Time-varying amygdala response to emotional faces in generalized social phobia.
BACKGROUND
Individuals with social phobia (SP) have altered behavioral and neural responses to emotional faces and are hypothesized to have deficits in inhibiting emotion-related amygdala responses. We tested for such amygdala deficits to emotional faces in a sample of individuals with SP.


METHODS
We used functional magnetic resonance imaging (fMRI) to examine the neural substrates of emotional face processing in 14 generalized SP (gSP) and 14 healthy comparison (HC) participants. Analyses focused on the temporal dynamics of the amygdala, prefrontal cortex (PFC), and fusiform face area (FFA) across blocks of neutral, fear, contempt, anger, and happy faces in gSP versus HC participants.


RESULTS
Amygdala responses in participants with gSP occurred later than the HC participants to fear, angry, and happy faces. Parallel PFC responses were found for happy and fear faces. There were no group differences in temporal response patterns in the FFA.


CONCLUSIONS
This finding might reflect a neural correlate of atypical orienting responses among individuals with gSP. Commonly reported SP deficits in habituation might reflect neural regions associated with emotional self-evaluations rather than the amygdala. This study highlights the importance of considering time-varying modulation when examining emotion-related processing in individuals with gSP.
Campbell
Darren W
DW
Department of Psychiatry, University of Manitoba, Winnipeg, Manitoba, Canada. dcampb@cc.umanitoba.ca
Sareen
Jitender
J
Paulus
Martin P
MP
Goldin
Philippe R
PR
Stein
Murray B
MB
Reiss
Jeffrey P
JP
D000328:Adult; D000679:Amygdala / Q000098:blood supply / Q000503:physiopathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D019260:Expressed Emotion / Q000502:physiology*; D005145:Face / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010100:Oxygen / Q000097:blood; D010698:Phobic Disorders / Q000473:pathology* / Q000503:physiopathology*; D010775:Photic Stimulation / Q000379:methods; D012720:Severity of Illness Index; D013997:Time Factors
D010100:Oxygen