Neural reactivity tracks fear generalization gradients

Biol Psychol. 2013 Jan;92(1):2-8. doi: 10.1016/j.biopsycho.2011.12.007. Epub 2011 Dec 23.


Recent studies on fear generalization have demonstrated that fear-potentiated startle and skin conductance responses to a conditioned stimulus (CS) generalize to similar stimuli, with the strength of the fear response linked to perceptual similarity to the CS. The aim of the present study was to extend this work by examining neural correlates of fear generalization. An initial experiment (N=8) revealed that insula reactivity tracks the conditioned fear gradient. We then replicated this effect in a larger independent sample (N=25). Activation in the insula, anterior cingulate, right supplementary motor cortex and caudate increased reactivity as generalization stimuli (GS) were more similar to the CS, consistent with participants' overall ratings of perceived shock likelihood and pupillary response to each stimulus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Brain / blood supply
  • Brain / physiology*
  • Brain Mapping*
  • Conditioning, Classical / physiology
  • Conditioning, Eyelid
  • Electroshock / adverse effects
  • Fear / physiology*
  • Fear / psychology*
  • Female
  • Functional Laterality
  • Generalization, Psychological / physiology*
  • Humans
  • Image Processing, Computer-Assisted
  • Linear Models
  • Magnetic Resonance Imaging
  • Male
  • Oxygen / blood
  • Wrist / innervation
  • Young Adult


  • Oxygen