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Gender Differences in the Neural Basis of Emotion Regulation: A Systematic ReviewFridlund, Angelina January 2022 (has links)
Gender differences in emotion regulation (ER) are well documented, but studies have often relied on behavioral and self-report data. Less is known about gender differences in the neural basis of ER. This systematic review aims to fill this gap and investigate gender differences in the neural basis of ER. The systematic search process ended in eight articles, using either structural or functional neuroimaging methods while investigating the neural correlates of ER using either an ER task to manipulate ER or assessed trait ER with questionnaires. The studies either used reappraisal or expressive suppression as ER strategies. The results were partly inconsistent, but most studies demonstrate the involvement of areas within the prefrontal cortex in ER. Males activated areas involved in cognitive control while females activated emotion-focused areas involved in emotional processing. There is disagreements among researchers whether more activity in the prefrontal cortex represent more effort during ER (and how it does so), as well as whetherless activity represent less effort or more efficient regulation. These insights may help us understand each other better. Future research is needed to address if activation within the prefrontal cortex reflects more or less efficiency when regulating emotions.
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Is There a You in Your Brain? : The Neuroscientific Support for the Bundle-Theory View of the Nature of the SelfVestin, Amanda January 2019 (has links)
Why do you experience yourself as a continuous self? This is a central question when regarding the self and it has two kinds of answers: either there is something like an ego inside you which is the entity perceiving all your experiences (the ego theory-view), or there is no such thing as a self or an ego and you are just a collection of different perceptions (the bundle theory-view). There are many different components all contributing to the concept of self as a whole leading to different neuroscientific ways of measuring it and some researchers are arguing for the nonexistence of a unified self-system within the brain. The aim of this thesis is to review how neuroscientific findings might contribute to the philosophical debate about the nature of self. The thesis starts off by reviewing the different concepts and components with which the self is typically described, both in philosophy and in the empirical research field of neuroscience. Then follows a presentation of three important aspects of self-awareness – first-person perspective, self-reflection, and interoception – and their specific associated brain areas (namely, the medial prefrontal cortex, the posterior and anterior cingulate cortices, and insula). The purpose here is to examine how the self is approached in these studies. After this the thesis explores to what extent neuroscience supports the bundle theory-view, with a focus on reviewing the different brain networks involved in the processing of self. In conclusion, the thesis suggests that the literature reviewed provides neuroscientific support for the bundle theory-view that there is no unified self located in the brain, mostly because of the dissimilar neural activations associated with different self-related processes. In other words, the bundle theory seems to be correct despite the experienced feeling you have of being a continuous and unified self.
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Commonalities and differences in visual and auditory multistabilityTaranu, Mihaela January 2018 (has links)
Perceptual bi/multi-stability—the phenomenon in which perceptual awareness switches between alternative interpretations of a stimulus—can be elicited by a large range of stimuli. The phenomenon is explored in vision, audition, touch, and even olfaction. The degree to which perceptual switching across visual and auditory bi/multi-stable paradigms depends on common or separate mechanisms remains unanswered. This main question was addressed in the current work by using four ambiguous tasks that give rise to bi/multi-stability and which are thought to involve rivalry at different levels of cognitive processing: auditory streaming and ambiguous-structure-from-motion (low- level tasks), and verbal transformations and ambiguous figures (high-level tasks). It was also investigated if individual differences in executive function (inhibitory control and set-shifting), creativity and personality traits have common relationships with perceptual switching in adults and children. A series of five experiments (four studies) were conducted. In Study 1 (two experiments), perceptual switching