing of native contrasts; but the degree of success in learning is accompanied by more efficient neural processing in classical frontal speech regions, while making greater processing demands in left parieto-temporal speech regions.
In the final study, we correlated phonetic learning measures with brain morphology throughout the whole brain volume. We found evidence for overall larger parietal volumes in the left relative to the right hemisphere, and for more white relative to gray matter in the left hemisphere in the learners and not in the nonlearners. This finding is consistent with findings by other investigators suggesting that left-hemispheric dominance for speech may be in part accounted for by hemispheric differences in white matter connectivity, which may allow faster intra- and inter-hemispheric neural transmission. This latter feature may be critical for the processing of consonant speech sounds, which depends on the ability to process sounds that change on the time scale of 30--50 milliseconds.

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Wimber, Maria. « Neural correlates of inhibition in episodic memory ». kostenfrei, 2008. http://www.opus-bayern.de/uni-regensburg/volltexte/2009/1123/.

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Martín, Salguero Ana María. « Behavioral and neural correlates of logical inferences ». Doctoral thesis, Universitat Pompeu Fabra, 2021. http://hdl.handle.net/10803/671350.

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The aim of the dissertation is to explore behavioral and neuropsychological correlates of elementary deductive processes in infants and adults. To this purpose, we introduce a novel non-verbal task presenting scenes containing an ambiguity which could be resolved by the application of an elementary logical rule (A or B, not A, therefore B). In a series of studies we identified oculomotor responses associated with logical inference processing, substantially stable across development, indicating that some logical rules may be at the core of human cognition and occur independently of language. Second, to further address the nature of this process, we conducted imaging studies to describe the brain networks involved in elementary nonverbal deduction.In adults, an fMRI study revealed activity in the prefrontal and occipital cortices associated to a logical representation, and a left fronto-parietal activity associated to a logical inference, indicating that also non-verbal reasoning is made by a cascade of process of different nature. A fNIRS study in 12-month-olds revealed a more extended and bilateral activation with respect to adults, with oculomotor data indicating the cost associated to both logical components. Our results show that non-verbal reasoning is a multiple component process substantially similar across development, perhaps undergoing a neural reorganization from infancy to adulthood.
El objetivo de esta tesis es el de explorar correlatos conductuales y neuropsicológicos de procesos deductivos básicos en bebés y adultos. Para ello diseñamos un tarea no verbal novedosa que consiste en la presentación de escenas que contienen una ambigüedad y puede ser resulta mediante la aplicación de una regla lógica básica (A o B, no A, entonces B). A través de varios estudios, identificamos respuestas oculomotoras asociadas a la realización de una inferencia lógica sustancialmente estables a lo largo del desarrollo, esto indica que algunas reglas lógicas pueden ser parte del núcleo de la cognición humana y ocurrir independientemente del lenguaje. Segundo, para aclarar la naturaleza de este proceso, realizamos estudios de imagen funcional para describir las areas cerebrales implicadas en procesos elementales de deducción no verbal. En adultos, un estudio basado en fMRI, mostró actividad en áreas prefrontales and occipitales asociada a los procesos de representación lógica, y actividad fronto-parietal asociada a la realización de inferencias lógicas, indicando que incluso el razonamiento no verbal está compuesto por una cascada de procesos de naturaleza diferente. Un estudio de fNIRS en bebés de 12 meses reveló un perfil de activación bilateral y más extendido en relación a los adultos, con respuestas oculomotoras que señalan el coste asociado a los dos componentes lógicos. Nuestros resultados muestran que el razonamiento no verbal es un proceso con múltiples componentes en gran medida similar a lo largo del desarrollo, quizá sometido a una reorganización neuronal desde la infancia a la edad adulta.

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Löfstrand, Emelie. « Empathy for Pain : And its Neural Correlates ». Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-12795.

