Positive affect predicts less reacquisition of fear: relevance for long-term outcomes of exposure therapy.

Much emphasis in fear conditioning research is placed on understanding extinction learning, partly because of its application in treating anxiety disorders. Return of fear after extinction is a problem affecting long-term maintenance of treatment gains. The present study evaluated whether positive affect (PA) is associated with lower rates of reacquisition, or, an increase in fear following re-pairings of the conditional stimulus (CS+) and unconditional stimulus (US; e.g. electric shock) after extinction. Results showed that higher PA before and after extinction was associated with less CS+ fear during reacquisition as measured by skin conductance arousal and US expectancy. Conversely, negative affect was not associated with reacquisition of fear using any measure. These results provide implications for reducing reacquisition with exposure therapy for anxiety disorders.