Lateralization of face processing in the human brain

Are visual face processing mechanisms the same in the left and right cerebral hemispheres? The possibility of such ‘duplicated processing’ seems puzzling in terms of neural resource usage, and we currently lack a precise characterization of the lateral differences in face processing. To address this need, we have undertaken a three-pronged approach. Using functional magnetic resonance imaging, we assessed cortical sensitivity to facial semblance, the modulatory effects of context and temporal response dynamics. Results on all three fronts revealed systematic hemispheric differences. We found that: (i) activation patterns in the left fusiform gyrus correlate with image-level face-semblance, while those in the right correlate with categorical face/non-face judgements. (ii) Context exerts significant excitatory/inhibitory influence in the left, but has limited effect on the right. (iii) Face-selectivity persists in the right even after activity on the left has returned to baseline. These results provide important clues regarding the functional architecture of face processing, suggesting that the left hemisphere is involved in processing ‘low-level’ face semblance, and perhaps is a precursor to categorical ‘deep’ analyses on the right.

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Hemispheric Differences in the Relationship Between Corticomotor Excitability Changes Following a Fine-Motor Task and Motor Learning

Journal of Neurophysiology ◽

10.1152/jn.00595.2003 ◽

2004 ◽

Vol 91 (4) ◽

pp. 1570-1578 ◽

Cited By ~ 100

Author(s):

Michael I. Garry ◽

Gary Kamen ◽

Michael A. Nordstrom

Keyword(s):

Motor Learning ◽

Motor Performance ◽

Fine Motor ◽

Hemispheric Differences ◽

Corticomotor Excitability ◽

Hand Muscles ◽

Right Hand ◽

Left And Right ◽

The Right ◽

Intrinsic Hand Muscles

Motor performance induces a postexercise increase in corticomotor excitability that may be associated with motor learning. We investigated whether there are hemispheric differences in the extent and/or time course of changes in corticomotor excitability following a manipulation task (Purdue pegboard) and their relationship with motor performance. Single- and paired-pulse (3 ms) transcranial magnetic stimulation (TMS) was used to assess task-induced facilitation of the muscle evoked potential (MEP) and intracortical inhibition (ICI) for three intrinsic hand muscles acting on digits 1, 2, and 5. Fifteen right-handed subjects performed three 30-s pegboard trials with left or right hand in separate sessions. TMS was applied to contralateral motor cortex before and after performance. Number of pegs placed was higher with the right hand, and performance improved (motor learning) with both hands over the three trials. MEP facilitation following performance was short-lasting (<15 min), selective for muscles engaged in gripping the pegs, and of similar magnitude in left and right hands. ICI was reduced immediately following performance with the right hand, but not the left. The extent of MEP facilitation was positively correlated with motor learning for the right hand only. We conclude that the pegboard task induces a selective, short-lasting change in excitability of corticospinal neurons controlling intrinsic hand muscles engaged in the task. Only left hemisphere changes were related to motor learning. This asymmetry may reflect different behavioral strategies for performance improvement with left and right upper limb in this task or hemispheric differences in the control of skilled hand movements.

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The rodent hippocampus as a bilateral structure: A review of hemispheric lateralization

10.1101/150193 ◽

2017 ◽

Cited By ~ 2

Author(s):

Jake T. Jordan

Keyword(s):

Brain Region ◽

Spatial Information ◽

Right Hemisphere ◽

Neural Substrates ◽

Hemispheric Lateralization ◽

Hemispheric Differences ◽

Functional Lateralization ◽

Left And Right ◽

The Right ◽

Behavior And Cognition

AbstractThe left and right rodent hippocampi exhibit striking lateralization in some of the very neural substrates considered to be critical for hippocampal cognitive function. Despite this, there is an overwhelming lack of consideration for hemispheric differences in studies of the rodent hippocampus. Asymmetries identified so far suggest that a bilateral model of the hippocampus will be essential for an understanding of this brain region, and perhaps of the brain more widely. Although hypotheses have been proposed to explain how the left and right hippocampi contribute to behavior and cognition, these hypotheses have either been refuted by more recent studies or have been limited in the scope of data they explain. Here, I will first review data on human and rodent hippocampal lateralization. The implications of these data suggest that considering the hippocampus as a bilateral structure with functional lateralization will be critical moving forward in understanding the function and mechanisms of this brain region. In exploring these implications, I will then propose a hypothesis of the hippocampus as a bilateral structure. This discrete-continuous (DC) hypothesis proposes that the left and right hippocampi contribute to spatial memory and navigation in a complementary manner. Specifically, the left hemisphere stores spatial information as discrete, salient locations and that the right hemisphere represents space continuously, contributing to route computation and flexible spatial navigation. Consideration of hippocampal lateralization in designing future studies may provide insight into the function of the hippocampus and resolve debates concerning its function.

