Avoided by association: acquisition, extinction, and renewal of avoidance tendencies toward conditioned fear stimuli

Traditional theoretical models hold that avoidance reflects the interplay of Pavlovian and instrumental learning. Here we suggest that avoidance tendencies to intrinsically neutral cues may be established by mere Pavlovian association. Following fear conditioning, in which pictures of one object were paired with shock (CS+) whereas pictures of another object were not (CS−), CS+ pictures facilitated avoidance reactions and interfered with approach responses, relative to CS− pictures, in a symbolic approach/avoidance reaction time task. This was achieved without any instrumental relation between responses and CS continuation or unconditioned stimulus presentation. Moreover, those avoidance tendencies were sensitive to Pavlovian extinction (they were reduced after repeated presentations of the CS+ without shock) and renewal (recovery of conditioned responding upon returning to the initial conditioning context after extinction in a different context). The present results may help us understand the self-perpetuating nature of pathological fear and anxiety.