Unconditioned responses and functional fear networks in human classical conditioning.

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Version: author
Serval ID
serval:BIB_1E73A45BD8D7
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Unconditioned responses and functional fear networks in human classical conditioning.
Journal
Behavioural Brain Research
Author(s)
Linnman C., Rougemont-Bücking A., Beucke J.C., Zeffiro T.A., Milad M.R.
ISSN
1872-7549 (Electronic)
ISSN-L
0166-4328
Publication state
Published
Issued date
2011
Peer-reviewed
Oui
Volume
221
Number
1
Pages
237-245
Language
english
Abstract
Human imaging studies examining fear conditioning have mainly focused on the neural responses to conditioned cues. In contrast, the neural basis of the unconditioned response and the mechanisms by which fear modulates inter-regional functional coupling have received limited attention. We examined the neural responses to an unconditioned stimulus using a partial-reinforcement fear conditioning paradigm and functional MRI. The analysis focused on: (1) the effects of an unconditioned stimulus (an electric shock) that was either expected and actually delivered, or expected but not delivered, and (2) on how related brain activity changed across conditioning trials, and (3) how shock expectation influenced inter-regional coupling within the fear network. We found that: (1) the delivery of the shock engaged the red nucleus, amygdale, dorsal striatum, insula, somatosensory and cingulate cortices, (2) when the shock was expected but not delivered, only the red nucleus, the anterior insular and dorsal anterior cingulate cortices showed activity increases that were sustained across trials, and (3) psycho-physiological interaction analysis demonstrated that fear led to increased red nucleus coupling to insula but decreased hippocampus coupling to the red nucleus, thalamus and cerebellum. The hippocampus and the anterior insula may serve as hubs facilitating the switch between engagement of a defensive immediate fear network and a resting network.
Pubmed
Web of science
Create date
08/06/2011 8:49
Last modification date
15/06/2020 6:08
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