Recent studies have shown that avoidance behavior may become excessive and inflexible
(i.e., detached from its incentive value and resistant to extinction). On the other hand,
prospective intolerance of uncertainty (P-IU) has been defined as a factor leading to
excessive responding in uncertain situations. Thus, uncertain avoidance situations may be
taken as a relevant scenario to examine the role of intolerance of uncertainty as a factor that
facilitates excessive and inflexible avoidance behavior. In our experiment, we tested the
hypothesis that P-IU is associated with excessive and inflexible avoidance in an outcome
devaluation paradigm. Specifically, healthy participants learned in a free-operant
discriminative task to avoid an aversive sound, and were tested in extinction to measure the
sensitivity of avoidance responses to the devaluation of the sound aversiveness. The results
showed that an increase in P-IU was positively associated to an increase in insensitivity to the
devaluation. Moreover, P-IU was also related to an increase in the frequency of avoidance
responses during the instrumental learning phase, and to resistance to extinction.
Interestingly, these associations involving P-IU were still significant when trait anxiety was
controlled for. The pattern of results suggests that P-IU may be a vulnerability factor for
excessive and inflexible avoidance, which, in turn, has been found to be associated with
several mental disorders.
