Comparing Tactile Pattern and Vibrotactile Frequency Discrimination: A Human fMRI Study

2010 ◽  
Vol 103 (6) ◽  
pp. 3115-3122 ◽  
Author(s):  
Yiwen Li Hegner ◽  
Ying Lee ◽  
Wolfgang Grodd ◽  
Christoph Braun
Keyword(s):  
Time Course ◽  
Right Hemisphere ◽  
Temporal Frequency ◽  
Frequency Discrimination ◽  
Brain Regions ◽  
Anterior Insula ◽  
Cortical Areas ◽  
Tactile Stimuli ◽  
Spatio Temporal ◽  
The Right

We investigated to which extent the discrimination of tactile patterns and vibrotactile frequencies share common cortical areas. An adaptation paradigm has been used to identify cortical areas specific for processing particular features of tactile stimuli. Healthy right-handed subjects performed a delayed-match-to-sample (DMTS) task discriminating between pairs of tactile patterns or vibrotactile frequencies in separate functional MRI sessions. The tactile stimuli were presented to the right middle fingertip sequentially with a 5.5 s delay. Regions of interest (ROIs) were defined by cortical areas commonly activated in both tasks and those that showed differential activation between both tasks. Results showed recruitment of many common brain regions along the sensory motor pathway (such as bilateral somatosensory, premotor areas, and anterior insula) in both tasks. Three cortical areas, the right intraparietal sulcus (IPS), supramarginal gyrus (SMG)/parietal operculum (PO), and PO, were significantly more activated during the pattern than in the frequency task. Further BOLD time course analysis was performed in the ROIs. Significant BOLD adaptation was found in bilateral IPS, right anterior insula, and SMG/PO in the pattern task, whereas there was no significant BOLD adaptation found in the frequency task. In addition, the right hemisphere was found to be more dominant in the pattern than in the frequency task, which could be attributed to the differences between spatial (pattern) and temporal (frequency) processing. From the different spatio-temporal characteristics of BOLD activation in the pattern and frequency tasks, we concluded that different neuronal mechanisms are underlying the tactile spatial and temporal processing.

Engaging regularly with fiction influences connectivity in cortical areas for language and mentalizing

2017 ◽  
Author(s):  
Roel M. Willems ◽  
Franziska Hartung
Keyword(s):  
Functional Connectivity ◽  
Time Course ◽  
Language Skills ◽  
Brain Regions ◽  
Brain Areas ◽  
Daily Lives ◽  
Cortical Areas ◽  
Social Abilities ◽  
Behavioral Evidence ◽  
Amount Of Reading

Behavioral evidence suggests that engaging with fiction is positively correlated with social abilities. The rationale behind this link is that engaging with fictional narratives offers a ‘training modus’ for mentalizing and empathizing. We investigated the influence of the amount of reading that participants report doing in their daily lives, on connections between brain areas while they listened to literary narratives. Participants (N=57) listened to two literary narratives while brain activation was measured with fMRI. We computed time-course correlations between brain regions, and compared the correlation values from listening to narratives to listening to reversed speech. The between-region correlations were then related to the amount of fiction that participants read in their daily lives. Our results show that amount of fiction reading is related to functional connectivity in areas known to be involved in language and mentalizing. This suggests that reading fiction influences social cognition as well as language skills.

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.

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.

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.

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 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.

Visual Cortical Representation of Whole Words and Hemifield-split Word Parts

2016 ◽  
Vol 28 (2) ◽  
pp. 252-260 ◽  
Author(s):  
Lars Strother ◽  
Alexandra M. Coros ◽  
Tutis Vilis
Keyword(s):  
Visual Processing ◽  
Right Hemisphere ◽  
Visual Word ◽  
Anatomical Location ◽  
Word Form ◽  
Cortical Areas ◽  
Visual Hemifield ◽  
The Right ◽  
Visual Cortical ◽  
Form Information

