scholarly journals A thalamo-centric neural signature for restructuring negative self-beliefs

2022 ◽  
Author(s):  
Trevor Steward ◽  
Po-Han Kung ◽  
Christopher G. Davey ◽  
Bradford A. Moffat ◽  
Rebecca K. Glarin ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Emotional Reactivity ◽  
Effective Connectivity ◽  
Cognitive Restructuring ◽  
7 Tesla ◽  
Excitatory Effect ◽  
Negative Beliefs ◽  
Socratic Questioning ◽  
Major Shift ◽  
Cortical Regions

AbstractNegative self-beliefs are a core feature of psychopathology. Despite this, we have a limited understanding of the brain mechanisms by which negative self-beliefs are cognitively restructured. Using a novel paradigm, we had participants use Socratic questioning techniques to restructure negative beliefs during ultra-high resolution 7-Tesla functional magnetic resonance imaging (UHF 7 T fMRI) scanning. Cognitive restructuring elicited prominent activation in a fronto-striato-thalamic circuit, including the mediodorsal thalamus (MD), a group of deep subcortical nuclei believed to synchronize and integrate prefrontal cortex activity, but which has seldom been directly examined with fMRI due to its small size. Increased activity was also identified in the medial prefrontal cortex (MPFC), a region consistently activated by internally focused mental processing, as well as in lateral prefrontal regions associated with regulating emotional reactivity. Using Dynamic Causal Modelling (DCM), evidence was found to support the MD as having a strong excitatory effect on the activity of regions within the broader network mediating cognitive restructuring. Moreover, the degree to which participants modulated MPFC-to-MD effective connectivity during cognitive restructuring predicted their individual tendency to engage in repetitive negative thinking. Our findings represent a major shift from a cortico-centric framework of cognition and provide important mechanistic insights into how the MD facilitates key processes in cognitive interventions for common psychiatric disorders. In addition to relaying integrative information across basal ganglia and the cortex, we propose a multifaceted role for the MD whose broad excitatory pathways act to increase synchrony between cortical regions to sustain complex mental representations, including the self.

scholarly journals A thalamo-centric neural signature for restructuring negative self-beliefs

2021 ◽  
Author(s):  
Trevor Steward ◽  
Po-Han Kung ◽  
Christopher G. Davey ◽  
Bradford A. Moffat ◽  
Rebecca K. Glarin ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Emotional Reactivity ◽  
Effective Connectivity ◽  
Cognitive Restructuring ◽  
7 Tesla ◽  
Excitatory Effect ◽  
Socratic Questioning ◽  
Questioning Techniques ◽  
Major Shift ◽  
Cortical Regions

AbstractNegative self-beliefs are a core feature of psychopathology. Despite this, we have a limited understanding of the brain mechanisms by which negative self-beliefs are cognitively restructured. Using a novel paradigm, we had participants use Socratic questioning techniques to restructure self-beliefs during ultra-high resolution 7-Tesla functional magnetic resonance imaging (UHF fMRI) scanning. Cognitive restructuring elicited prominent activation in a fronto-striato-thalamic circuit, including the mediodorsal thalamus (MD), a group of deep subcortical nuclei believed to synchronize and integrate prefrontal cortex activity, but which has seldom been directly examined with fMRI due to its small size. Increased activity was also identified in the medial prefrontal cortex (MPFC), a region consistently activated by internally focused mental processing, as well as in lateral prefrontal regions associated with regulating emotional reactivity. Using Dynamic Causal Modelling (DCM), evidence was found to support the MD as having a strong excitatory effect on the activity of regions within the broader network mediating cognitive restructuring. Moreover, the degree to which participants modulated MPFC-to-MD effective connectivity during cognitive restructuring predicted their individual tendency to engage in repetitive negative thinking. Our findings represent a major shift from a cortico-centric framework of cognition and provide important mechanistic insights into how the MD facilitates key processes in cognitive interventions for common psychiatric disorders. In addition to relaying integrative information across basal ganglia and the cortex, we propose a multifaceted role for the MD whose broad excitatory pathways act to increase synchrony between cortical regions to sustain complex mental representations, including the self.

scholarly journals The Role of Primate Prefrontal Cortex in Bias and Shift Between Visual Dimensions

2019 ◽  
Vol 30 (1) ◽  
pp. 85-99 ◽  
Author(s):  
Farshad A Mansouri ◽  
Mark J Buckley ◽  
Daniel J Fehring ◽  
Keiji Tanaka
Keyword(s):  
Prefrontal Cortex ◽  
Anterior Cingulate ◽  
Top Down ◽  
Attentional Processes ◽  
Prefrontal Cortical ◽  
Frontopolar Cortex ◽  
Dorsolateral Prefrontal ◽  
Cortical Regions ◽  
Visual Cortical ◽  
Bilateral Lesions