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The phenomenon of empathy has been fascinating laymen and scholars for centuries and has recently been an important subject for cognitive neuroscientific study. Empathy refers to the ability to understand and share others’ emotions and a characteristic of this ability is the capacity to empathize with others in pain. This review intends to examine and read up on the current state of the field of the neural and behavioral mechanisms associated with empathy for pain. The neural underpinnings of the first-hand experience of pain have been shown to be activated in a person observing the suffering individual, and this similarity in brain activity has been referred to as shared networks. This phenomenon plays an important role in the study of empathy. However, different factors have been shown to influence empathy for pain, such as age, gender, affective link between observer and sufferer, as well as phylogenetic similarity. This thesis discusses these differences, as well as atypical aspects affecting the empathic ability such as synaesthesia for pain, psychopathy and Asperger’s disease. Further, empathy for pain can be modulated by the individual observing someone in pain. For example, caregivers often down-regulate their empathic response to patients in pain, possibly in order to focus on their treatment and assistance. Also, paying attention to harmful stimuli heightens the perception of pain; therefore, the painful experience can be less remarkable when focusing on something else. The effect of empathy from others directed to oneself when suffering is discussed, as well as the consistency and limitations of presented research.

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Roos, Magnus. « Speech Comprehension : Theoretical approaches and neural correlates ». Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-11240.

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This review has examined the spatial and temporal neural activation of speech comprehension. Six theories on speech comprehension were selected and reviewed. The most fundamental structures for speech comprehension are the superior temporal gyrus, the fusiform gyrus, the temporal pole, the temporoparietal junction, and the inferior frontal gyrus. Considering temporal aspects of processes, the N400 ERP effect indicates semantic violations, and the P600 indicates re-evaluation of a word due to ambiguity or syntax error. The dual-route processing model provides the most accurate account of neural correlates and streams of activation necessary for speech comprehension, while also being compatible with both the reviewed studies and the reviewed theories. The integrated theory of language production and comprehension provides a contemporary theory of speech production and comprehension with roots in computational neuroscience, which in conjunction with the dual-route processing model could drive the fields of language and neuroscience even further forward.

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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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Sollini, Joseph A. « Behavioural and neural correlates of binaural hearing ». Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13739/.

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The work in this thesis involves two separate projects. The first project involves the behavioural measurement of auditory thresholds in the ferret (Mustela Putorius). A new behavioural paradigm using a sound localisation task was developed which produces reliable psychophysical detection thresholds in animals. Initial attempts to use the task failed and after further investigation improvements were made. These changes produced a task that successfully produced reliably low thresholds. Different methods of testing, and the number of experimental trials required, here then explored systemically. The refined data collection method was then used to investigate frequency resolution in the ferret. These data demonstrated that the method was suitable for measuring perceptual frequency selectivity. It revealed that the auditory filters of ferrets are broader than several other species. In some cases this was also broader than neural estimates would suggest. The second project involved the measurement of neural data in the Guinea Pig (Cavia porecellus). More specifically the project aimed to test the ability of the primary auditory cortex (AI) to integrate high frequency spatial cues. Two experiments were required to elucidate these data. The first experiment demonstrated a relationship between frequency and space, though these data proved noisy. A second experiment was conducted, focussing on improving the quality of the data this allowed for a more quantitative approach to be applied. The results highlighted that though AI neurons are responsive over a broad frequency range, inhibitory binaural interactions integrate spatial information over a smaller range. Binaural interactions were only strong when sounds in either ear were closely matched in frequency. In contrast, excitatory binaural interactions did not generally depend on the interaural frequency difference. These findings place important constraints on the across frequency integration of binaural level cues.

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Davies, Jodie. « The neural correlates of familiar face recognition ». Thesis, University of York, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.535061.

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Roberts, Katherine Leonie. « Behavioural and neural correlates of auditory attention ». Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/12223/.