behaviour of adult participants was examined in the four perceptual tasks mentioned above. In Experiment 1, participants reported higher switching rates for the ambiguous figure and verbal transformations than for ambiguous motion and auditory streaming. However, in Experiment 2 participants had a higher switching rate in verbal transformations than in auditory streaming, while the switching rates in the two visual tasks did not differ significantly. The correlations between visual and auditory switching rates were similarly inconclusive: in Experiment 1, no cross-modal correlations emerged, while in Experiment 2 there were correlations between ambiguous figure and verbal transformations and between ambiguous motion and verbal transformation. Furthermore, inhibitory control, set-shifting, and creativity correlated with perceptual ii switching rates in some of the perceptual tasks, although not in a consistent manner. In Study 2, the development of perceptual switching was investigated in children in the same four tasks used in Study 1. Findings showed that the number of switches increased with age in all four perceptual tasks, indicating general maturational developments. Executive functions and creativity were not associated with the ongoing perceptual switching, which was similar to what was found in adults. In Study 3, a neuroscientific perturbation approach was used to investigate whether the superior parietal cortex is causally involved in both visual and auditory multistability as a top-down mechanism. Transcranial magnetic stimulation on the anterior and posterior superior parietal cortex did not increase or decrease the median phase durations in response to the ambiguous motion and auditory streaming. These regions were not causally involved in either visual or auditory multistability. Perceptual switching across modalities correlated nevertheless, indicating common perceptual mechanisms. In Study 4, the effects of attentional control and instructions were further investigated in ambiguous motion and auditory streaming. There were strong correlations between perceptual switching in the two tasks, confirming that there are common mechanisms. However, the effects of voluntary attention did not explain the commonalities found. Possibly the commonalities found reflect similar functionalities at more low-level sensorial mechanisms. In conclusion, perceptual switching in vision and audition share common mechanisms. These commonalities do not seem to be due to the same neural underpinning in parietal cortex. Moreover, attentional control does not explain the commonalities found, indicating a more low-level common mechanism or functionality. Perceptual switching across all ages is task-specific, more than modality specific. No central influence of inhibitory control and creativity was constantly associated with perceptual switching regardless of task/modality, supporting the distributed mechanisms hypothesis.
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Implication du striatum et du pallidum ventral dans le traitement de l'information aversive : approche électrophysiologique et pharmacologique chez le primate non-humain / Basal Ganglia implication in aversive information coding and active avoidance behavior : electrophysiological and pharmacological approach in non-human primateRichard, Augustin 16 December 2015 (has links)
Les ganglions de la base, auxquels appartiennent le striatum et le globus pallidus, sont un ensemble de structures sous-corticales impliquées dans des fonctions motrices, cognitives et motivationnelles. Il a également été montré qu’ils font partie du système de récompense, système assurant la motivation d’un organisme à initier des comportements d’approche, de façon à obtenir une récompense, puis à renforcer les activités ayant produit ces comportements pour pouvoir les reproduire par la suite, ce qui constitue la base de l’apprentissage instrumental. Or, dans certaines situations, le comportement à initier va dépendre d’une motivation à fuir ou à éviter un événement ou une situation aversive. Longtemps, on a pensé que le système du traitement des informations aversives était distinct de celui de la récompense, en termes de réseau et de régions cérébrales. Pourtant, de plus en plus d’études montrent à présent que les ganglions de la base ont certainement un rôle à jouer, non négligeable, dans le traitement des situations aversives. Dans ce travail de thèse, nous avons réalisé chez le primate non-humain des enregistrements d’activité neuronale et des perturbations pharmacologiques locales dans deux régions du système de récompense, le striatum antérieur et le pallidum ventral, au cours d’une tâche comportementale nécessitant tour à tour l’initiation de comportements d’approche vers une récompense et de comportements d’évitement d’un événement