title: Rapid amygdala gamma oscillations in response to fearful facial expressions.
abstract: Neuroimaging studies have reported greater activation of the human amygdala in response to emotional facial expressions, especially for fear. However, little is known about how fast this activation occurs. We investigated this issue by recording the intracranial field potentials of the amygdala in subjects undergoing pre-neurosurgical assessment (n=6). The subjects observed fearful, happy, and neutral facial expressions. Time-frequency statistical parametric mapping analyses revealed that the amygdala showed greater gamma-band activity in response to fearful compared with neutral facial expressions at 50-150 ms, with a peak at 135 ms. These results indicate that the human amygdala is able to rapidly process fearful facial expressions.
authors.affiliation: The Hakubi Project, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan. sato@pri.kyoto-u.ac.jp
authors.forename: Wataru
authors.initials: W
authors.lastname: Sato
authors.forename: Takanori
authors.initials: T
authors.lastname: Kochiyama
authors.forename: Shota
authors.initials: S
authors.lastname: Uono
authors.forename: Kazumi
authors.initials: K
authors.lastname: Matsuda
authors.forename: Keiko
authors.initials: K
authors.lastname: Usui
authors.forename: Yushi
authors.initials: Y
authors.lastname: Inoue
authors.forename: Motomi
authors.initials: M
authors.lastname: Toichi
mesh_terms: D000328:Adult; D000679:Amygdala / Q000502:physiology*; D001931:Brain Mapping; D004192:Discrimination, Psychological / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology*; D005149:Facial Expression; D005239:Fear / Q000502:physiology*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D011930:Reaction Time / Q000502:physiology; D012938:Social Perception