Changes in functional connectivity between the left fusiform gyrus and the right hemisphere homologues of the orthographic processing network in acquired dysgraphia

Human kin recognition activates substrates of the extended facial processing network, notably the right-hemisphere structures involved in self-face recognition and posterior medial cortical substrates. To understand the mechanisms underlying prosociality toward kin faces in comparison to other familiar faces, we investigated the neural correlates of implicit trustworthiness ratings to faces of actual kin and personal friends, controlling for activation to distracter faces. When controlling for activation associated with unknown faces, trustworthiness ratings of faces of kin, compared to friends, were associated with increased activation in the dorsal anterior cingulate cortex, posterior cingulate, and precuneous. On the other hand, trustworthiness ratings of friend faces, relative to kin faces, were associated with the lateral occipital gyrus and insular cortex. Trustworthiness ratings for unknown faces were only associated with activation in the fusiform gyrus. These findings suggest that we should employ medial cortical substrates known to be part of the self-other network when making implicit social judgements about kin, but not other classes of facial stimuli.

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A Brain Mapping Approach to Inspect the Underlying Neural Correlates upon Perceiving Persian Metaphors

10.31235/osf.io/hbdsf ◽

2020 ◽

Author(s):

Elaheh Yazdani ◽

Amirsaeid Moloodi ◽

Zahra Kheradmand ◽

Ali Mohammad Kamali ◽

K.S. Rao ◽

...

Keyword(s):

Functional Connectivity ◽

Brain Mapping ◽

Semantic Processing ◽

Large Scale ◽

Figurative Language ◽

Right Hemisphere ◽

Mother Tongue ◽

Abstract Concepts ◽

Neural Modulation ◽

The Right

Metaphors are frequently used in our daily life communications to comprehend and convey abstract concepts. Different neuroimaging studies also show a wide neural connection to metaphor perception. This study used a brain mapping setup (quantitative electroencephalography) to examine large-scale brain networks in participants when they were submitted to non-metaphorical sentences as compared to creative and conventional metaphorical phrases. To this end, 20 healthy right-handed individuals with Persian as their mother-tongue language consented to participate in the above language task. Having evaluated the functional connectivity across key cortical hubs, no significant or predominant role of the right hemisphere was observed upon comprehension of the conventional and creative metaphorical phrases. Rather, a wide interhemispheric functional connectivity is proposed to play a key part in the above task. Further understanding about the neural networks involved in the semantic processing of metaphors may potentially open new avenues to neural modulation in patients who find it challenging to comprehend figurative language or abstract metaphorical meanings (e.g. schizophrenics).

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Functional cortico-subcortical reorganization after complete hemispheric disconnection for intractable epilepsy

10.1101/707539 ◽

2019 ◽

Author(s):

Thomas Blauwblomme ◽

Athena Demertzi ◽

Jean-Marc Tacchela ◽

Ludovic Fillon ◽

Marie Bourgeois ◽

...

Keyword(s):

Functional Connectivity ◽

Right Hemisphere ◽

Intractable Epilepsy ◽

Minimally Conscious State ◽

Conscious State ◽

Subcortical Structures ◽

Drug Resistant Epilepsy ◽

Classification Probability ◽

The Right ◽

Minimally Conscious

AbstractHemispherotomy is a treatment for drug-resistant epilepsy with the whole hemisphere involved in seizure onset. As recovery mechanisms are still debated, we characterize functional reorganization with multimodal MRI in two children operated on the right hemisphere (RH). We found that interhemispheric functional connectivity was abolished in both patients. The healthy left hemispheres (LH) displayed focal hyperperfusion in motor and limbic areas, and preserved network-level organization. The disconnected RHs were hypoperfused despite sustained network-level organization. Functional connectivity was increased in the left thalamo-cortical loop and between the cerebelli. The classification probability of the RH corresponding to a minimally conscious state was smaller than for the LH. We conclude that after hemispherotomy, neurological rehabilitation is sustained by cortical disinhibition and reinforcement of connectivity driven by subcortical structures in the remaining hemisphere. Our results highlight the effect of vascularization on functional connectivity and raise inquiries about the conscious state of the isolated hemisphere.

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Hemispheric Asymmetries for Whole-Based and Part-Based Face Processing in the Human Fusiform Gyrus

Journal of Cognitive Neuroscience ◽

10.1162/089892900562606 ◽

2000 ◽

Vol 12 (5) ◽

pp. 793-802 ◽

Cited By ~ 281

Author(s):

Bruno Rossion ◽

Laurence Dricot ◽

Anne Devolder ◽

Jean-Michel Bodart ◽

Marc Crommelinck ◽

...

