Impaired discriminative fear conditioning during later training trials differentiates generalized anxiety disorder, but not panic disorder, from healthy control participants

Background: Fear conditioning is implicated as a central psychopathological mechanism of anxiety disorders. People with anxiety disorders typically demonstrate reduced affective discrimination between conditioned danger and safety cues. Here, affective discrimination refers to the ability to selectively display fear to dangerous but not safe situations. Though both generalized anxiety disorder (GAD) and panic disorder (PD) are linked to impaired affective discrimination, the clinical phenomenology of these disorders suggests that people with GAD versus PD might be less able to overcome such deficits. It is unclear how this potential difference would manifest during lab-based conditioning. Methods: We used a classical fear conditioning paradigm over two discrimination training sessions to examine whether those with GAD, but not PD, would display persistent discrimination deficits. Sixty-seven participants (21 GAD, 19 PD, 27 Healthy Controls) completed a task in which conditioned fear was measured psychophysiologically (fear-potentiated startle), behaviorally, and via self-report. Results: Although similar levels of impaired discrimination were found for both GAD and PD groups during initial training, such impairments tended to persist across a subsequent training session only for patients with GAD when compared with Controls. Conclusion: Our results provide a foundation for additional research of discrimination deficits in specific anxiety disorders, with an ultimate goal of improved customization of psychological treatments. (C) 2018 Elsevier Inc. All rights reserved.