scholarly journals Brain Connectivity Analysis Under Semantic Vigilance and Enhanced Mental States

2019 ◽  
Vol 9 (12) ◽  
pp. 363 ◽  
Author(s):  
Fares Al-Shargie ◽  
Usman Tariq ◽  
Omnia Hassanin ◽  
Hasan Mir ◽  
Fabio Babiloni ◽  
...  
Keyword(s):  
Cognitive Processing ◽  
Right Hemisphere ◽  
Brain Connectivity ◽  
Vigilance Task ◽  
Mental States ◽  
Brain Regions ◽  
Emotional States ◽  
Processing Efficiency ◽  
Vigilance State ◽  
The Right

In this paper, we present a method to quantify the coupling between brain regions under vigilance and enhanced mental states by utilizing partial directed coherence (PDC) and graph theory analysis (GTA). The vigilance state is induced using a modified version of stroop color-word task (SCWT) while the enhancement state is based on audio stimulation with a pure tone of 250 Hz. The audio stimulation was presented to the right and left ears simultaneously for one-hour while participants perform the SCWT. The quantification of mental states was performed by means of statistical analysis of indexes based on GTA, behavioral responses of time-on-task (TOT), and Brunel Mood Scale (BRMUS). The results show that PDC is very sensitive to vigilance decrement and shows that the brain connectivity network is significantly reduced with increasing TOT, p < 0.05. Meanwhile, during the enhanced state, the connectivity network maintains high connectivity as time passes and shows significant improvements compared to vigilance state. The audio stimulation enhances the connectivity network over the frontal and parietal regions and the right hemisphere. The increase in the connectivity network correlates with individual differences in the magnitude of the vigilance enhancement assessed by response time to stimuli. Our results provide evidence for enhancement of cognitive processing efficiency with audio stimulation. The BRMUS was used to evaluate the emotional states of vigilance task before and after using the audio stimulation. BRMUS factors, such as fatigue, depression, and anger, significantly decrease in the enhancement group compared to vigilance group. On the other hand, happy and calmness factors increased with audio stimulation, p < 0.05.

scholarly journals Moral judgement by the disconnected left and right cerebral hemispheres: a split-brain investigation

2017 ◽  
Vol 4 (7) ◽  
pp. 170172 ◽  
Author(s):  
Conor M. Steckler ◽  
J. Kiley Hamlin ◽  
Michael B. Miller ◽  
Danielle King ◽  
Alan Kingstone
Keyword(s):  
Brain Research ◽  
Right Hemisphere ◽  
Mental States ◽  
Brain Regions ◽  
Moral Judgement ◽  
Temporoparietal Junction ◽  
Split Brain ◽  
Moral Judgements ◽  
The Right ◽  
Necessary And Sufficient

Owing to the hemispheric isolation resulting from a severed corpus callosum, research on split-brain patients can help elucidate the brain regions necessary and sufficient for moral judgement. Notably, typically developing adults heavily weight the intentions underlying others' moral actions, placing greater importance on valenced intentions versus outcomes when assigning praise and blame. Prioritization of intent in moral judgements may depend on neural activity in the right hemisphere's temporoparietal junction, an area implicated in reasoning about mental states. To date, split-brain research has found that the right hemisphere is necessary for intent-based moral judgement. When testing the left hemisphere using linguistically based moral vignettes, split-brain patients evaluate actions based on outcomes, not intentions. Because the right hemisphere has limited language ability relative to the left, and morality paradigms to date have involved significant linguistic demands, it is currently unknown whether the right hemisphere alone generates intent-based judgements. Here we use nonlinguistic morality plays with split-brain patient J.W. to examine the moral judgements of the disconnected right hemisphere, demonstrating a clear focus on intent. This finding indicates that the right hemisphere is not only necessary but also sufficient for intent-based moral judgement, advancing research into the neural systems supporting the moral sense.

scholarly journals Time Perception through the Processing of Verb Tenses: An ERP study regarding Mental Time Travel

2020 ◽  
Author(s):  
Charalabos Papageorgiou ◽  
Anastasios E. Giannopoulos ◽  
Athanasios S. Fokas ◽  
Paul M. Thompson ◽  
Nikolaos C. Kapsalis ◽  
...  
Keyword(s):  
Right Hemisphere ◽  
Brain Regions ◽  
Time Travel ◽  
Temporal Organization ◽  
Mental Time Travel ◽  
Precentral Gyrus ◽  
Alpha Oscillations ◽  
Biological Time ◽  
Underlying Mechanisms ◽  
The Right