Keyword(s):

Face Processing ◽

Right Hemisphere ◽

Fusiform Gyrus ◽

Homologous Region ◽

Double Dissociation ◽

Face Features ◽

Behavioral Studies ◽

Anatomical Localization ◽

The Right ◽

New Evidence

Behavioral studies indicate a right hemisphere advantage for processing a face as a whole and a left hemisphere superiority for processing based on face features. The present PET study identifies the anatomical localization of these effects in well-defined regions of the middle fusiform gyri of both hemispheres. The right middle fusiform gyrus, previously described as a face-specific region, was found to be more activated when matching whole faces than face parts whereas this pattern of activity was reversed in the left homologous region. These lateralized differences appeared to be specific to faces since control objects processed either as wholes or parts did not induce any change of activity within these regions. This double dissociation between two modes of face processing brings new evidence regarding the lateralized localization of face individualization mechanisms in the human brain.

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Learning to Read an Alphabet of Human Faces Produces Left-lateralized Training Effects in the Fusiform Gyrus

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00506 ◽

2014 ◽

Vol 26 (4) ◽

pp. 896-913 ◽

Cited By ~ 16

Author(s):

Michelle W. Moore ◽

Corrine Durisko ◽

Charles A. Perfetti ◽

Julie A. Fiez

Keyword(s):

Functional Neuroimaging ◽

Reading Performance ◽

Fusiform Gyrus ◽

Orthographic Processing ◽

Word Form ◽

Learning To Read ◽

Visual Word Form Area ◽

The Right ◽

Human Faces ◽

Language Areas

Numerous functional neuroimaging studies have shown that most orthographic stimuli, such as printed English words, produce a left-lateralized response within the fusiform gyrus (FG) at a characteristic location termed the visual word form area (VWFA). We developed an experimental alphabet (FaceFont) comprising 35 face–phoneme pairs to disentangle phonological and perceptual influences on the lateralization of orthographic processing within the FG. Using functional imaging, we found that a region in the vicinity of the VWFA responded to FaceFont words more strongly in trained versus untrained participants, whereas no differences were observed in the right FG. The trained response magnitudes in the left FG region correlated with behavioral reading performance, providing strong evidence that the neural tissue recruited by training supported the newly acquired reading skill. These results indicate that the left lateralization of the orthographic processing is not restricted to stimuli with particular visual-perceptual features. Instead, lateralization may occur because the anatomical projections in the vicinity of the VWFA provide a unique interconnection between the visual system and left-lateralized language areas involved in the representation of speech.

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Functional connectivity of dorsolateral prefrontal cortex predicts cocaine relapse

10.1101/2020.12.17.20245399 ◽

2020 ◽

Author(s):

Tianye Zhai ◽

Betty Jo Salmeron ◽

Hong Gu ◽

Bryon Adinoff ◽

Elliot A. Stein ◽

...

Keyword(s):

Prefrontal Cortex ◽

Functional Connectivity ◽

Dorsolateral Prefrontal Cortex ◽

Addiction Treatment ◽

Right Hemisphere ◽

Cox Regression ◽

Brain Regions ◽

Psychosocial Treatment ◽

Dorsolateral Prefrontal ◽

The Right

AbstractBackgroundRelapse is one of the most perplexing problems of addiction. The dorsolateral prefrontal cortex (DLPFC) is crucially involved in numerous cognitive and affective processes that are implicated in phenotypes of addiction, and is one of the most frequently reported brain regions with aberrant functionality in substance use disorders. However, the DLPFC is an anatomically large and functionally heterogeneous region, and the specific DLPFC-based circuits that contribute to drug relapse remain unknown.MethodsWe systematically investigated the relationship of cocaine relapse with 98 DLPFC functional circuits defined by evenly sampling the entire bilateral DLPFC in a cohort of cocaine dependent patients (n=43, 5F) following a psychosocial treatment intervention. A Cox regression model was utilized to predict relapse likelihood based on DLPFC functional connectivity strength.ResultsFunctional connectivity from 3 of the 98 DLPFC loci, one on the left and two on the right hemisphere, significantly predicted cocaine relapse with an accuracy of 83.9%, 84.7% and 85.4%, respectively. Combining all three significantly improved prediction validity to 87.5%. Protective and risk circuits related to these DLPFC loci were identified that are known to support “bottom up” drive to use drug and “top down” control over behavior together with social emotional, learning and memory processing.ConclusionThree DLPFC-centric circuits were identified that predict relapse to cocaine use with high accuracy. These functionally distinct DLPFC-based circuits provide insights into the multiple roles played by the DLPFC in cognitive and affective functioning that affects treatment outcome. The identified DLPFC loci may serve as potential neuromodulation targets for addiction treatment and as clinically relevant biomarkers of its efficacy.

