In combination, both studies demonstrate that distinct emotional states, like anxiety, are communicated chemosensorily. Especially in females, the processing of chemosensory anxiety signals requires more neuronal activity than the processing of body odor donated in an emotionally neutral condition. In socially anxious males, the processing of anxiety related chemosignals is faster than the processing of the control stimuli. Thus, the here reported results are in line with previous studies, indicating a chemosensory transmission of anxiety or stress-related experience in humans [11], [12], [14]. Most importantly, the present study could demonstrate that understanding the phenomenon of chemosensory communication of anxiety may have important applied consequences. Participants scoring high in social anxiety are at risk to develop social phobia, one of the most common anxiety disorders, with a lifetime prevalence of 12.6% [52]. As social phobia is a powerful risk factor for subsequent depressive illness and substance abuse [53], the explanation of its pathogenesis is of special importance. In the present study, socially anxious participants showed a processing advantage for chemosensory anxiety signals already at a very early level of stimulus processing. Therefore, in the future, this knowledge could gainfully be integrated into behavioral therapy of social anxiety.
