title: Influence of trait anxiety on brain activity during the acquisition and extinction of aversive conditioning.
abstract: BACKGROUND
  We examined how individual differences in trait anxiety (TA) influence the neural responses associated with the acquisition and extinction of anticipatory anxiety elicited through a context conditioning paradigm, with particular focus on the amygdala and the subgenual anterior cingulate cortex (sgACC).
  
  
  METHODS
  During two sessions of echo-planar functional magnetic resonance imaging (fMRI), 18 healthy volunteers completed a decision-making task with two randomly alternating 28-s to 32-s background screen colour blocks. One of the colours was associated with the presentation of an aversive noise (CTX+) and the other colour was 'safe' (CTX-). In the first session (Acquisition), 33% of CTX+ colour blocks were paired with noise and in the second session (Extinction) no noise was presented.
  
  
  RESULTS
  The amygdala displayed an increased response to CTX+ compared to CTX- colour blocks during the Acquisition and Extinction sessions and the ACC displayed an increased response to CTX+ compared to CTX- colour blocks during Extinction only. In addition, a greater conditioned response (CTX+ minus CTX-) was observed in the ACC when comparing the Extinction and Acquisition sessions. Correlation analyses further showed that higher levels of TA were associated with a higher conditioned response in the amygdala during Extinction as well as a greater differential conditioned response (i.e. Extinction>Acquisition) in the ACC.
  
  
  CONCLUSIONS
  Our results support the idea that individuals with high levels of anxiety-relevant traits and vulnerable to developing an anxiety disorder display a more resilient anxiety response during extinction that is characterized by hyper-responsivity in the amygdala.
authors.affiliation: Douglas Mental Health University Institute, McGill University, Montreal, Quebec, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Barrett
authors.forename: J L
authors.initials: JL
authors.lastname: Armony
mesh_terms: D000679:Amygdala / Q000503:physiopathology*; D001008:Anxiety Disorders / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology*; D003213:Conditioning, Psychological; D004924:Escape Reaction; D005108:Extinction, Psychological; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006179:Gyrus Cinguli / Q000503:physiopathology*; D006801:Humans; D007858:Learning; D008279:Magnetic Resonance Imaging; D008297:Male; D011795:Surveys and Questionnaires; D055815:Young Adult