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The auditory attention skills of alterting, orienting, and executive control were assessed using behavioural and neuroimaging techniques. Initially, an auditory analgue of the visual attention network test (ANT) (FAN, McCandliss, Sommer, Raz, & Posner, 2002) was created and tested alongside the visual ANT in a group of 40 healthy subjects. The results from this study showed similarities between auditory and visual spatial orienting. An fMRI study was conducted to investigate whether the similar behavioural measures of auditory and visual executive control were the result of common cortical mechanisms. The results were consistent with a supramodal anterior network involved in conflict monitoring and resolution. Auditory orienting of attention was investigated through a series of behavioural experiments. The first investigated listeners' ability to benefit from cues to location, to pitch, and to both location and pitch, in a vowel-identification task. Subjects were able to benefit from all three types of cues but did not gain additive benefit from being cued to both location and pitch, suggesting that attention was being directed to an auditory object comprising both features. The following seven experiments investigated auditory spatial orienting in non-spatial tasks. These experiments revealed a robust exogenous (automatic) auditory orienting effect, which was relatively insensitive to task differences. However, endogenous (voluntary) auditory orienting effects were small and highly variable across subjects. It is hypothesised that differences between auditory and visual spatial orienting reflect the relative importance of spatial information in the two modalities, and differences in the neural coding of auditory and visual spatial information.

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Gerdfeldter, Billy. « Exploring the Neural Correlates of Auditory Awareness ». Thesis, Stockholms universitet, Psykologiska institutionen, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-157188.

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Neural correlates of consciousness (NCCs) represent the physiological processes related to consciousness and awareness. Consciousness is theorized as a recurrent process of integration between separate but specialized brain areas. Previous research has used electroencephalography (EEG) to locate NCCs of sensory awareness in vision through event-related potentials (ERPs). Two ERP components thought to represent visual awareness are the visual awareness negativity (VAN) and late positivity (LP). VAN and LP have been extensively studied, yet little research has been conducted in other sensory modalities. In this study, the presence of an auditory awareness negativity (AAN) and associated LP is investigated in 23 subjects using EEG. To avoid false positives in data analysis, two research hypotheses were preregistered. The results indicate that auditory LP does occur, but that AAN does not, in hypothesized intervals. However, the data suggest that AAN may occur at a later interval. Possible attributes of the later interval are discussed. In sum, the data provide results consistent with recurrent theories of sensory awareness.

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Lim, Lena Hui Xiang. « Neural correlates of physical abuse in childhood ». Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/neural-correlates-of-physical-abuse-in-childhood(f38953f6-9849-459c-a8f7-a7c15fc97f51).html.

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Childhood maltreatment is associated with impaired inhibition, attention, emotion processing and hypersensitivity to mistakes. This thesis includes a metaanalysis of published whole-brain voxel-based morphometry studies in childhood maltreatment to elucidate the most robust volumetric grey matter (GM) abnormalities and an fMRI study that examined the association between childhood (physical) abuse and brain functionality in the domains of inhibition, attention, error and emotion processing. The participants were medication naïve, drug-free young people and psychiatric comorbidities were controlled for by including a psychiatric control group. Anisotropic effect size-signed differential mapping was used to conduct the meta-analysis. For the fMRI study, brain activation was compared between 23 ageand gender-matched young people who had experienced childhood (physical) abuse, 20 psychiatric controls matched for psychiatric diagnoses with the participants exposed to abuse and 27 healthy controls while they performed a tracking stop-signal task designed to elicit 50% inhibition failures, a parametrically modulated vigilance task and an emotion processing task. The meta-analysis showed that the most consistent GM abnormalities in childhood maltreatment were in relatively late-developing ventrolateral prefrontallimbic- temporal regions. The participants who had experienced abuse showed hyperactivation in typical error processing regions of the dorsomedial frontal cortex which was abuse-specific relative to healthy and psychiatric controls. No group differences in activation were observed for successful inhibition. The participants with a history of abuse exhibited reduced activation in typical dorsal and ventral frontostriato- thalamo-cerebellar sustained attention regions relative to healthy controls during the most challenging attention condition only, and showed an abuse-specific linear trend of decreasing activation with increasing attention loads in these regions. They also demonstrated abuse-specific hyperactivation of classical fear processing regions of ventromedial prefrontal and anterior cingulate cortices to fearful faces and in fronto-striato-temporo-limbic regions to neutral faces relative to non-maltreated controls. The findings suggest an environmentally triggered disturbance in the normal development of these cognitive and affect networks as a consequence of childhood abuse.

