Avoidance and escape: Defensive reactivity and trait anxiety.

Although avoidance and escape behaviors each contribute to maintaining anxiety disorders, only avoidance completely eliminates exposure to the aversive context. Current research compared anticipatory defensive engagement when aversion could either be completely avoided or escaped after initial exposure; in addition, this research examined the impact of trait anxiety on coping-related defensive engagement. Cues signaled that upcoming rapid action would avoid (block), escape (terminate), or not affect subsequent aversive exposure; the acoustic startle reflex was measured during each anticipatory interval to index defensive engagement, and blink magnitudes were compared across low-, moderate-, and high-anxious individuals. For all participants, startle was potentiated when aversive exposure was uncontrollable and attenuated when aversion was avoidable. On escape trials, on the other hand, startle potentiation increased with rising participant anxiety. Results suggest 1) defensive engagement is generally reduced in avoidance contexts relative to contexts in which exposure is certain, and; 2) trait anxiety increases defensive engagement specifically when aversive exposure can be controlled but remains certain.