Abstract Imaging and neural activity recording studies have shown activation in the primate prefrontal cortex when shifting attention between visual dimensions is necessary to achieve goals. A fundamental unanswered question is whether representations of these dimensions emerge from top-down attentional processes mediated by prefrontal regions or from bottom-up processes within visual cortical regions. We hypothesized a causative link between prefrontal cortical regions and dimension-based behavior. In large cohorts of humans and macaque monkeys, performing the same attention shifting task, we found that both species successfully shifted between visual dimensions, but both species also showed a significant behavioral advantage/bias to a particular dimension; however, these biases were in opposite directions in humans (bias to color) versus monkeys (bias to shape). Monkeys’ bias remained after selective bilateral lesions within the anterior cingulate cortex (ACC), frontopolar cortex, dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex (OFC), or superior, lateral prefrontal cortex. However, lesions within certain regions (ACC, DLPFC, or OFC) impaired monkeys’ ability to shift between these dimensions. We conclude that goal-directed processing of a particular dimension for the executive control of behavior depends on the integrity of prefrontal cortex; however, representation of competing dimensions and bias toward them does not depend on top-down prefrontal-mediated processes.

In Vivo Effective Connectivity Between Mouse Ventral Hippocampal Projections and Medial Prefrontal Cortex Microcircuits

2021 ◽  
Vol 89 (9) ◽  
pp. S121-S122
Author(s):  
David Kupferschmidt ◽  
Thomas Clarity ◽  
Rachel Mikofsky ◽  
Kirsten Gilchrist ◽  
Maxym Myroshnychenko ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Effective Connectivity

scholarly journals Intolerance of uncertainty is associated with heightened responding in the prefrontal cortex during instructed threat of shock

2020 ◽  
Author(s):  
Jayne Morriss ◽  
Tiffany Bell ◽  
Nicolò Biagi ◽  
Tom Johnstone ◽  
Carien M. van Reekum
Keyword(s):  
Prefrontal Cortex ◽  
Anxiety Disorder ◽  
Intolerance Of Uncertainty ◽  
Neural Circuitry ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Prefrontal Cortical ◽  
Cortical Regions ◽  
Rostral Prefrontal Cortex ◽  
Threat Of Shock

AbstractHeightened responding to uncertain threat is associated with anxiety disorder pathology. Here, we sought to determine if individual differences in self-reported intolerance of uncertainty (IU) underlie differential recruitment of neural circuitry during instructed threat of shock (n = 42). During the task, cues signalled uncertain threat of shock (50%) or certain safety from shock. Ratings, skin conductance and functional magnetic resonance imaging was acquired. Overall, participants displayed greater amygdala activation to uncertain threat vs. safe cues, in the absence of an effect of IU. However, we found that high was associated with greater activity in the medial prefrontal cortex and dorsomedial rostral prefrontal cortex to uncertain threat vs safe cues. These findings suggest that, during instructed threat of shock, IU is specifically related, over trait anxiety, to activation in prefrontal cortical regions. Taken together, these findings highlight the potential of self-reported IU in identifying mechanisms that may be related to conscious threat appraisal and anxiety disorder pathology.

scholarly journals Training neural networks to recognize speech increased their correspondence to the human auditory pathway but did not yield a shared hierarchy of acoustic features

2021 ◽  
Author(s):  
Jessica A.F. Thompson ◽  
Yoshua Bengio ◽  
Elia Formisano ◽  
Marc Schönwiesner
Keyword(s):  
Neural Networks ◽  
Recognition Task ◽  
Single Layer ◽  
Auditory Pathway ◽  
7 Tesla ◽  
List Type ◽  
Acoustic Features ◽  
Visual Areas ◽  
Cortical Regions ◽  
Fully Connected

AbstractThe correspondence between the activity of artificial neurons in convolutional neural networks (CNNs) trained to recognize objects in images and neural activity collected throughout the primate visual system has been well documented. Shallower layers of CNNs are typically more similar to early visual areas and deeper layers tend to be more similar to later visual areas, providing evidence for a shared representational hierarchy. This phenomenon has not been thoroughly studied in the auditory domain. Here, we compared the representations of CNNs trained to recognize speech (triphone recognition) to 7-Tesla fMRI activity collected throughout the human auditory pathway, including subcortical and cortical regions, while participants listened to speech. We found no evidence for a shared representational hierarchy of acoustic speech features. Instead, all auditory regions of interest were most similar to a single layer of the CNNs: the first fully-connected layer. This layer sits at the boundary between the relatively task-general intermediate layers and the highly task-specific final layers. This suggests that alternative architectural designs and/or training objectives may be needed to achieve fine-grained layer-wise correspondence with the human auditory pathway.HighlightsTrained CNNs more similar to auditory fMRI activity than untrainedNo evidence of a shared representational hierarchy for acoustic featuresAll ROIs were most similar to the first fully-connected layerCNN performance on speech recognition task positively associated with fmri similarity

scholarly journals Interacting roles of lateral and medial Orbitofrontal cortex in decision-making and learning : A system-level computational model

