Amygdala engagement in response to subthreshold presentations of anxious face stimuli in adults with autism spectrum disorders: preliminary insights.
Current theoretical models of autism spectrum disorders (ASD) have proposed that impairments in the processing of social/emotional information may be linked to amygdala dysfunction. However, the extent to which amygdala functions are compromised in ASD has become a topic of debate in recent years. In a jittered functional magnetic resonance imaging study, sub-threshold presentations of anxious faces permitted an examination of amygdala recruitment in 12 high functioning adult males with ASD and 12 matched controls. We found heightened neural activation of the amygdala in both high functioning adults with ASD and matched controls. Neither the intensity nor the time-course of amygdala activation differed between the groups. However, the adults with ASD showed significantly lower levels of fusiform activation during the trials compared to controls. Our findings suggest that in ASD, the transmission of socially salient information along sub-cortical pathways is intact: and yet the signaling of this information to structures downstream may be impoverished, and the pathways that facilitate subsequent processing deficient.
Department of Psychiatry and Behavioural Neurosciences, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada. hallg@mcmaster.ca
Geoffrey B C
GB
Hall
Krissy A R
KA
Doyle
Jeremy
J
Goldberg
Dianne
D
West
Peter
P
Szatmari
D000328:Adult; D000679:Amygdala / Q000502:physiology*; D001007:Anxiety / Q000503:physiopathology*; D001519:Behavior; D001931:Brain Mapping; D002659:Child Development Disorders, Pervasive / Q000503:physiopathology* / Q000523:psychology*; D002675:Child, Preschool; D003710:Demography; D005145:Face; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010470:Perceptual Masking; D010775:Photic Stimulation; D010865:Pilot Projects; D012684:Sensory Thresholds / Q000502:physiology*; D012727:Sex Characteristics; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult