Context-dependent human extinction memory is mediated by a ventromedial prefrontal and hippocampal network.
In fear extinction, an animal learns that a conditioned stimulus (CS) no longer predicts a noxious stimulus [unconditioned stimulus (UCS)] to which it had previously been associated, leading to inhibition of the conditioned response (CR). Extinction creates a new CS-noUCS memory trace, competing with the initial fear (CS-UCS) memory. Recall of extinction memory and, hence, CR inhibition at later CS encounters is facilitated by contextual stimuli present during extinction training. In line with theoretical predictions derived from animal studies, we show that, after extinction, a CS-evoked engagement of human ventromedial prefrontal cortex (VMPFC) and hippocampus is context dependent, being expressed in an extinction, but not a conditioning, context. Likewise, a positive correlation between VMPFC and hippocampal activity is extinction context dependent. Thus, a VMPFC-hippocampal network provides for context-dependent recall of human extinction memory, consistent with a view that hippocampus confers context dependence on VMPFC.
Kalisch
Raffael
R
Wellcome Department of Imaging Neuroscience, Functional Imaging Laboratory, Institute of Neurology, University College London, London, WC1N 3BG, United Kingdom. rkalisch@uke.uni-hamburg.de
Korenfeld
Elian
E
Stephan
Klaas E
KE
Weiskopf
Nikolaus
N
Seymour
Ben
B
Dolan
Raymond J
RJ
D000293:Adolescent; D000328:Adult; D001362:Avoidance Learning / Q000502:physiology; D001931:Brain Mapping; D003213:Conditioning, Psychological / Q000502:physiology; D004558:Electric Stimulation / Q000009:adverse effects; D005108:Extinction, Psychological / Q000502:physiology*; D005145:Face; D005239:Fear / Q000502:physiology; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D009415:Nerve Net / Q000033:anatomy & histology / Q000502:physiology*; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology*; D017397:Prefrontal Cortex / Q000033:anatomy & histology / Q000502:physiology*