Avoidance behavior maintains threat beliefs

Anxiety disorders are maintained by excessive threat beliefs. It remains unclear why these beliefs persist despite the availability of disconfirming information. It has been proposed that threat beliefs are maintained by avoidance behavior; that is, behavior aimed at preventing the feared catastrophe. This way, the non-occurrence of the catastrophe may be misattributed to this behavior. Using a classical conditioning paradigm, Lovibond and colleagues (2009) showed that avoidance behavior maintains treat beliefs. We aimed to replicate this finding, and, additionally, investigated the effect of avoidance behavior on anticipatory pupillary dilation as a measure of fear conditioning. Fifty-six undergraduate student participants learned that two neutral stimuli (e.g., a square and triangle; stimulus A and C), were followed by an aversive loud noise, and a third (e.g., circle; stimulus B), was not. Next, they learned that when a symbol lit up during stimulus presentation, they could unplug the headphone, which prevented them from hearing the loud noise (avoidance behavior). In an extinction phase, stimulus C was no longer followed by the loud noise. However, for participants in the experimental group (n = 28), the symbol lit up during presentation of C, and participants performed avoidance behavior. In a final test phase, C was presented once without the availability of the avoidance response. Participants rated their expectancy of the loud noise online, and anticipatory pupillary dilation was measured during stimulus presentation. In line with expectations, the experimental group had higher threat expectations for stimulus C in the test phase than participants in the control group. Pupillary responses showed similar effects. It appears that the avoidance response had prevented participants in the experimental group from obtaining the information that stimulus C was no longer followed by the loud noise. This suggests that avoidance behavior maintains threat beliefs. Implications for clinical practice will be discussed.