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Eugene, Fanny. « Neural correlates of inhibitory dysfunction in depression / ». May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.

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Brundin, Malin. « Binge Eating Disorder : Neural correlates and treatments ». Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-17594.

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Binge eating disorder (BED) is the most prevalent of all eating disorders and is characterized by recurrent episodes of eating a large amount of food in the absence of control. There have been various kinds of research of BED, but the phenomenon remains poorly understood. This thesis reviews the results of research on BED to provide a synthetic view of the current general understanding on BED, as well as the neural correlates of the disorder and treatments. Research has so far identified several risk factors that may underlie the onset and maintenance of the disorder, such as emotion regulation deficits and body shape and weight concerns. However, neuroscientific research suggests that BED may characterize as an impulsive/compulsive disorder, with altered reward sensitivity and increased attentional biases towards food cues, as well as cognitive dysfunctions due to alterations in prefrontal, insular, and orbitofrontal cortices and the striatum. The same alterations as in addictive disorders. Genetic and animal studies have found changes in dopaminergic and opioidergic systems, which may contribute to the severities of the disorder. Research investigating neuroimaging and neuromodulation approaches as neural treatment, suggests that these are innovative tools that may modulate food-related reward processes and thereby suppress the binges. In order to predict treatment outcomes of BED, future studies need to further examine emotion regulation and the genetics of BED, the altered neurocircuitry of the disorder, as well as the role of neurotransmission networks relatedness to binge eating behavior.

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Åberg, Emma. « Investigating the Neural Substrates and Neural Markers of Optimism and Optimism Bias : A Systematic Review ». Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-20609.

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Optimism refers to peoples’ general tendency to anticipate good outcomes in areas that are important to them. Numerous studies have shown that optimism is significantly correlated with improved physical and mental health. Optimism can come to an overly optimistic degree, called optimism bias. People generally expect better outcomes and fewer negative events to happen for themselves in the future compared to the average person. There are two sides to this: being optimistically biased might lead to risky behavior, but it might also ease people's worries about the future. To have a consistently negative view is suggested to correlate with depressive symptoms and worsened health. The aim of this thesis is to investigate the neural correlates and functional markers of optimism and optimism bias. Optimism is suggested to correlate with gray-matter volume in the thalamus, orbitofrontal cortex (OFC), and bilateral putamen. The inferior frontal gyrus (IFG) and the rostral anterior cingulate cortex (rACC) have a crucial role in dismissing undesirable information and self referential processing. Research regarding this issue might be beneficial for further understanding of the connection between optimism and well-being.

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Mestres, Missé Anna. « Neural correlates of word learning and meaning acquisition ». Doctoral thesis, Universitat de Barcelona, 2007. http://hdl.handle.net/10803/2633.

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The series of studies that comprise this dissertation are aimed at simulating vocabulary learning and meaning acquisition of different types of words, namely words which differ in imageability. For this purpose, the human simulation paradigm is the best option to approach the question of how the meanings of words are learned. It also offers the advantage of using electrophysiological and hemodynamic techniques to explore the underlying processes and neural regions that sustain on-line word learning and that, with the use of infants, would have been difficult or impossible to study.

In order to study the meaning acquisition of new words, the human simulation paradigm was adopted (Gillette et al., 1999). In the first series of experiments (Chapters 2 and 3), adults were provided with congruent and incongruent semantic contexts from which they had to derive the meanings of new words. This strategy was further applied in order to understand the neural mechanisms involved in learning concrete and abstract words (Chapters 4 and 5).

