Authors:

CALDER, A.J., BEAVER, J.D., Winston, J.S., Dolan, R.J., JENKINS, R., Eger, E. & HENSON, R.N.A.

Reference:

Year of publication:

2007

CBU number:

6354

Abstract:

Electrophysiological recording in the anterior superior temporal sulcus (STS) of monkeys has demonstrated separate cell populations responsive to direct and averted gaze [1, 2]. Human functional imaging has demonstrated posterior STS activation in gaze processing, particularly in coding the intentions conveyed by gaze [3-6], but to date has provided no evidence of dissociable coding of different gaze directions. Since the spatial resolution typical of group-based fMRI studies (~6-10mm) exceeds the size of cellular patches sensitive to different facial characteristics (1-4mm in monkeys) a more sensitive technique may be required. fMRI-adaptation, which is considered to offer superior resolution [7], was therefore used to investigate whether the human anterior STS contains representations of different gaze directions, as suggested by non-human primate research. Subjects viewed probe faces gazing left, directly ahead, or right. Adapting to leftward gaze produced a reduction in BOLD response to left relative to right (and direct) gaze probes in the anterior STS and inferior parietal cortex; rightward gaze adaptation produced a corresponding reduction to right gaze probes. Consistent with these findings, averted gaze in the adapted direction was misidentified as direct. Our study provides the first human evidence of dissociable neural systems for left and right gaze. Was listed under: Separate Coding of Different Gaze Directions in the Anterior Temporal Sulcus and Inferior Parietal Lobule