scholarly journals Dynamic interhemispheric coordination in face processing

2017 ◽  
Author(s):  
Zhengang Lu ◽  
Bingbing Guo ◽  
Ming Meng

AbstractOur conscious experience of the world is normally unified. The brain coordinates different processes from the left and right hemispheres into one experience. However, the neural mechanisms underlying interhemispheric coordination remain poorly understood. A mechanistic approach to understanding interhemispheric coordination is “communication through coherence” (Fries, 2005; 2015). Using a recently developed time-resolved psychophysics (Fiebelkorn, Saalmann, & Kastner, 2013; Landau & Fries, 2012; Song, Meng, Chen, Zhou, & Luo, 2014), combined with fMRI decoding method, we investigated the interhemispheric coordination through coherence, by focusing on a quintessential case of hemispheric lateralized brain function: face processing in the left and right fusiform face area (FFA). We observed coherent oscillatory fMRI multi-voxel patterns in the left and right FFA when two stimuli presented successively cross visual fields, either initiating coordination from the left hemisphere or right hemisphere. When interhemispheric coordination started from the dominant right hemisphere, a coherent 44° phase difference between the left and right FFA in 3-4 Hz was observed; whereas when interhemispheric coordination started from the non-dominant left hemisphere, a coherent −17° phase difference between the left and right FFA in 5.5-6.5 Hz was observed. These results suggest that different phase coherence might mediate the interhemispheric coordination of face perception, depending on whether the initiating hemisphere is dominant or non-dominant. Our findings provide compelling fMRI evidence for interhemispheric coordination through coherence. The time-resolved fMRI decoding approach would be a useful starting point for a more promising approach for future investigation in interhemispheric dynamic coordination with fine-grained spatial and temporal resolution.

1991 ◽  
Vol 3 (4) ◽  
pp. 313-321 ◽  
Author(s):  
Atsuko Nakagawa

The role of the left and right hemisphere was examined during semantic priming by antonyms, remote associates, and unrelated words. Targets presented directly to the left hemisphere showed an early facilitation and a late developing inhibition, while targets presented directly to the right hemisphere showed a late developing facilitation of strong and weak associations and little evidence of inhibition. When a visual cue was given prior to each target word, reaction times were facilitated equally in both visual fields and for all prime target relationships. When the priming task was combined with shadowing, reaction times generally increased and all evidence of inhibition in left hemisphere processing disappeared. This supported the idea that the inhibition found in the left hemisphere was due to its interaction with the anterior attention network.


1991 ◽  
Vol 3 (1) ◽  
pp. 42-58 ◽  
Author(s):  
Lynn A. Hillger ◽  
Olivier Koenig

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.


Neurology ◽  
1998 ◽  
Vol 51 (2) ◽  
pp. 458-464 ◽  
Author(s):  
D. Boatman ◽  
J. Hart ◽  
R. P. Lesser ◽  
N. Honeycutt ◽  
N. B. Anderson ◽  
...  

Objective: To investigate the right hemispheric speech perception capabilities of an adult right-handed patient with seizures.Methods: Consecutive, unilateral, intracarotid sodium amobarbital injections and left hemispheric electrical interference mapping were used to determine lateralization and localization of speech perception, measured as syllable discrimination.Results: Syllable discrimination remained intact after left and right intracarotid sodium amobarbital injections. Language otherwise strongly lateralized to the left hemisphere. Despite evidence of bilateral speech perception capabilities, electrical interference testing in the left posterior temporal lobe impaired syllable discrimination.Conclusions: The results suggest a functionally symmetric, parallel system in the adult brain with preferential use of left hemispheric pathways for speech perception.


1995 ◽  
Vol 6 (3) ◽  
pp. 157-164 ◽  
Author(s):  
Janet Metcalfe ◽  
Margaret Funnell ◽  
Michael S. Gazzaniga

Six experiments explored hemispheric memory differences in a patient who had undergone complete corpus callosum resection The right hemisphere was better able than the left to reject new events similar to originally presented materials of several types, including abstract visual forms, faces, and categorized lists of words Although the left hemisphere is capable of mental manipulation, imagination, semantic priming, and complex language production, these functions are apparently linked to memory confusions—confusions less apparent in the more literal right hemisphere Differences between the left and right hemispheres in memory for new schematically consistent or categorically related events may provide a source of information allowing people to distinguish between what they actually witnessed and what they only inferred


1984 ◽  
Vol 59 (3) ◽  
pp. 867-874 ◽  
Author(s):  
Ruth Nass

Recovery and neural reorganization after congenital left- and right-brain injury is assessed on dichotic listening and tachistoscopic visuo-perceptual tasks. A matched-pair approach for age and type of lesion is used. Over-all, deficits are less pronounced than in adults. Innate specialization of both left and right hemispheres is supported by the data. In addition, a left-right maturational gradient is suggested by the all-around better performance of the child with left-hemisphere pathology. The later maturing, relatively less-committed right hemisphere is better able to compensate after unilateral injury.