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Processing of Words and Faces by Patients with Left and Right Temporal Lobe Epilepsy

Behavioural Neurology ◽

10.1155/1991/123767 ◽

1991 ◽

Vol 4 (2) ◽

pp. 121-128 ◽

Cited By ~ 12

Author(s):

Andrew W. Ellis ◽

Jonathan C. Hillam ◽

Alistair Cardno ◽

Janice Kay

Keyword(s):

Temporal Lobe ◽

Face Processing ◽

Reading Tests ◽

Temporal Lobes ◽

Control Subjects ◽

Significant Difference ◽

Left And Right ◽

Right Temporal Lobe Epilepsy ◽

The Right

Tests of word and face processing were given to patients with complex partial epilepsy focussed on the left or right temporal lobe, and to non-epileptic control subjects. The left TLE group showed the greatest impairment on object naming and on reading tests, but the right TLE group also showed a lesser impairment relative to the normal control subjects on both tests. The right TLE group was selectively impaired on distinguishing famous from non-famous faces while the left TLE group was impaired at naming famous faces they had successfully recognized as familiar. There was no significant difference between the three groups on recognition memory for words. The implications of the results for theories of the role of the temporal lobes in word and face processing, and the possible neural mechanisms responsible for the deficits in TLE patients, are discussed.

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Semantic Networks in the Divided Cerebral Hemispheres

Psychological Science ◽

10.1111/j.1467-9280.1995.tb00595.x ◽

1995 ◽

Vol 6 (4) ◽

pp. 212-218 ◽

Cited By ~ 3

Author(s):

Alice Cronin-Golomb

Keyword(s):

Right Hemisphere ◽

Semantic Networks ◽

Size Composition ◽

Strongly Correlated ◽

Hemispheric Differences ◽

Semantic Organization ◽

Left And Right ◽

The Right ◽

Or Organization ◽

Visual Hemifields

Hemispheric differences in the recognition and manipulation of meaning may be based on distinctions in size, composition, or organization of the right and left semantic networks The present study describes these features of pictorially based semantic networks in 3 subjects with complete forebrain commissurotomy Stimuli were presented for prolonged viewing to the left and right visual hemifields For each trial, the subjects chose from a 20-choice array all pictures that were associated with a target, then indicated the member of each pair of chosen associates that was more closely related to the target The hemispheres' networks were found to be of similar size and composition, but were organized differently The right hemisphere more often produced linear rankings of semantic associates to a target than did the left, and rankings by the two hemispheres were not strongly correlated Hemispheric differences in semantic organization mirror differences in perceptual organization, with the right hemisphere specialized for conventional meaning and the left hemisphere specialized for detecting and processing deviations from standard meaning

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Selective Attention to Faces in a Rapid Visual Stream: Hemispheric Differences in Enhancement and Suppression of Category-selective Neural Activity

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01220 ◽

2018 ◽

Vol 30 (3) ◽

pp. 393-410 ◽

Cited By ~ 7

Author(s):

Genevieve Quek ◽

Dan Nemrodov ◽

Bruno Rossion ◽

Joan Liu-Shuang

Keyword(s):