ABSTRACTHumans are equipped with the so-called Mental Time Travel (MTT) ability, which allows them to consciously construct and elaborate past or future scenes. The mechanisms underlying MTT remain elusive. This study focused on the late positive potential (LPP) and alpha oscillations, considering that LPP covaries with the temporal continuity whereas the alpha oscillations index the temporal organization of perception. To that end, subjects were asked to focus on performing two mental functions engaging working memory, which involved mental self-projection into either the present-past (PP) border or the present-future (PF) border. To evaluate underlying mechanisms, the evoked frontal late positive potentials (LPP) as well as their cortical sources were analyzed via the standardized low-resolution brain electromagnetic tomography (sLORETA) technique. The LPP amplitudes - in the left lateral prefrontal areas that were elicited during PF tasks - were significantly higher than those associated with PP, whereas opposite patterns were observed in the central and right prefrontal areas. Crucially, the LPP activations of both the PP and PF self-projections overlapped with the brain’s default mode network and related interacting areas. Finally, we found enhanced alpha-related activation with respect to PP in comparison to PF, predominantly over the right hemisphere central brain regions (specifically, the precentral gyrus). These findings confirm that the two types of self-projection, as reflected by the frontally-distributed LPP, share common cortical resources that recruit different brain regions in a balanced way. This balanced distribution of brain activation might signify that biological time tends to behave in a homeostatic way.

The Structural Language Network

2017 ◽  
Author(s):  
Angela D. Friederici ◽  
Noam Chomsky
Keyword(s):  
White Matter ◽  
Language Processing ◽  
Sentence Processing ◽  
Information Transfer ◽  
Right Hemisphere ◽  
Brain Regions ◽  
Neural Basis ◽  
Fiber Tracts ◽  
White Matter Fiber Tracts ◽  
The Right

An adequate description of the neural basis of language processing must consider the entire network both with respect to its structural white matter connections and the functional connectivities between the different brain regions as the information has to be sent between different language-related regions distributed across the temporal and frontal cortex. This chapter discusses the white matter fiber bundles that connect the language-relevant regions. The chapter is broken into three sections. In the first, we look at the white matter fiber tracts connecting the language-relevant regions in the frontal and temporal cortices; in the second, the ventral and dorsal pathways in the right hemisphere that connect temporal and frontal regions; and finally in the third, the two syntax-relevant and (at least) one semantic-relevant neuroanatomically-defined networks that sentence processing is based on. From this discussion, it becomes clear that online language processing requires information transfer via the long-range white matter fiber pathways that connect the language-relevant brain regions within each hemisphere and between hemispheres.

scholarly journals Estimation of gender-specific connectional brain templates using joint multi-view cortical morphological network integration

2020 ◽  
Author(s):  
Nada Chaari ◽  
Hatice Camgöz Akdağ ◽  
Islem Rekik
Keyword(s):  
Right Hemisphere ◽  
Occipital Cortex ◽  
Brain Regions ◽  
Middle Temporal Gyrus ◽  
Network Clustering ◽  
Male And Female ◽  
Clustering Model ◽  
Net Method ◽  
The Right ◽  
Gender Specific

Abstract The estimation of a connectional brain template (CBT) integrating a population of brain networks while capturing shared and differential connectional patterns across individuals remains unexplored in gender fingerprinting. This paper presents the first study to estimate gender-specific CBTs using multi-view cortical morphological networks (CMNs) estimated from conventional T1-weighted magnetic resonance imaging (MRI). Specifically, each CMN view is derived from a specific cortical attribute (e.g. thickness), encoded in a network quantifying the dissimilarity in morphology between pairs of cortical brain regions. To this aim, we propose Multi-View Clustering and Fusion Network (MVCF-Net), a novel multi-view network fusion method, which can jointly identify consistent and differential clusters of multi-view datasets in order to capture simultaneously similar and distinct connectional traits of samples. Our MVCF-Net method estimates a representative and well-centered CBTs for male and female populations, independently, to eventually identify their fingerprinting regions of interest (ROIs) in four main steps. First, we perform multi-view network clustering model based on manifold optimization which groups CMNs into shared and differential clusters while preserving their alignment across views. Second, for each view, we linearly fuse CMNs belonging to each cluster, producing local CBTs. Third, for each cluster, we non-linearly integrate the local CBTs across views, producing a cluster-specific CBT. Finally, by linearly fusing the cluster-specific centers we estimate a final CBT of the input population. MVCF-Net produced the most centered and representative CBTs for male and female populations and identified the most discriminative ROIs marking gender differences. The most two gender-discriminative ROIs involved the lateral occipital cortex and pars opercularis in the left hemisphere and the middle temporal gyrus and lingual gyrus in the right hemisphere.