aversif. Nous avons montré l’existence d’un codage de l’information aversive dans ces régions tant pour un stimulus prédicteur d’un événement aversif, la préparation ou l’initiation d’un comportement d’évitement de cet événement, que pour l’anticipation et la réception de cet événement. Par ailleurs, les expériences de perturbations locales ont démontré qu’une atteinte du fonctionnement normal du striatum antérieur et du pallidum ventral affectait les comportements initiés normalement en contexte aversif. L’ensemble de ces résultats indique clairement que ces deux structures cérébrales, si elles sont impliquées dans la motivation à initier des comportements dirigés vers un but récompensant et l’apprentissage appétitif, le sont aussi dans la motivation aversive / Striatum and globus pallidus belong to the basal ganglia, which are a group of subcortical structures involved in motor, cognitive and motivational functions. They are also involved in the reward system which enables one’s motivation to initiate approach behaviors in order to get a reward and then consolidate activities that have produced these behaviors. This represents instrumental learning basis. However, in some situations, the behavior to be initiated depends on a motivation to escape or avoid an aversive situation. For a long time, it was thought that aversive information processing system and reward system depended on different networks and cerebral regions. Yet, a growing number of studies tend to show that basal ganglia certainly play an important role in aversive information processing. In this thesis, we recorded neuronal activity and performed local pharmacological perturbations in non-human primates, in two structures of the reward system, anterior striatum and ventral pallidum, while performing a behavioral task requiring them to initiate alternatively approach behaviors toward a reward and avoidance behaviors from an aversive event. We showed aversive information coding for the predictive stimulus, preparation and initiation of the avoidance behavior and anticipation and response to the aversive events. Furthermore, local perturbation experiments demonstrated that a functional impairment of the anterior striatum and the ventral pallidum affects the behaviors usually initiated by the animals in aversive context. Put together, these results clearly show that these two cerebral structures are involved in both appetitive and aversive motivations
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Left prefrontal and parietal contribution to sentence processing: a neuromodulation approachVercesi, Lorenzo 04 December 2023 (has links)
Describing a comprehensive neurofunctional model of sentence comprehension has always been a complex challenge. On one hand, disentangling the subprocesses that are necessary for computing the meaning of a sentence and their neural underpinnings is insidious. Each subprocess is closely interconnected with the others, and isolating only one as if it were separable can undermine the investigation of the overall process above. On the other hand, available data on the neural basis of sentence processing are not straightforward. This thesis explores relevant contributions and attempts to highlight open questions regarding the neural basis of two key processes in sentence comprehension, namely morphosyntactic processing and thematic role assignment. It presents and discusses original data resulting from an experiment that, to our knowledge, represents the first investigation of the neural basis of these two processes in the same sentential context. Results demonstrate that morphosyntactic and thematic processing rely on functionally distinct neural correlates in the left hemisphere. Morphosyntactic aspects are mostly processed in a left prefrontal network including the left inferior frontal gyrus (IFG) and the middle frontal gyrus (MFG), whereas thematic role assignment correlates with a left parietal node including the left intraparietal sulcus (IPS). Moreover, it is argued that results support the view that these regions play a language-related rather than domain-general role in human cognition. Finally, two statistical approaches to the analysis of the same TMS language data (ANOVA and Linear Mixed Models – LMMs) are compared. Their outcomes are discussed and an attempt is made at accounting for similarities and differences. Results suggest that the two models should not be considered on a sort of quality hierarchy according to which one has greater or lesser explanatory power than the other. Rather, they both represent legitimate and reliable approaches to account for data variability.
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An Investigation into the Neural Basis of Convergence Eye MovementsOwusu, Emmanuel 26 July 2018 (has links)
No description available.