2019 ◽  
Author(s):  
Bhargav Teja Nallapu ◽  
Frédéric Alexandre
Keyword(s):  
Decision Making ◽  
Prefrontal Cortex ◽  
Computational Model ◽  
Orbitofrontal Cortex ◽  
Temporal Dynamics ◽  
System Level ◽  
Interacting Networks ◽  
Cortical Regions ◽  
Experimental Findings

AbstractIn the context of flexible and adaptive animal behavior, the orbitofrontal cortex (OFC) is found to be one of the crucial regions in the prefrontal cortex (PFC) influencing the downstream processes of decision-making and learning in the sub-cortical regions. Although OFC has been implicated to be important in a variety of related behavioral processes, the exact mechanisms are unclear, through which the OFC encodes or processes information related to decision-making and learning. Here, we propose a systems-level view of the OFC, positioning it at the nexus of sub-cortical systems and other prefrontal regions. Particularly we focus on one of the most recent implications of neuroscientific evidences regarding the OFC - possible functional dissociation between two of its sub-regions : lateral and medial. We present a system-level computational model of decision-making and learning involving the two sub-regions taking into account their individual roles as commonly implicated in neuroscientific studies. We emphasize on the role of the interactions between the sub-regions within the OFC as well as the role of other sub-cortical structures which form a network with them. We leverage well-known computational architecture of thalamo-cortical basal ganglia loops, accounting for recent experimental findings on monkeys with lateral and medial OFC lesions, performing a 3-arm bandit task. First we replicate the seemingly dissociate effects of lesions to lateral and medial OFC during decision-making as a function of value-difference of the presented options. Further we demonstrate and argue that such an effect is not necessarily due to the dissociate roles of both the subregions, but rather a result of complex temporal dynamics between the interacting networks in which they are involved.Author summaryWe first highlight the role of the Orbitofrontal Cortex (OFC) in value-based decision making and goal-directed behavior in primates. We establish the position of OFC at the intersection of cortical mechanisms and thalamo-basal ganglial circuits. In order to understand possible mechanisms through which the OFC exerts emotional control over behavior, among several other possibilities, we consider the case of dissociate roles of two of its topographical subregions - lateral and medial parts of OFC. We gather predominant roles of each of these sub-regions as suggested by numerous experimental evidences in the form of a system-level computational model that is based on existing neuronal architectures. We argue that besides possible dissociation, there could be possible interaction of these sub-regions within themselves and through other sub-cortical structures, in distinct mechanisms of choice and learning. The computational framework described accounts for experimental data and can be extended to more comprehensive detail of representations required to understand the processes of decision-making, learning and the role of OFC and subsequently the regions of prefrontal cortex in general.

Individual Differences in Mental Imagery Modulate Effective Connectivity of Scene-Selective Regions During Resting State

2021 ◽  
Author(s):  
Maria Giulia Tullo ◽  
Hannes Almgren ◽  
Frederik Van de Steen ◽  
Valentina Sulpizio ◽  
Daniele Marinazzo ◽  
...  
Keyword(s):  
Individual Differences ◽  
Mental Imagery ◽  
Resting State ◽  
Effective Connectivity ◽  
Relevant Information ◽  
Brain Regions ◽  
Intrinsic Activity ◽  
Inhibitory Influence ◽  
Cortical Regions ◽  
Intrinsic Fluctuation

Abstract Successful navigation relies on the ability to identify, perceive, and correctly process the spatial structure of a scene. It is well known that visual mental imagery plays a crucial role in navigation. Indeed, cortical regions encoding navigationally relevant information are also active during mental imagery of navigational scenes. However, it remains unknown whether their intrinsic activity and connectivity reflect the individuals’ ability to imagine a scene. Here, we primarily investigated the intrinsic causal interactions among scene-selective brain regions such as Parahipoccampal Place Area (PPA), Retrosplenial Complex (RSC), and Occipital Place Area (OPA) using Dynamic Causal Modelling (DCM) for resting-state functional magnetic resonance (rs-fMRI) data. Second, we tested whether resting-state effective connectivity parameters among scene-selective regions could reflect individual differences in mental imagery in our sample, as assessed by the self-reported Vividness of Visual Imagery Questionnaire (VVIQ). We found an inhibitory influence of occipito-medial on temporal regions, and an excitatory influence of more anterior on more medial and posterior brain regions. Moreover, we found that a key role in imagery is played by the connection strength from OPA to PPA, especially in the left hemisphere, since the influence of the signal between these scene-selective regions positively correlated with good mental imagery ability. Our investigation contributes to the understanding of the complexity of the causal interaction among brain regions involved in navigation and provides new insight in understanding how an essential ability, such as mental imagery, can be explained by the intrinsic fluctuation of brain signal.

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