More specifically, Chapter 2 analyzes the interaction of semantic information congruency and meaning resolution using event-related brain potentials (ERP) (experiments 1 and 3). A different experiment explores the effects of context congruence on lexical acquisition using a self-paced reading paradigm (experiment 2). Chapter 3 examines the localization of cortical areas of successful meaning acquisition with functional magnetic resonance imaging (fMRI), and investigates the neural network for lexical learning (experiment 4). In Chapter 4, the self¬paced reading paradigm is used to study meaning acquisition of concrete and abstract words. First, a reanalysis of experiment 2 is presented (experiment 2b). Experiment 5 investigates abstract word learning from congruent and incongruent sentential contexts. Afterward, a comparison between experiments 2b and 5 is presented. In experiment 6, the simultaneous acquisition of concrete and abstract words is studied using the self¬paced paradigm. Finally, Chapter 5 examines the localization of cortical areas differently involved in meaning acquisition of concrete and abstract words using fMRI (experiment 7).
El llenguatge és una capacitat humana que ha fet possible aspectes únics del pensament humà, com la creativitat, l'habilitat de pensar sobre el passat i el futur, la lògica i, totes les formes de cognició d'alt nivell. El llenguatge ens donà l'habilitat de mantenir informació de l'entorn en memòria per a poder manipular-la, i en conseqüència, tenir una eina per a comunicar idees. El llenguatge esdevingué la principal manera de transmetre i emmagatzemar el coneixement i la cultura. Degut a la importància d'aquesta increïble, però a la vegada, complicada habilitat, els humans hem d'aprendre'l durant els primers anys de vida. Un dels primers passos en aquest enigmàtic procés d'aprendre el llenguatge és aprendre les etiquetes del món. Donar un nom a quelcom optimitza la informació, i permet fer categoritzacions, que permeten generalitzacions del coneixement que ja existeix a nous exemplars, objectes o conceptes. Sota una etiqueta arbitrària, una convenció social, les característiques, funcions, parts i relacions amb altres paraules d'un concepte són emmagatzemades. L'aprenentatge d'aquestes etiquetes és un dels primers reptes que els infants han d'afrontar. Per tal d'esdevenir un usuari expert del llenguatge els infants primer han d'aprendre com es denominen les coses, quines coses pertanyen al mateix grup i quines no, és a dir, han d'aprendre a categoritzar el món i generalitzar la informació. Els infants són extremadament bons en això. Els nens comencen a produir les primeres paraules al volant del 12 mesos d'edat, aprenent unes 10 paraules noves cada dia fins al final de la secundaria. Nogensmenys, l'aprenentatge de vocabulari no s'atura al final de l'adolescència, constantment trobem paraules noves, neologismes, argots, que hem d'aprendre. A més a més, la majoria de gent haurà d'aprendre com a mínim una llengua estrangera durant la seva vida. Tot i això, l'adquisició de vocabulari en l'adultesa és molt més lenta i probablement depèn més de factors socials.

Aquesta tesi està dedicada a la comprensió de com els adults aprenen el significat de noves paraules a partir del context semàntic, és a dir, estudia la vinculació d'una paraula amb un concepte utilitzant la informació semàntica proporcionada per les oracions en les que la paraula nova es troba.

Així doncs, per a aquest propòsit, s'han realitzat set experiments. Dos experiments amb potencials evocats, un conductual i un utilitzant ressonància magnètica funcional (fMRI) es centren en l'efecte de la congruència del context semàntic en l'adquisició lèxica. Els següents experiments intenten profunditzar en l'aprenentatge de noves paraules investigant l'adquisició de paraules concretes i abstractes. Amb aquest propòsit s'han realitzat dos experiments conductuals i un utilitzant fMRI.

