Document Type

Article

Source of Publication

PLoS ONE

Publication Date

7-17-2014

Abstract

When observing a talking face, it has often been argued that visual speech to the left and right of fixation may produce differences in performance due to divided projections to the two cerebral hemispheres. However, while it seems likely that such a division in hemispheric projections exists for areas away from fixation, the nature and existence of a functional division in visual speech perception at the foveal midline remains to be determined. We investigated this issue by presenting visual speech in matched hemiface displays to the left and right of a central fixation point, either exactly abutting the foveal midline or else located away from the midline in extrafoveal vision. The location of displays relative to the foveal midline was controlled precisely using an automated, gaze-contingent eye-tracking procedure. Visual speech perception showed a clear right hemifield advantage when presented in extrafoveal locations but no hemifield advantage (left or right) when presented abutting the foveal midline. Thus, while visual speech observed in extrafoveal vision appears to benefit from unilateral projections to left-hemisphere processes, no evidence was obtained to indicate that a functional division exists when visual speech is observed around the point of fixation. Implications of these findings for understanding visual speech perception and the nature of functional divisions in hemispheric projection are discussed. © 2014 Jordan et al.

ISSN

1932-6203

Publisher

Public Library of Science

Volume

9

Issue

7

First Page

e98273

Disciplines

Life Sciences

Keywords

adult; article; clinical article; controlled study; eye fixation; eye tracking; female; gaze; hemisphere; hemispheric dominance; human; left hemisphere; male; nerve projection; retina fovea; retina receptive field; speech; speech perception; vision; adolescent; eye movement; face; facial expression; hemispheric dominance; pattern recognition; physiology; retina fovea; speech perception; United Kingdom; vision; young adult; Adolescent; Adult; Eye Movements; Face; Facial Expression; Fixation, Ocular; Fovea Centralis; Functional Laterality; Great Britain; Humans; Pattern Recognition, Visual; Speech; Speech Perception; Vision, Ocular; Visual Perception; Young Adult

Scopus ID

84904489223

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

Indexed in Scopus

yes

Open Access

yes

Open Access Type

Gold: This publication is openly available in an open access journal/series

Included in

Life Sciences Commons

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