Response to Hubbeling Letter

To the Editor: Dr. Hubbeling provides a thoughtful commentary on our recent article on social norm processing in generalized social phobia, making two points that we will consider in turn.

First, while acknowledging that we excluded alternative explanations of our findings, such as the potential impact of depressive symptoms, Dr. Hubbeling rightly points out that the stimulus example used in our article involved a disgusting social norm violation and wonders whether all of the transgression behaviors used in the study involved themes of disgust. Dr. Hubbeling then considers whether such disgust content could explain the increased insula response observed in the patients with generalized social phobia (group main effect) across the three transgression types. This is an interesting point that we had failed to consider in our paper. Of the 26 embarrassing transgressions, four involved themes of disgust, while the remaining 22 involved non-disgust themes (e.g., forgetting to tip a waiter for good service or accidentally hanging up on a friend during a phone call). Thus, it seems unlikely that disgust content directly contributed to the observed group difference in the insula in our study, although we do not rule out a potential role of disgust in other generalized social phobia-related studies. In this regard, it is also worth noting that we did not observe any group-by-transgression interaction within the insula, a result we might have expected if disgust had differentially affected the two groups, given that the behaviors categorized as no transgression, as indeed the naming implies, never involved any disgust behaviors.

A second point made by Dr. Hubbeling is that the stimuli used in fMRI studies should be made publicly available. We completely agree with this point and confirm that the stimuli used in the study are available by request from the corresponding author (K.S.B.).