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Martínez-García, Marina. « Statistical analysis of neural correlates in decision-making ». Doctoral thesis, Universitat Pompeu Fabra, 2014. http://hdl.handle.net/10803/283111.

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We investigated the neuronal processes which occur during a decision- making task based on a perceptual classi cation judgment. For this purpose we have analysed three di erent experimental paradigms (somatosensory, visual, and auditory) in two di erent species (monkey and rat), with the common goal of shedding light into the information carried by neurons. In particular, we focused on how the information content is preserved in the underlying neuronal activity over time. Furthermore we considered how the decision, the stimuli, and the con dence are encoded in memory and, when the experimental paradigm allowed it, how the attention modulates these features. Finally, we went one step further, and we investigated the interactions between brain areas that arise during the process of decision- making.
Durant aquesta tesi hem investigat els processos neuronals que es pro- dueixen durant tasques de presa de decisions, tasques basades en un ju- dici l ogic de classi caci o perceptual. Per a aquest prop osit hem analitzat tres paradigmes experimentals diferents (somatosensorial, visual i auditiu) en dues espcies diferents (micos i rates), amb l'objectiu d'il.lustrar com les neurones codi quen informaci on referents a les t asques. En particular, ens hem centrat en com certes informacions estan cod- i cades en l'activitat neuronal al llarg del temps. Concretament, com la informaci o sobre: la decisi o comportamental, els factors externs, i la con- ana en la resposta, b e codi cada en la mem oria. A m es a m es, quan el paradigma experimental ens ho va permetre, com l'atenci o modula aquests aspectes. Finalment, hem anat un pas m es enll a, i hem analitzat la comu- nicaci o entre les diferents arees corticals, mentre els subjectes resolien una tasca de presa de decisions.

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Labbé, Daniel. « The Feeling of Anxiety : Phenomenology and neural correlates ». Thesis, University of Skövde, School of Humanities and Informatics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-2273.

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The feeling of anxiety, a conscious experience, is associated with uneasiness, painfulness, or disturbing suspense. The current paper presents the phenomenology of anxiety disorders based on diagnostic criteria and reviews neuroimaging studies on anxiety including dissociation studies. Activity in the anterior cingulate cortex, medial prefrontal cortex, insula, temporal poles and amygdala suggest neural correlates of anxiety. The relevance of the neural correlates, how the feeling of anxiety differs from fear and worry, and the construct validity of anxiety are addressed. Anxiety and pain correlate with activity in the anterior cingulate cortex, which warrants further studies on the painfulness–anxiety relationship.

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Jazayeri, Mina. « Neural correlates of socio-emotional states in macaques ». Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1281/document.

