Inferred threat and safety: symbolic generalization of human avoidance learning.

Symbolic generalization of avoidance may underlie the aetiology and maintenance of anxiety disorders. The aim of the present study was to demonstrate inferred threat-avoidance and safety (non-avoidance) behaviours that occur in the presence of stimuli indirectly related to learned threat and safety cues. A laboratory experiment was conducted involving two symbolic stimulus equivalence relations consisting of three physically dissimilar stimuli (avoidance cues: AV1-AV2-AV3 and neutral cues: N1-N2-N3). During avoidance learning involving aversive images and sounds, a key-press avoidance response was trained for one member of one of the relations (AV2) and non-avoidance for another (N2). Inferred threat and safety behaviour and ratings of the likelihood of aversive events were tested with presentations of all remaining stimuli. Findings showed a significantly high percentage of avoidance to both the learned and inferred threat cues and less avoidance to both the learned and inferred safety cues. Ratings in the absence of avoidance were high during training and testing to threat cues and low to safety cues and were generally lower in the presence of avoidance. Implications for associative and behavioural accounts of avoidance, and modern therapies for anxiety disorders are discussed.