Reading requires the neural integration of visual word form information that is split between our retinal hemifields. We examined multiple visual cortical areas involved in this process by measuring fMRI responses while observers viewed words that changed or repeated in one or both hemifields. We were specifically interested in identifying brain areas that exhibit decreased fMRI responses as a result of repeated versus changing visual word form information in each visual hemifield. Our method yielded highly significant effects of word repetition in a previously reported visual word form area (VWFA) in occipitotemporal cortex, which represents hemifield-split words as whole units. We also identified a more posterior occipital word form area (OWFA), which represents word form information in the right and left hemifields independently and is thus both functionally and anatomically distinct from the VWFA. Both the VWFA and the OWFA were left-lateralized in our study and strikingly symmetric in anatomical location relative to known face-selective visual cortical areas in the right hemisphere. Our findings are consistent with the observation that category-selective visual areas come in pairs and support the view that neural mechanisms in left visual cortex—especially those that evolved to support the visual processing of faces—are developmentally malleable and become incorporated into a left-lateralized visual word form network that supports rapid word recognition and reading.

scholarly journals Impaired Recognition of Emotional Faces after Stroke Involving Right Amygdala or Insula

2018 ◽  
Vol 39 (01) ◽  
pp. 087-100 ◽  
Author(s):  
Brittany Godin ◽  
Kumiko Oishi ◽  
Kenichi Oishi ◽  
Cameron Davis ◽  
Yessenia Gomez ◽  
...  
Keyword(s):  
Facial Expressions ◽  
Right Hemisphere ◽  
Anterior Insula ◽  
Human Anatomy ◽  
Lesion Volume ◽  
Stroke Patients ◽  
Emotional Faces ◽  
The Right ◽  
Right Hemisphere Stroke

AbstractDespite its basic and translational importance, the neural circuitry supporting the perception of emotional faces remains incompletely understood. Functional imaging studies and chronic lesion studies indicate distinct roles of the amygdala and insula in recognition of fear and disgust in facial expressions, whereas intracranial encephalography studies, which are not encumbered by variations in human anatomy, indicate a somewhat different role of these structures. In this article, we leveraged lesion-mapping techniques in individuals with acute right hemisphere stroke to investigate lesions associated with impaired recognition of prototypic emotional faces before significant neural reorganization can occur during recovery from stroke. Right hemisphere stroke patients were significantly less accurate than controls on a test of emotional facial recognition for both positive and negative emotions. Patients with right amygdala or anterior insula lesions had significantly lower scores than other right hemisphere stroke patients on recognition of angry and happy faces. Lesion volume within several regions, including the right amygdala and anterior insula, each independently contributed to the error rate in recognition of individual emotions. Results provide additional support for a necessary role of the right amygdala and anterior insula within a network of regions underlying recognition of facial expressions, particularly those that have biological importance or motivational relevance and have implications for clinical practice.

scholarly journals Dynamic Threat Processing

2019 ◽  
Vol 31 (4) ◽  
pp. 522-542 ◽  
Author(s):  
Christian Meyer ◽  
Srikanth Padmala ◽  
Luiz Pessoa
Keyword(s):  
Skin Conductance ◽  
Real Life ◽  
Brain Regions ◽  
Anterior Insula ◽  
Related Factors ◽  
Bed Nucleus ◽  
Context Sensitive ◽  
Threat Processing ◽  
Skin Conductance Responses ◽  
The Right

During real-life situations, multiple factors interact dynamically to determine threat level. In the current fMRI study involving healthy adult human volunteers, we investigated interactions between proximity, direction (approach vs. retreat), and speed during a dynamic threat-of-shock paradigm. As a measure of threat-evoked physiological arousal, skin conductance responses were recorded during fMRI scanning. Some brain regions tracked individual threat-related factors, and others were also sensitive to combinations of these variables. In particular, signals in the anterior insula tracked the interaction between proximity and direction where approach versus retreat responses were stronger when threat was closer compared with farther. A parallel proximity-by-direction interaction was also observed in physiological skin conductance responses. In the right amygdala, we observed a proximity by direction interaction, but intriguingly in the opposite direction as the anterior insula; retreat versus approach responses were stronger when threat was closer compared with farther. In the right bed nucleus of the stria terminalis, we observed an effect of threat proximity, whereas in the right periaqueductal gray/midbrain we observed an effect of threat direction and a proximity by direction by speed interaction (the latter was detected in exploratory analyses but not in a voxelwise fashion). Together, our study refines our understanding of the brain mechanisms involved during aversive anticipation in the human brain. Importantly, it emphasizes that threat processing should be understood in a manner that is both context-sensitive and dynamic.

Sign in / Sign up

Export Citation Format

Share Document