Evidence for expectancy as a mediator of avoidance and anxiety in a laboratory model of human avoidance learning

Abstract

A laboratory model was developed to study human avoidance learning. Participants could avoid an electric shock signalled by a 5-s conditioned stimulus (CS) by pressing one of a set of response buttons. Self-reported shock expectancy and skin conductance were recorded during a subsequent 10-s interval before shock. Shock expectancy declined when the correct avoidance response was learned and returned when the response was unavailable. Learning transferred to another shock CS. Parallel effects were observed on skin conductance once performance anxiety was controlled by requiring responding on all trials. Learning was faster when the Pavlovian contingencies were trained before introduction of the instrumental response. The results support a cognitive model of anxiety in which performance of an avoidance response reduces expectancy of an aversive outcome and thereby reduces anxiety.

Social anxiety and cognitive expectancy of aversive outcome in avoidance conditioning

“…This model is described as a cognitive model of anxiety in which performance of an avoidance response reduces expectancy of an aversive outcome and thereby reduces anxiety. This cognitive expectancy model is supported by evidence from a lab based paradigm of human avoidance learning (Lovibond, Saunders, Weideman, & Mitchell, 2008). Although the paradigm was successfully used to study the cognitive accounts of avoidance, it has not been applied to study the relation with social anxiety yet.…”

“…Following Lovibond et al (2008), acquisition of the avoidance response was defined by a criterion of at least two consecutive correct responses on the A(þ) trials during the acquisition phase. The skin conductance measure was the change in mean skin conductance level from the 5 s pre CS baseline period to the final 5 s of the post CS delay period (dSCL).…”

“…The skin conductance measure was the change in mean skin conductance level from the 5 s pre CS baseline period to the final 5 s of the post CS delay period (dSCL). The final 5 s of the post CS delay period was found to be most sensitive for distinguishing between various trial types (Lovibond et al, 2008). dSCL data was log transformed as follows, log (post CS score þ 1) log (baseline score þ 1) to minimize individual differences and normalize the distribution.…”

“…Allover, we expected that acquisition of the avoidance response would reduce US expectancy that would lead to reduced anxiety (Lovibond et al, 2008). For HSA we formulated three specific hypotheses: First, based on the previously found expectancy bias in social phobics Veit et al, 2002), we pre dicted HSA to show an enhanced US expectancy compared to LSA in the first stage of avoidance learning, when the functionality of the avoidance response still needs to be proven.…”

“…We used a modified version of the human avoidance learning paradigm (Lovibond et al, 2008) to test the cognitive expectancy account of avoidance in social anxiety. Following Lovibond and colleagues, we measured change from baseline skin conductance level (dSCL) as an autonomic measure of anxiety and on line subjective expectancy of US (Lovibond, 1992).…”