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Un pilier d'une vie sociale fructueuse est la capacité de prédire correctement les actions des autres et de percevoir leurs états émotionnels. Des études d'interaction sociale chez les primates ont montré qu'ils sont capables de déduire ce que les autres peuvent entendre ou voir, et de prédire leurs émotions et intentions. Il a été montré qu'ils peuvent manifester différents degrés de comportements prosociaux, allant de la coopération jusqu'à des comportements altruistes et empathiques. Des études d'imageries fonctionnelles chez l'homme ont identifié l'insula antérieur (AI) comme une région cérébrale clé dans le traitement de l'empathie.Spécifiquement, cette région apparait comme l'aire intégratrice des activités liées à la douleur ressentie et observée, suggérant que l'empathie pourrait impliquer un modèle « miroir » des propriétés affectives et sensorielles de la douleur d'autrui. Cependant, les bases neuronales de ce processus n'ont pas encore été découvertes. Dans le but d'examiner le rôle de l'AI dans le traitement de l'empathie, nous avons enregistré l'activité des neurones dans l'AI de deux singes pendant qu'ils sont engagés dans une tâche sociale leur permettant de délivrer un stimulus aversif ou appétitif à leur partenaire, à lui-même ou à personne. Les résultats comportementaux ont montré que les singes prennent en compte le bien-être de leur partenaire. Les données neuronales rapportent différentes populations neuronales répondant aux stimuli aversif ou appétitif et ceux délivrés à soi ou à autrui. Notamment, la population neuronale répondant au stimulus aversif a montré trois profils d'activité : une représentation neuronale de l'expérience désagréable du partenaire, une représentation neuronale de sa propre sensation désagréable et une minorité de neurones montrant des propriétés miroirs entre soi et autrui. Nos résultats suggèrent un modèle neuronal de l'empathie représentant des propriétés distinctes entre l'expérience vécue et observée
A cornerstone of a successful social life is the ability to correctly predict others’ actions and empathically perceive their emotional states. Studies on primates’ social interaction have shown that thanks to their keen cognitive abilities monkeys are able to deduce what others can hear or see, and to predict others’ emotions and intentions. It has been shown that primates are able to display different degrees of prosocial behavior, from cooperation to even altruism and empathically driven behavior. Studies using fMRI techniques inhumans have identified the anterior insula (AI) as a key brain region in the processing of empathy. More precisely, this region emerged as the overlapping area activated for both experienced and observed pain,leading to the idea that empathy for pain may involve a mirror-matching model of the affective and sensory features of others' pain. However, the neuronal basis of this process has yet to be uncovered. In an attempt toextend and to investigate the role of the AI in the process of empathy we have recorded single cell activity inthe AI of two monkeys while they were engaged in a social task where based on the performed trials positiveor negative reinforcements could be delivered to self, another monkey, or nobody. Behavioral results showed that monkeys take into account the welfare of their partners even when this has no impact on their ownwelfare. Our neuronal findings report that distinct population of neurons respond differentially to outcomesfor self and other, and to appetitive and aversive outcomes. Interestingly the neuronal population responding to the aversive outcome showed mainly three profiles of activity: neuronal representation of conspecifics’unpleasant experience, neuronal representation of own unpleasant experience and a minority of neurons showing mirroring properties between self and other. Thus, our results suggest a neuronal model of empathy that accounts for the distinctive features between feeling and empathizing

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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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Zárate, Jean Mary. « Neural correlates of vocal pitch regulation in singing ». Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66721.