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Disruption in Surface-Based Functional Connectivity in the Right Posterior Hippocampal CA3 Subfield: A Probable Neural Basis of Visuospatial Working Memory Impairment in Patients With Right Temporal Lobe Epilepsy

Frontiers in Neurology ◽

10.3389/fneur.2021.735689 ◽

2021 ◽

Vol 12 ◽

Author(s):

Zongxia Lv ◽

Zirong Chen ◽

Wei Ye ◽

Xiaomin Pang ◽

Liluo Nie ◽

...

Keyword(s):

Working Memory ◽

Functional Connectivity ◽

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Right Hemisphere ◽

Anterior Cingulate ◽

Visuospatial Working Memory ◽

Neural Basis ◽

Right Temporal Lobe Epilepsy ◽

The Right

Visuospatial working memory (VSWM) impairment is common in patients with right temporal lobe epilepsy (rTLE). The posterior hippocampus is critical for spatial memory, but the contributions of the different subfields to VSWM deficits remain unclear. Forty-six rTLE patients and 42 healthy controls (HCs) were recruited. Resting-state fMRI (rsfMRI) and structural MRI scans were administered, followed by a VSWM_Nback test. The right posterior hippocampus was automatically segmented, and the surface-based functional connectivity (SBFC) of the subiculum (Sub), CA1, CA3, dentate gyrus (DG), hippocampal tail, and right entorhinal cortex (EC) were compared between groups. Correlation analysis was performed between the altered SBFC and VSWM_Nback scores for rTLE patients. The results showed that rTLE patients underperformed in the VSWM_Nback test, with longer mean reaction time of accurate response (ACCmeanRT) in 0back and 2back condition, lower hit rate (HR) and higher false alarm rate (FAR) in 2back condition. Compared with HCs, the rCA3 in the rTLE group exhibited decreased SBFC with inferior parietal cortex (IPC), temporal lateral cortex (TLC), and posterior visual cortex (PVC) in the right hemisphere as well as the bilateral dorsolateral prefrontal cortex (DLPFC). The SBFC of the rEC and right anterior cingulate cortex (rACC) increased in the rTLE group. Within the rTLE group, the decreased SBFC of the rCA3-rIPC and rCA3-rLTC were correlated with worse VSWM performance. Therefore, the decreased SBFC of the rCA3-rIPC and rCA3-rLTC might be the critical aberrant FC pattern reflecting VSWM impairment in rTLE patients. The mechanism might involve functional disruption between the core subsystem and the medial temporal subsystem of the default mode network (DMN).

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Motor Symptom Lateralization Influences Cortico-Striatal Functional Connectivity in Parkinson's Disease

Frontiers in Neurology ◽

10.3389/fneur.2021.619631 ◽

2021 ◽

Vol 12 ◽

Author(s):

Wen Su ◽

Kai Li ◽

Chun-Mei Li ◽

Xin-Xin Ma ◽

Hong Zhao ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Functional Connectivity ◽

Orbitofrontal Cortex ◽

Resting State ◽

Right Hemisphere ◽

Motor Symptom ◽

Control Group ◽

Significant Difference ◽

The Right

Objective: The striatum is unevenly impaired bilaterally in Parkinson's disease (PD). Because the striatum plays a key role in cortico-striatal circuits, we assume that lateralization affects cortico-striatal functional connectivity in PD. The present study sought to evaluate the effect of lateralization on various cortico-striatal circuits through resting-state functional magnetic resonance imaging (fMRI).Methods: Thirty left-onset Parkinson's disease (LPD) patients, 27 right-onset Parkinson's disease (RPD) patients, and 32 normal controls with satisfactory data were recruited. Their demographic, clinical, and neuropsychological information was collected. Resting-state fMRI was performed, and functional connectivity changes of seven subdivisions of the striatum were explored in the two PD groups. In addition, the associations between altered functional connectivity and various clinical and neuropsychological characteristics were analyzed by Pearson's or Spearman's correlation.Results: Directly comparing the LPD and RPD patients demonstrated that the LPD patients had lower FC between the left dorsal rostral putamen and the left orbitofrontal cortex than the RPD patients. In addition, the LPD patients showed aberrant functional connectivity involving several striatal subdivisions in the right hemisphere. The right dorsal caudate, ventral rostral putamen, and superior ventral striatum had decreased functional connectivity with the cerebellum and parietal and occipital lobes relative to the normal control group. The comparison between RPD patients and the controls did not obtain significant difference in functional connectivity. The functional connectivity between the left dorsal rostral putamen and the left orbitofrontal cortex was associated with contralateral motor symptom severity in PD patients.Conclusions: Our findings provide new insights into the distinct characteristics of cortico-striatal circuits in LPD and RPD patients. Lateralization of motor symptoms is associated with lateralized striatal functional connectivity.

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