Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2010 Jun;14(6):268-76.
doi: 10.1016/j.tics.2010.04.002. Epub 2010 May 20.

Overlapping neural systems mediating extinction, reversal and regulation of fear

Daniela Schiller  1 , Mauricio R Delgado
Affiliations
Review

Overlapping neural systems mediating extinction, reversal and regulation of fear

Daniela Schiller et al. Trends Cogn Sci. 2010 Jun.

Abstract

Learned fear is a process allowing quick detection of associations between cues in the environment and prediction of imminent threat. Adaptive function in a changing environment, however, requires organisms to quickly update this learning and have the ability to hinder fear responses when predictions are no longer correct. Here we focus on three strategies that can modify conditioned fear, namely extinction, reversal and regulation of fear, and review their underlying neural mechanisms. By directly comparing neuroimaging data from three separate studies that employ each strategy, we highlight overlapping brain structures that comprise a general circuitry in the human brain. This circuitry potentially enables the flexible control of fear, regardless of the particular task demands.

PubMed Disclaimer

Figures

Figure 1
Figure 1. Schematic of the experimental procedures
The three tasks were based on a discrimination fear conditioning paradigm with partial reinforcement. The aversive outcome was a mild electric shock to the wrist (US, unconditioned stimulus). The conditioned stimuli were colored squares (in extinction and regulation) or faces (in reversal). For discrimination, one specific stimulus (e.g., a yellow square) was designated as the conditioned stimulus (CS+) and was paired with the shock on about 30% of the trials, whereas the other stimulus (e.g., a blue square) was never paired with the shock (CS−). In extinction, the conditioning session was followed by two extinction sessions (one immediately after and the other 24 hours later) consisted of repeated non-reinforced presentations of the CS+ and CS−. In reversal, the conditioning session was immediately followed by an identical conditioning session only with reversed reinforcement contingencies, such that the stimuli designated as CS+ and CS− flipped roles. In regulation, the conditioning trials were interleaved with the regulation trials. Before each trial, subjects were instructed to either attend (“Try to focus on your natural feelings”) or to regulate (“Try to think of something calming in nature”). The index of fear was skin conductance responses (SCR) detected by two electrodes attached to the first and second fingers. In all tasks, the stimuli were presented for 4 sec and the inter-trial-interval was 12 sec. The US lasted 200 msec co-terminating with the conditioned stimulus. Each trial type was typically presented 12-16 times.
Figure. 2
Figure. 2
Brain regions showing correlation between BOLD signals and SCR during reversal of conditioned fear (Placed in Box 1)
Figure. 3
Figure. 3
Overlapping regions in the striatum and vmPFC show consistent activation patterns across three different fear modulation strategies (Placed in Box 2)
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Pearce JM, Hall G. A model for Pavlovian learning: variations in the effectiveness of conditioned but not of unconditioned stimuli. Psychol Rev. 1980;87:532–552. - PubMed
    1. Bouton ME, et al. Contextual and temporal modulation of extinction: behavioral and biological mechanisms. Biol Psychiatry. 2006;60:352–360. - PubMed
    1. Kehagia AA, et al. Learning and cognitive flexibility: frontostriatal function and monoaminergic modulation. Curr Opin Neurobiol. 2010 DOI 10.1016/j.conb.2010.1001.1007. - PubMed
    1. LeDoux JE. Emotion circuits in the brain. Annu Rev Neurosci. 2000;23:155–184. - PubMed
    1. Ochsner KN, Gross JJ. The cognitive control of emotion. Trends Cogn Sci. 2005;9:242–249. - PubMed

Publication types