Selective Attention ◽

Left Hemisphere ◽

Right Hemisphere ◽

Hemispheric Differences ◽

Face Categorization ◽

The Face ◽

Left And Right ◽

The Right ◽

The Impact ◽

Selective Activity

In daily life, efficient perceptual categorization of faces occurs in dynamic and highly complex visual environments. Yet the role of selective attention in guiding face categorization has predominantly been studied under sparse and static viewing conditions, with little focus on disentangling the impact of attentional enhancement and suppression. Here we show that attentional enhancement and suppression exert a differential impact on face categorization supported by the left and right hemispheres. We recorded 128-channel EEG while participants viewed a 6-Hz stream of object images (buildings, animals, objects, etc.) with a face image embedded as every fifth image (i.e., OOOOFOOOOFOOOOF…). We isolated face-selective activity by measuring the response at the face presentation frequency (i.e., 6 Hz/5 = 1.2 Hz) under three conditions: Attend Faces, in which participants monitored the sequence for instances of female faces; Attend Objects, in which they responded to instances of guitars; and Baseline, in which they performed an orthogonal task on the central fixation cross. During the orthogonal task, face-specific activity was predominantly centered over the right occipitotemporal region. Actively attending to faces enhanced face-selective activity much more evidently in the left hemisphere than in the right, whereas attending to objects suppressed the face-selective response in both hemispheres to a comparable extent. In addition, the time courses of attentional enhancement and suppression did not overlap. These results suggest the left and right hemispheres support face-selective processing in distinct ways—where the right hemisphere is mandatorily engaged by faces and the left hemisphere is more flexibly recruited to serve current tasks demands.

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Sequent-systems for modal logic

Journal of Symbolic Logic ◽

10.2307/2273797 ◽

1985 ◽

Vol 50 (1) ◽

pp. 149-168 ◽

Cited By ~ 29

Author(s):

Kosta Došen

Keyword(s):

Order Logic ◽

Philosophical Logic ◽

Logical Constants ◽

First Order ◽

Sequent Systems ◽

Left And Right ◽

Level 1 ◽

The Right ◽

Level 2

AbstractThe purpose of this work is to present Gentzen-style formulations of S5 and S4 based on sequents of higher levels. Sequents of level 1 are like ordinary sequents, sequents of level 2 have collections of sequents of level 1 on the left and right of the turnstile, etc. Rules for modal constants involve sequents of level 2, whereas rules for customary logical constants of first-order logic with identity involve only sequents of level 1. A restriction on Thinning on the right of level 2, which when applied to Thinning on the right of level 1 produces intuitionistic out of classical logic (without changing anything else), produces S4 out of S5 (without changing anything else).This characterization of modal constants with sequents of level 2 is unique in the following sense. If constants which differ only graphically are given a formally identical characterization, they can be shown inter-replaceable (not only uniformly) with the original constants salva provability. Customary characterizations of modal constants with sequents of level 1, as well as characterizations in Hilbert-style axiomatizations, are not unique in this sense. This parallels the case with implication, which is not uniquely characterized in Hilbert-style axiomatizations, but can be uniquely characterized with sequents of level 1.These results bear upon theories of philosophical logic which attempt to characterize logical constants syntactically. They also provide an illustration of how alternative logics differ only in their structural rules, whereas their rules for logical constants are identical.

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Extinguishing Extinction: Hemispheric Differences in the Modulation of TMS-induced Visual Extinction by Directing Covert Spatial Attention

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00179 ◽

2012 ◽

Vol 24 (4) ◽

pp. 809-818 ◽

Cited By ~ 10

Author(s):

Nina Bien ◽

Rainer Goebel ◽

Alexander T. Sack

Keyword(s):

Spatial Attention ◽

Cognitive Neuroscience ◽

Early Stage ◽

Hemispheric Lateralization ◽

Hemispheric Differences ◽

Behavioral Deficits ◽

Stage Of Development ◽

Great Relevance ◽

Left And Right ◽

The Right

The topic of spatial attention is of great relevance for researchers in various fields, including neuropsychology, cognitive neuroscience, and cognitive psychology, as well as for clinical practice. Deficits of spatial attentional arising from parietal brain damage remain largely confined to the left visual field. The mechanisms underlying this hemispheric asymmetry are still elusive. We mimicked the neuropsychological syndrome of contralesional extinction by temporarily inducing a spatial attentional bias in healthy volunteers with TMS. We investigated whether directing covert spatial attention could enhance or, more importantly, counteract the resulting behavioral deficits. Although both the left and right parietal TMS induced contralateral extinction, only left hemifield extinction following right parietal TMS was severely aggravated by a competing stimulus in the ipsilesional (right) hemifield. We put forward the hypothesis that an asymmetry with respect to the ability of detaching attention from a distractor is contributing to the right hemispheric lateralization with regard to extinction. On a broader level, we suggest that “virtual patients” might be used for evaluating neuropsychological treatment in an early stage of development, reducing the burden on actual patients.