Perception ◽  
2021 ◽  
Vol 50 (1) ◽  
pp. 27-38
Author(s):  
Ella K. Moeck ◽  
Nicole A. Thomas ◽  
Melanie K. T. Takarangi

Attention is unequally distributed across the visual field. Due to greater right than left hemisphere activation for visuospatial attention, people attend slightly more to the left than the right side. As a result, people voluntarily remember visual stimuli better when it first appears in the left than the right visual field. But does this effect—termed a right hemisphere memory bias—also enhance involuntary memory? We manipulated the presentation location of 100 highly negative images (chosen to increase the likelihood that participants would experience any involuntary memories) in three conditions: predominantly leftward (right hemisphere bias), predominantly rightward (left hemisphere bias), or equally in both visual fields (bilateral). We measured subsequent involuntary memories immediately and for 3 days after encoding. Contrary to predictions, biased hemispheric processing did not affect short- or long-term involuntary memory frequency or duration. Future research should measure hemispheric differences at retrieval, rather than just encoding.


2018 ◽  
Vol 30 (3) ◽  
pp. 393-410 ◽  
Author(s):  
Genevieve Quek ◽  
Dan Nemrodov ◽  
Bruno Rossion ◽  
Joan Liu-Shuang

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.


2012 ◽  
Vol 24 (4) ◽  
pp. 1006-1017 ◽  
Author(s):  
Sara C. Verosky ◽  
Nicholas B. Turk-Browne

A quintessential example of hemispheric specialization in the human brain is that the right hemisphere is specialized for face perception. However, because the visual system is organized contralaterally, what happens when faces appear in the right visual field and are projected to the nonspecialized left hemisphere? We used divided field presentation and fMRI adaptation to test the hypothesis that the left hemisphere can recognize faces, but only with support from the right hemisphere. Consistent with this hypothesis, facial identity adaptation was observed in the left fusiform face area when a face had previously been processed by the right hemisphere, but not when it had only been processed by the left hemisphere. These results imply that facial identity information is transferred from the right hemisphere to the left hemisphere, and that the left hemisphere can represent facial identity but is less efficient at extracting this information by itself.


2017 ◽  
Author(s):  
Tal Seidel Malkinson ◽  
Paolo Bartolomeo

Inhibition of Return (IOR) refers to a slowing of response times (RTs) for visual stimuli repeated at the same spatial location, as compared to stimuli occurring at novel locations. The functional mechanisms and the neural bases of this phenomenon remain debated. Here we present FORTIOR, a model of the cortical control of visual IOR in the human brain. The model is based on known facts about the anatomical and functional organization of fronto-parietal attention networks, and accounts for a broad range of behavioral findings in healthy participants and brain-damaged patients. FORTIOR does that by combining four principles of asymmetry: a) Asymmetry in the networks topography, whereby the temporoparietal junction (TPJ) and ventrolateral prefrontal cortex (vlPFC) nodes are lateralized to the right hemisphere, causing higher activation levels in the right intraparietal sulcus (IPS) and frontal eye field (FEF) nodes. b) Asymmetry in inter-hemispheric connectivity, in which inter-hemispheric connections from left hemisphere IPS to right hemisphere IPS and from left hemisphere FEF to right hemisphere FEF are weaker than in the opposite direction. c) Asymmetry of visual inputs, stipulating that the FEF receives direct visual input coming from the ipsilateral visual cortex, while the right TPJ and vlPFC and IPS nodes receive input from both the contralateral and the ipsilateral visual fields. d) Asymmetry in the response modality, with a higher response threshold for the manual response system than that required to trigger a saccadic response. This asymmetry results in saccadic IOR being more robust to interference than manual IOR. FORTIOR accounts for spatial asymmetries in the occurrence of IOR after brain damage and after non-invasive transcranial magnetic stimulation on parietal and frontal regions. It also provides a framework to understand dissociations between manual and saccadic IOR, and makes testable predictions for future experiments to assess its validity.


2006 ◽  
Vol 18 (6) ◽  
pp. 1018-1028 ◽  
Author(s):  
Guillaume Thierry ◽  
Cathy J. Price

Functional neuroimaging has highlighted a left-hemisphere conceptual system shared by verbal and nonverbal processing despite neuropsychological evidence that the ability to recognize verbal and nonverbal stimuli can doubly dissociate in patients with left- and right-hemisphere lesions, respectively. Previous attempts to control for perceptual differences between verbal and nonverbal stimuli in functional neuroimaging studies may have hidden differences arising at the conceptual level. Here we used a different approach and controlled for perceptual confounds by looking for amodal verbal and nonverbal conceptual activations that are common to both the visual and auditory modalities. In addition to the left-hemisphere conceptual system activated by all meaningful stimuli, we observed the left/right double dissociation in verbal and nonverbal conceptual processing, predicted by neuropsychological studies. Left middle and superior temporal regions were selectively more involved in comprehending words—heard or read—and the right midfusiform and right posterior middle temporal cortex were selectively more involved in making sense of environmental sounds and images. Thus, the neuroanatomical basis of a verbal/nonverbal conceptual processing dissociation is established.


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