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Precise vocal pitch regulation is crucial for the accurate production of notes and melodies in singing. The integration of auditory feedback with the vocal motor system, known as audio-vocal integration, is essential for vocal pitch regulation; however, its neural substrate is not well understood. This thesis consists of three functional magnetic resonance imaging (fMRI) experiments designed to investigate the neural mechanisms underlying vocal pitch regulation, and to evaluate the effects of training on vocal performance and neural activity involved in vocal pitch regulation. In Experiment 1, we tested non-musicians and experienced singers with singing tasks to find experience-dependent neural substrates of audio-vocal integration. To target brain activity relevant for audio-vocal integration, we used pitch-shifted auditory feedback and instructed subjects either to adjust or ignore the shifted feedback. Experiment 2 used a similar fMRI paradigm with large and small pitch shifts to distinguish between voluntary and involuntary vocal pitch regulation and to elucidate the neural mechanisms governing each type of vocal pitch regulation. In Experiment 3, we trained non-musicians in an auditory discrimination task and administered perceptual discrimination and singing tasks to determine whether training-enhanced auditory discrimination would result in improved vocal accuracy. We also used fMRI to evaluate any training-induced modulations within brain regions involved in singing and audio-vocal integration. Collectively, the behavioral data showed that correcting for pitch-shifted feedback is an automatic process, whereas ignoring shifted feedback requires training. The imaging data confirmed the existence of a singing network, comprised of auditory cortex, anterior cingulate cortex, insula, motor and premotor areas, thalamus, and cerebellum; within this network, experienced singers recruit additional activity in the superior
En chant, la précision vocale de la hauteur tonale est absolument cruciale pour une production juste des notes et des mélodies. L'intégration d'un retour auditif et du système vocal moteur, connu sous le terme intégration audio-vocale, est essentielle pour la régulation vocale des hauteurs ; toutefois, ses substrats neuronaux demeurent incompris. Cette thèse comporte trois expériences d'imagerie par résonnance magnétique fonctionnelle (IRMf), visant à explorer les mécanismes neuronaux sous-jacents à la régulation vocale de la hauteur et les effets d'entraînement. Dans l'Expérience 1, nous avons testé des non-musiciens et des chanteurs expérimentés avec des tâches de chant pour identifier les substrats neuronaux de l'intégration audio-vocale liés à l'expérience. Afin de cibler l'activité cérébrale pertinente à l'intégration audio-vocale, nous avons utilisé un retour auditif dont la hauteur était modifiée. Les sujets devaient ajuster ou ignorer la modification du retour. L'Expérience 2 utilise un paradigme d'IRMf similaire, où les modifications de la hauteur du retour sont petites ou grandes. Les objectifs sont doubles : distinguer la régulation volontaire et involontaire de la hauteur vocale, et élucider les mécanismes neuronaux qui gouvernent chaque type de régulation vocale. Dans l'Expérience 3, nous avons entraîné des non-musiciens dans une tâche de discrimination auditive pour déterminer si un entraînement de discrimination auditive améliorait la justesse vocale. Nous avons également utilisé l'IRMf pour évaluer si les modulations induites par l'entraînement influençaient l'activité de régions cérébrales impliquées dans le chant et l'intégration audio-vocale. Les données comportementales montrent que s'ajuster au retour modifié est automatique, alors qu'ignorer un retour modifié nécessite un entraînement. Les données confirment l'existence d'un réseau neuronal

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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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Roa, Romero Yadira [Verfasser]. « Neural correlates of multisensory processing / Yadira Roa Romero ». Berlin : Freie Universität Berlin, 2016. http://d-nb.info/1099952263/34.

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Heining, Maike. « The neural correlates of disgust : a multimodal investigation ». Thesis, King's College London (University of London), 2004. https://kclpure.kcl.ac.uk/portal/en/theses/the-neural-correlates-of-disgust--a-multimodal-investigation(586f5828-fbaf-4db7-a4ad-8b9c8975d7dc).html.

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Gallagher, Helen Louise. « Investigating the neural correlates of 'theory of mind' ». Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401204.

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Adapa, Ram Mohan. « Exploring neural correlates of higher cognition with sedation ». Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610446.

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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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Berg, Junker Maria Constance. « Neural correlates of romantic love and romantic attachment ». Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-16055.

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In the field of neuroscience, being in love and feeling romantically attached to a partner is described as a dynamic process. Romantic love may be viewed as a motivational system, changing throughout time and place, fluctuating on the interest and motivation of the individual. Early memories and attachment towards a caregiver, lay the foundation for later attachment behavior, also known as attachment styles. In this thesis, an exploratory approach is present. The thesis aims to introduce and describe the neural correlates of romantic love and romantic attachment. Brain regions concerned with reward, emotion and thought processing, such as the reward circuitry network of the brain and the limbic system, are being investigated. So are other brain areas involved in romantic love and romantic attachment. Research findings suggest that brain areas responsible for affection, emotional control, learning, memory and social judgment are all involved in the complex processes of being in love and feeling romantically attached. These findings are represented by the involvement of the frontal lobe, cerebral cortex, limbic system, orbitofrontal cortex, and hippocampus, anterior cingulate cortex (ACC), ventral tegmental area (VTA), caudate tail, including the reward pathways of the brain. Distribution and regulation of neurotransmitters such as; vasopressin, oxytocin, dopamine, corticosterone and serotonin are all present in the state of romantic attachment and romantic love. Overlapping evidence confirms the involvement of the reward circuitry network, together with the limbic system as crucial in the formation and maintenance of a romantic relationship.

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