The resistance of renewal to instructions that devalue the role of contextual cues in a conditioned suppression task with humans

Prior extinction increases acquisition context specificity in human predictive learning

One experiment evaluated the effect of extinction on the context dependence of non-extinguished information in a situation in which physical (images), rather than predominantly verbal, contexts were used in human predictive learning. Participants received training in which different foods (Cues) were associated with the presence or the absence of gastric illness (outcome) in customers of different restaurants (contexts). One cue was associated with the gastric illness while a different cue was either extinguished or not between groups. A change in the context at test led to a general decrease in both predictive judgments and the speed of responding to the non-extinguished cue. However, these decreases were greater when training was conducted during extinction of the different cue demonstrating the extinction makes acquisition context-specific (EMACS) effect. Results are contrasted with failures to find the effect in other reports and discussed in terms of extinction leading to an allocation of attentional resources to the context, facilitating the context dependence of information.

Context dependency as a Function of Prediction Error-Based Attention

Context dependence of information has been shown to be based, at least in part, on the attention contexts received at the time of training. Recent research suggests that attention to irrelevant contexts may be a byproduct of the activation of a general exploratory attentional mechanism prompted by high prediction errors associated with situations of uncertainty. Alternatively, low prediction errors may engage an attentional mechanism of exploitation in situations in which contexts play a relevant role. A selective review discusses the potential of this approach to explain context switch effects from an attentional perspective.

The impact of a context switch and context instructions on the return of verbally conditioned fear

BACKGROUND AND OBJECTIVES

Repeated exposure to a conditioned stimulus can lead to a reduction of conditioned fear responses towards this stimulus (i.e., extinction). However, this reduction is often fragile and sensitive to contextual changes. In the current study, we investigated whether extinction of fear responses established through verbal threat instructions is also sensitive to contextual changes. We additionally examined whether verbal instructions can strengthen the effects of a context change.

METHODS

Fifty-two participants were informed that one colored rectangle would be predictive of an electrocutaneous stimulus, while another colored rectangle was instructed to be safe. Half of these participants were additionally informed that this contingency would only hold when the background of the computer screen had a particular color but not when it had another color. After these instructions, the participants went through an unannounced extinction phase that was followed by a context switch.

RESULTS

Results indicate that extinguished verbally conditioned fear responses can return after a context switch, although only as indexed by self-reported expectancy ratings. This effect was stronger when participants were told that CS-US contingency would depend on the background color, in which case a return of fear was also observed on physiological measures of fear.

LIMITATIONS

Extinction was not very pronounced in this study, possibly limiting the extent to which return of fear could be observed on physiological measures.

CONCLUSIONS

Contextual cues can impact the return of fear established via verbal instructions. Verbal instructions can further strengthen the contextual control of fear.

Frozen with fear: Conditioned suppression in a virtual reality model of human anxiety

Freezing-like topographies of behavior are elicited in conditioned suppression tasks whereby appetitive behavior is reduced by presentations of an aversively conditioned threat cue relative to a safety cue. Conditioned suppression of operant behavior by a Pavlovian threat cue is an established laboratory model of quantifying the response impairment seen in anxiety disorders. Little is known however about how different response topographies indicative of conditioned suppression are elicited in humans. Here, we refined a novel virtual reality (VR) paradigm in which presentations of a threat cue of unpredictable duration occurred while participants performed an operant response of shooting and destroying boxes searching for hidden gold. The VR paradigm detected significant suppression of response topographies (shots, hits and breaks) for a Pavlovian threat cue relative to a safety cue and novel cue presentations. Implications of the present findings for translational research on appetitive and aversive conflict in anxiety disorders are discussed.

Extinction treatment in multiple contexts attenuates ABC renewal in humans

Renewal has been implicated as one of the underlying mechanisms in return of fear following exposure therapy. ABC renewal is clinically more relevant than ABA renewal and yet it is a weaker form of renewal, suggesting that conducting extinction treatment in multiple contexts may be sufficient to attenuate ABC renewal. Using self-reported expectancy of shock and startle blink responses the current study examined the effects of conducting extinction treatment in multiple contexts on ABC fear renewal. Participants (N = 68) received conditional stimulus (CS) and unconditional stimulus (US) pairings in one context (A) followed by extinction treatment (CS presentations alone) in either one other context (B) or three other contexts (BCD). Non-reinforced test trials in a novel context (E) resulted in renewal of extinguished conditioned behaviour for those who received extinction in only one context. However, renewal was attenuated for those who received extinction treatment in three contexts. No renewal was found for the control group that received the test trial in the same context as during extinction. Suggestions are provided for clinicians seeking to prevent or attenuate return of fear following exposure therapy.

Giving contexts informative value makes information context-specific

Contexts are sometimes informative about relationships that occur within them and sometimes not. The goal of this experiment was to determine the effect of that information value on the context-specificity of learning. Participants performed an instrumental task within a computer game in which they defended different Andalucía beaches (contexts) by destroying several attackers (planes or tanks) by clicking on them (responses) with the mouse. A colored sensor (discriminative stimulus) indicated to participants which attacker could be destroyed in a given trial - that is, which of the instrumental responses would be reinforced. Three groups of participants received training on a discrimination between two discriminative stimuli (X and Y) in Context A. The discrimination was reversed in Context B for Group I (informative). Group NI1 received the same X-Y discrimination in Context B. Group NI2 did not receive training with X and Y in Context B. Additionally, participants received training with cue Z in Context A, which consistently signaled the same outcome. A single test trial with Z revealed a lower response rate in Context B than in Context A in Group I, while no differences across contexts were found in Groups NI1 and NI2. Results suggest that when the context is informative about relationships within the experimental setting, even those relationships for which the context is not informative become context-dependent.

The renewal of extinguished conditioned fear with fear-relevant and fear-irrelevant stimuli by a context change after extinction

The acquisition, extinction, and subsequent recovery of conditioned fear can be influenced by the nature of the conditional stimulus (CS) and the context in which the CS is presented. The combined effects of these factors were examined in a differential fear-conditioning procedure with humans. Fear-relevant or fear-irrelevant CSs were followed by a shock unconditional stimulus (US) during acquisition and presented alone during extinction. The CSs were images presented upon different background contexts. Half the participants received the same context during acquisition and extinction and the remaining received different contexts. All participants received test trials in the same context as acquisition. In Experiment 1 (N=64), a renewal of shock expectancy and skin conductance responses was found during test for fear-relevant and fear-irrelevant CSs when extinction was given in a different context. In Experiment 2 (N=72), renewal for fear-relevant stimuli was enhanced when acquisition and test was given in an indoor office context and extinction in an outdoor bush context. The opposite context configuration produced the strongest renewal for fear-irrelevant stimuli. The return of extinguished conditioned fear can occur to fear-relevant stimuli that are commonly associated with clinical fears and its strength may be enhanced when the stimuli are encountered in certain contexts after extinction.