Induction of conditioned avoidance via mental imagery.

There is a growing interest on how mental imagery may be involved in the onset and maintenance of anxiety-related disorders. Here, we used an experimental design to investigate whether a key symptom across anxiety-related disorders, namely avoidance, can be induced via mental imagery. Healthy participants first learned that one neutral stimulus (A) was associated with a mild electric shock and two other neutral stimuli (B and C) were not. They then learned to cancel the shock when A was presented, by pressing a button on a keyboard ('behavioral avoidance'). Next, they were asked to imagine that stimulus B was followed by the shock (i.e., without actual B or shock presentations; Experiment 1; N = 66) or they were shown B and asked to imagine the shock (i.e., without actual shock presentations; Experiment 2; N = 60). Finally, in the test phase, they were shown each of the three stimuli (without the shock) and given the opportunity to make the avoidance response. Results showed that participants tended to avoid B in the test phase in Experiment 1, even though it had never been presented with the shock but not in Experiment 2. We discuss how the findings may explain the acquisition of avoidance in the presentation of innocuousstimuli across anxiety-related disorders.