Timing of Extinction Relative to Acquisition: A Parametric Analysis of Fear Extinction in Humans

Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA.
Behavioral Neuroscience (Impact Factor: 2.73). 11/2008; 122(5):1016-30. DOI: 10.1037/a0012604
Source: PubMed


Fear extinction is a reduction in conditioned fear following repeated exposure to the feared cue in the absence of any aversive event. Extinguished fear often reappears after extinction through spontaneous recovery. Animal studies suggest that spontaneous recovery can be abolished if extinction occurs within minutes of acquisition. However, a limited number of human extinction studies have shown that short interval extinction does not prevent the return of fear. For this reason, we performed an in-depth parametric analysis of human fear extinction using fear-potentiated startle. Using separate single-cue and differential conditioning paradigms, participants were fear conditioned and then underwent extinction either 10 min (Immediate) or 72 hr (Delayed) later. Testing for spontaneous recovery occurred 96 hr after acquisition. In the single cue paradigm, the Immediate and Delayed groups exhibited differences in context, but not fear, conditioning. With differential conditioning, there were no differences in context conditioning and the Immediate group displayed less spontaneous recovery. Thus, the results remain inconclusive regarding spontaneous recovery and the timing of extinction and are discussed in terms of performing translational studies of fear in humans.

Download full-text


Available from: Bram Vervliet,
  • Source
    • "Interestingly, the observation of nondifferential (generalized ) ROF is also evident in other ROF phenomena such as renewal (for review, see Vervliet et al. 2013a) and spontaneous recovery (Norrholm et al. 2008). Further complicating matters, often a mixture of differential, generalized, and no reinstatement effects in different dependent measures is reported within one study (see Table 1 for a detailed summary of the results of human studies). "

  • Source
    • "Although some studies have shown that spontaneous recovery can be modified by the delay intervals between acquisition and extinction testing (e.g. Huff, Hernandez, Blanding, & LaBar, 2009; Norrholm et al., 2008; Schiller et al., 2008), it is unknown whether multiple-context extinction has any effect on spontaneous fear recovery. Spontaneous recovery is typically tested in the extinction context following a delay (i.e. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Although conditioned fear can be effectively extinguished by unreinforced exposure to a threat cue, fear responses tend to return when the cue is encountered some time after extinction (spontaneous recovery), in a novel environment (renewal), or following presentation of an aversive stimulus (reinstatement). As extinction represents a context-dependent form of new learning, one possible strategy to circumvent the return of fear is to conduct extinction across several environments. Here, we tested the effectiveness of multiple context extinction in a two-day fear conditioning experiment using 3-D virtual reality technology to create immersive, ecologically-valid context changes. Fear-potentiated startle served as the dependent measure. All three experimental groups initially acquired fear in a single context. A multiple extinction group then underwent extinction in three contexts, while a second group underwent extinction in the acquisition context and a third group underwent extinction in a single different context. All groups returned 24 hours later to test for return of fear in the extinction context (spontaneous recovery) and a novel context (renewal and reinstatement/test). Extinction in multiple contexts attenuated reinstatement of fear but did not reduce spontaneous recovery. Results from fear renewal were tendential. Our findings suggest that multi-context extinction can reduce fear relapse following an aversive event – an event that often induces return of fear in real-world settings -- and provides empirical support for conducting exposure-based clinical treatments across a variety of environments.
    Neurobiology of Learning and Memory 09/2014; 113. DOI:10.1016/j.nlm.2014.02.010 · 3.65 Impact Factor
  • Source
    • "Interestingly, the observation of non-differential (generalized) ROF is also evident in other ROF phenomena such as renewal (reviewed by Vervliet et al., 2013a) and spontaneous recovery (Norrholm et al., 2008). Further complicating matters, often a mixture of differential, generalized and no reinstatement effects in different dependent measures is reported within one study (see Table1 for a detailed summary of the results of human studies). "
    [Show abstract] [Hide abstract]
    ABSTRACT: In human research, studies of return of fear (ROF) phenomena, and reinstatement in particular, began only a decade ago and recently are more widely used, e.g., as outcome measures for fear/extinction memory manipulations (e.g., reconsolidation). As reinstatement research in humans is still in its infancy, providing an overview of its stability and boundary conditions and summarizing methodological challenges is timely to foster fruitful future research. As a translational endeavor, clarifying the circumstances under which (experimental) reinstatement occurs may offer a first step toward understanding relapse as a clinical phenomenon and pave the way for the development of new pharmacological or behavioral ways to prevent ROF. The current state of research does not yet allow pinpointing these circumstances in detail and we hope this review will aid the research field to advance in this direction. As an introduction, we begin with a synopsis of rodent work on reinstatement and theories that have been proposed to explain the findings. The review however mainly focuses on reinstatement in humans. We first describe details and variations of the experimental setup in reinstatement studies in humans and give a general overview of results. We continue with a compilation of possible experimental boundary conditions and end with the role of individual differences and behavioral and/or pharmacological manipulations. Furthermore, we compile important methodological and design details on the published studies in humans and end with open research questions and some important methodological and design recommendations as a guide for future research.
    Learning &amp Memory 08/2014; 21(9). DOI:10.1101/lm.036053.114 · 3.66 Impact Factor
Show more