Neural Correlates of Mental State Decoding in Human Adults: An Event-related Potential Study

2004 ◽  
Vol 16 (3) ◽  
pp. 415-426 ◽  
Author(s):  
Mark A. Sabbagh ◽  
Margaret C. Moulson ◽  
Kate L. Harkness
Keyword(s):  
Theory Of Mind ◽  
Mental State ◽  
Right Hemisphere ◽  
Mental States ◽  
Neural Correlates ◽  
Event Related Potential ◽  
Neural Systems ◽  
Core Theory ◽  
Human Adults ◽  
The Right

Successful negotiation of human social interactions rests on having a theory of mind—an understanding of how others' behaviors can be understood in terms of internal mental states, such as beliefs, desires, intentions, and emotions. A core theory-of-mind skill is the ability to decode others' mental states on the basis of observable information, such as facial expressions. Although several recent studies have focused on the neural correlates of reasoning about mental states, no research has addressed the question of what neural systems underlie mental state decoding. We used dense-array eventrelated potentials (ERP) to show that decoding mental states from pictures of eyes is associated with an N270–400 component over inferior frontal and anterior temporal regions of the right hemisphere. Source estimation procedures suggest that orbitofrontal and medial temporal regions may underlie this ERP effect. These findings suggest that different components of everyday theory-of-mind skills may rely on dissociable neural mechanisms.

scholarly journals Gene expression profiling of the dorsolateral and medial orbitofrontal cortex in schizophrenia

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
Mihovil Mladinov ◽  
Goran Sedmak ◽  
Heidi R. Fuller ◽  
Mirjana Babić Leko ◽  
Davor Mayer ◽  
...  
Keyword(s):  
Gene Expression ◽  
Prefrontal Cortex ◽  
Cognitive Processing ◽  
Orbitofrontal Cortex ◽  
Right Hemisphere ◽  
Transcriptome Profiling ◽  
Differentially Expressed ◽  
Unknown Etiology ◽  
Dorsolateral Prefrontal ◽  
The Right

AbstractSchizophrenia is a complex polygenic disorder of unknown etiology. Over 3,000 candidate genes associated with schizophrenia have been reported, most of which being mentioned only once. Alterations in cognitive processing - working memory, metacognition and mentalization - represent a core feature of schizophrenia, which indicates the involvement of the prefrontal cortex in the pathophysiology of this disorder. Hence we compared the gene expression in postmortem tissue from the left and right dorsolateral prefrontal cortex (DLPFC, Brodmann's area 46), and the medial part of the orbitofrontal cortex (MOFC, Brodmann's area 11/12), in six patients with schizophrenia and six control brains. Although in the past decade several studies performed transcriptome profiling in schizophrenia, this is the first study to investigate both hemispheres, providing new knowledge about possible brain asymmetry at the level of gene expression and its relation to schizophrenia. We found that in the left hemisphere, twelve genes from the DLPFC and eight genes from the MOFC were differentially expressed in patients with schizophrenia compared to controls. In the right hemisphere there was only one gene differentially expressed in the MOFC. We reproduce the involvement of previously reported genes TARDBP and HNRNPC in the pathogenesis of schizophrenia, and report seven novel genes:

scholarly journals Asking ‘why?’ enhances theory of mind when evaluating harm but not purity violations

2019 ◽  
Vol 14 (7) ◽  
pp. 699-708 ◽  
Author(s):  
James A Dungan ◽  
Liane Young
Keyword(s):  
Theory Of Mind ◽  
Mental States ◽  
Brain Regions ◽  
Judgment Task ◽  
Moral Judgments ◽  
Moral Norms ◽  
Temporoparietal Junction ◽  
Task Instructions ◽  
Right Temporoparietal Junction ◽  
The Right

Abstract Recent work in psychology and neuroscience has revealed important differences in the cognitive processes underlying judgments of harm and purity violations. In particular, research has demonstrated that whether a violation was committed intentionally vs accidentally has a larger impact on moral judgments of harm violations (e.g. assault) than purity violations (e.g. incest). Here, we manipulate the instructions provided to participants for a moral judgment task to further probe the boundary conditions of this intent effect. Specifically, we instructed participants undergoing functional magnetic resonance imaging to attend to either a violator’s mental states (why they acted that way) or their low-level behavior (how they acted) before delivering moral judgments. Results revealed that task instructions enhanced rather than diminished differences between how harm and purity violations are processed in brain regions for mental state reasoning or theory of mind. In particular, activity in the right temporoparietal junction increased when participants were instructed to attend to why vs how a violator acted to a greater extent for harm than for purity violations. This result constrains the potential accounts of why intentions matter less for purity violations compared to harm violations and provide further insight into the differences between distinct moral norms.