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Localization theorems for matrices and bounds for the zeros of polynomials over quaternion division algebra

Filomat ◽

10.2298/fil1802553a ◽

2018 ◽

Vol 32 (2) ◽

pp. 553-573 ◽

Cited By ~ 2

Author(s):

Sk. Ahmad ◽

Istkhar Ali

Keyword(s):

Zeros Of Polynomials ◽

Sufficient Condition ◽

Complex Matrix ◽

Quaternionic Matrix ◽

Left And Right ◽

The Stability ◽

The Right ◽

Left And Right Eigenvalues ◽

Quaternionic Polynomials

In this paper, we derive Ostrowski and Brauer type theorems for the left and right eigenvalues of a quaternionic matrix. Generalizations of Gerschgorin type theorems are discussed for the left and the right eigenvalues of a quaternionic matrix. After that, a sufficient condition for the stability of a quaternionic matrix is given that generalizes the stability condition for a complex matrix. Finally, a characterization of bounds is derived for the zeros of quaternionic polynomials.

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Investigating the influence of autism spectrum traits on face processing mechanisms in developmental prosopagnosia

10.31234/osf.io/kvxeb ◽

2021 ◽

Author(s):

Regan Fry ◽

Xian Li ◽

Travis Clark Evans ◽

Michael Esterman ◽

Jim Tanaka ◽

...

Keyword(s):

Face Processing ◽

Resting State ◽

Network Connectivity ◽

Resting State Fmri ◽

Superior Temporal Sulcus ◽

Autism Spectrum ◽

Autism Traits ◽

Face Selectivity ◽

Processing Mechanisms ◽

Posterior Superior Temporal Sulcus

Autism traits are commonly used as exclusionary criteria in studies of developmental prosopagnosia (DP). We investigated whether autism traits result in qualitatively different face processing in 43 DPs with high vs. low autism quotient (AQ) scores and 27 controls. Compared to controls, behavioral face recognition deficits were similar between the high and low AQ DP groups aside from worse emotion recognition in the high AQ DPs. Both DP groups showed reduced face selectivity in task-based fMRI, although higher AQ DPs showed decreased face selectivity in the posterior superior temporal sulcus. Resting-state fMRI showed similar face network connectivity between DP groups. This suggests that face processing is similar between the DP groups, with additional emotion processing deficits in higher AQ DPs.

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Separable Mechanisms in Face Processing: Evidence from Hemispheric Specialization

Journal of Cognitive Neuroscience ◽

10.1162/jocn.1991.3.1.42 ◽

1991 ◽

Vol 3 (1) ◽

pp. 42-58 ◽

Cited By ~ 136

Author(s):

Lynn A. Hillger ◽

Olivier Koenig

Keyword(s):

Left Hemisphere ◽

Face Processing ◽

Visual Processing ◽

Right Hemisphere ◽

Hemispheric Specialization ◽

Facial Feature ◽

General Purpose ◽

Facial Features ◽

Left And Right ◽

The Right

This article addresses three issues in face processing: First, is face processing primarily accomplished by the right hemisphere, or do both left- and right-hemisphere mechanisms play important roles? Second, are the mechanisms the same as those involved in general visual processing, or are they dedicated to face processing? Third, how can the mechanisms be characterized more precisely in terms of processes such as visual parsing? We explored these issues using the divided visual field methodology in four experiments. Experiments 1 and 2 provided evidence that both left- and right-hemisphere mechanisms are involved in face processing. In Experiment 1, a right-hemisphere advantage was found for both Same and Different trials when Same faces were identical and Different faces differed on all three internal facial features. Experiment 2 replicated the right-hemisphere advantage for Same trials but showed a left-hemisphere advantage for Different trials when one of three facial features differed between the target and the probe faces. Experiment 3 showed that the right-hemisphere advantage obtained with upright faces in Experiment 2 disappeared when the faces were inverted. This result suggests that there are right-hemisphere mechanisms specialized for processing upright faces, although it could not be determined whether these mechanisms are completely face-specific. Experiment 3 also provided evidence that the left-hemisphere mechanisms utilized in face processing tasks are general-purpose visual mechanisms not restricted to particular classes of visual stimuli. In Experiment 4, a left-hemisphere advantage was obtained when the task was to find one facial feature that was the same between the target and the probe faces. We suggest that left-hemisphere advantages shown in face processing are due to the parsing and analysis of the local elements of a face.

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