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An fMRI comparison between younger and older adults of neural activity associated with recognition of familiar melodiesSikka, Ritu 16 September 2013 (has links)
We investigated age-related differences in neural activation associated with recognition of familiar melodies, a process that requires retrieval from musical semantic memory and leads to a feeling of familiarity. We used sparse sampling fMRI to determine the neural correlates of melody processing and familiarity by comparing activation when listening to melodies versus signal-correlated noise, and to familiar versus unfamiliar melodies, respectively. Overall, activity in the bilateral superior temporal gyrus correlated well with melody processing. Familiarity was associated with several frontal regions (bilateral inferior frontal gyrus, superior frontal gyrus, and precentral gyrus; left insular cortex), right superior temporal gyrus; left supramarginal gyrus and cingulate gyrus; bilateral putamen and thalamus; cerebellum and brainstem. No significant differences were found between younger and older adults for either melody processing or familiarity based activation. Assessment of familiarity-related group differences using less stringent criteria identified plausible areas; greater activation was seen bilaterally in the superior temporal gyrus in younger adults and in some left parietal regions in older adults. This study adds to the knowledge of musical semantic memory with results based on a large sample (N = 40) that includes older adults. Our findings for activation associated with melody processing and familiarity support some, but not all, previous results of related studies. We were unable to find conclusive evidence of age-related differences in neural correlates of musical semantic memory, while also being the first study (to the best of our knowledge) to search for these differences. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2013-09-16 12:38:10.757
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An fMRI comparison between younger and older adults of neural activity associated with recognition of familiar melodiesSikka, Ritu 16 September 2013 (has links)
We investigated age-related differences in neural activation associated with recognition of familiar melodies, a process that requires retrieval from musical semantic memory and leads to a feeling of familiarity. We used sparse sampling fMRI to determine the neural correlates of melody processing and familiarity by comparing activation when listening to melodies versus signal-correlated noise, and to familiar versus unfamiliar melodies, respectively. Overall, activity in the bilateral superior temporal gyrus correlated well with melody processing. Familiarity was associated with several frontal regions (bilateral inferior frontal gyrus, superior frontal gyrus, and precentral gyrus; left insular cortex), right superior temporal gyrus; left supramarginal gyrus and cingulate gyrus; bilateral putamen and thalamus; cerebellum and brainstem. No significant differences were found between younger and older adults for either melody processing or familiarity based activation. Assessment of familiarity-related group differences using less stringent criteria identified plausible areas; greater activation was seen bilaterally in the superior temporal gyrus in younger adults and in some left parietal regions in older adults. This study adds to the knowledge of musical semantic memory with results based on a large sample (N = 40) that includes older adults. Our findings for activation associated with melody processing and familiarity support some, but not all, previous results of related studies. We were unable to find conclusive evidence of age-related differences in neural correlates of musical semantic memory, while also being the first study (to the best of our knowledge) to search for these differences. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2013-09-16 12:38:10.757
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Neural basis and behavioral effects of dynamic resting state functional magnetic resonance imaging as defined by sliding window correlation and quasi-periodic patternsThompson, Garth John 20 September 2013 (has links)
While task-based functional magnetic resonance imaging (fMRI) has helped us understand the functional role of many regions in the human brain, many diseases and complex behaviors defy explanation. Alternatively, if no task is performed, the fMRI signal between distant, anatomically connected, brain regions is similar over time. These correlations in “resting state” fMRI have been strongly linked to behavior and disease. Previous work primarily calculated correlation in entire fMRI runs of six minutes or more, making understanding the neural underpinnings of these fluctuations difficult. Recently, coordinated dynamic activity on shorter time scales has been observed in resting state fMRI: correlation calculated in comparatively short sliding windows and quasi-periodic (periodic but not constantly active) spatiotemporal patterns. However, little relevance to behavior or underlying neural activity has been demonstrated. This dissertation addresses this problem, first by using 12.3 second windows to demonstrate a behavior-fMRI relationship previously only observed in entire fMRI runs. Second, simultaneous recording of fMRI and electrical signals from the brains of anesthetized rats is used to demonstrate that both types of dynamic activity have strong correlates in electrophysiology. Very slow neural signals correspond to the quasi-periodic patterns, supporting the idea that low-frequency activity organizes large scale information transfer in the brain. This work both validates the use of dynamic analysis of resting state fMRI, and provides a starting point for the investigation of the systemic basis of many neuropsychiatric diseases.
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