Hemispheric Asymmetries in a Signal Detection Task

1983 ◽  
Vol 57 (3) ◽  
pp. 923-929 ◽  
Author(s):  
John L. Andreassi ◽  
Charles S. Rebert ◽  
Ferol F. Larsen
Keyword(s):  
Signal Detection ◽  
Right Hemisphere ◽  
Reaction Times ◽  
Vigilance Task ◽  
Verbal Stimulus ◽  
Right Visual Field ◽  
Left And Right ◽  
The Right ◽  
Male Subjects ◽  
Central Fixation

Reaction time and signal detection performance were measured during a 78-min. vigilance task. 12 right-handed male subjects served in two experimental sessions. Subjects focused on a central fixation point and responded to signals presented at unpredictable times in one of three locations: 2.5° to right of central fixation, central, and 2.5° to the left of center. Subjects decided whether to press a response key with either the left or right hand with each presentation. Over-all vigilance performance (signal detections and response time) was similar for left and right visual-field presentations. Evidence from reaction times indicated that responses controlled by the left hemisphere were faster to a verbal stimulus (T) while reactions controlled by the right hemisphere were faster to an apparent non-verbal stimulus, an inverted T.

Laterality of Lesions and Trait-Anxiety on Working Memory Performance

2002 ◽  
Vol 94 (2) ◽  
pp. 551-558 ◽  
Author(s):  
William D. S. Killgore
Keyword(s):  
Working Memory ◽  
Left Hemisphere ◽  
Cognitive Processing ◽  
Trait Anxiety ◽  
Right Hemisphere ◽  
Digit Span ◽  
Memory Performance ◽  
Brain Lesion ◽  
Cerebral Activation ◽  
The Right

An asymmetry of anterior cerebral activation favoring the right hemisphere has been associated with dispositional negative affect including trait-anxiety, while the opposite appears true of cerebral asymmetry favoring the left hemisphere. It was hypothesized that an asymmetry of cerebral activation, as defined by scores on a measure of trait-anxiety, ipsilateral to the side of an anterior brain lesion would be associated with less efficient cognitive processing than greater activation in the hemisphere contralateral to the lesion. Patients with anterior left ( n = 16) or right ( n = 15) hemisphere lesions completed the State-Trait Anxiety Inventory and several neurocognitive tasks. Of the abilities tested, only Digit Span scores showed an interaction between side of lesion and presumed activation asymmetry. Patients with right- but not with left-hemisphere damage showed significant differences in working memory performance depending on the presumed direction of asymmetry of the two hemispheres, supporting the dual roles of the right hemisphere in affective processing and directed attention.

scholarly journals Optical Mapping of Brain Activity Underlying Directionality and Its Modulation by Expertise in Mandarin/English Interpreting

2021 ◽  
Vol 15 ◽  
Author(s):  
Yan He ◽  
Yinying Hu ◽  
Yaxi Yang ◽  
Defeng Li ◽  
Yi Hu
Keyword(s):  
Prefrontal Cortex ◽  
Cognitive Skills ◽  
Near Infrared ◽  
Right Hemisphere ◽  
Brain Activity ◽  
Brain Regions ◽  
Broca’S Area ◽  
Broca's Area ◽  
Functional Near Infrared Spectroscopy ◽  
The Right

Recent neuroimaging research has suggested that unequal cognitive efforts exist between interpreting from language 1 (L1) to language 2 (L2) compared with interpreting from L2 to L1. However, the neural substrates that underlie this directionality effect are not yet well understood. Whether directionality is modulated by interpreting expertise also remains unknown. In this study, we recruited two groups of Mandarin (L1)/English (L2) bilingual speakers with varying levels of interpreting expertise and asked them to perform interpreting and reading tasks. Functional near-infrared spectroscopy (fNIRS) was used to collect cortical brain data for participants during each task, using 68 channels that covered the prefrontal cortex and the bilateral perisylvian regions. The interpreting-related neuroimaging data was normalized by using both L1 and L2 reading tasks, to control the function of reading and vocalization respectively. Our findings revealed the directionality effect in both groups, with forward interpreting (from L1 to L2) produced more pronounced brain activity, when normalized for reading. We also found that directionality was modulated by interpreting expertise in both normalizations. For the group with relatively high expertise, the activated brain regions included the right Broca’s area and the left premotor and supplementary motor cortex; whereas for the group with relatively low expertise, the activated brain areas covered the superior temporal gyrus, the dorsolateral prefrontal cortex (DLPFC), the Broca’s area, and visual area 3 in the right hemisphere. These findings indicated that interpreting expertise modulated brain activation, possibly because of more developed cognitive skills associated with executive functions in experienced interpreters.

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