SATO Wataru Laboratory
Temporal profile of amygdala gamma oscillations in response to faces
(Sato, Kochiyama, Uono, Matsuda, Usui, Inoue, & Toichi: J Cogn Neurosci)
Neuroimaging studies have reported greater activation of the human amygdala in response to faces than to non-facial stimuli.
However, little is known about the temporal profile of this activation.
We investigated this issue by recording the intracranial field potentials of the amygdala in subjects undergoing pre-neurosurgical assessment.
Subjects observed faces, mosaics, and houses in upright and inverted orientations using a dummy target-detection task.
Time�frequency statistical parametric mapping analyses revealed that the amygdala showed greater gamma-band activity in response to faces than to mosaics at 200�300 ms, with a peak at 255 ms.
Gamma-band activation with a similar temporal profile was also found in response to faces versus houses.
Activation patterns did not differ between upright and inverted presentations of stimuli.
These results suggest that the human amygdala is involved in the early stages of face processing, including the modulation of subjective perception of faces.