occurs are particularly aversive (Haller et al., 2009; Naidu et al., 2007). This finding suggests that inhibition of FAAH under stable conditions does little to modulate emotional behaviour, but following exposure to aversive environmental conditions, FAAH activity may increase which results in a decline in AEA signaling which is conducive to the development of anxiety-like behaviours. As such, inhibition of FAAH may counter the decline in AEA that occurs following exposure to stressful stimuli, and in turn, prevent the facilitation of anxiety-like behaviour that accompanies stressful experiences. This hypothesis can account for both the environmentally specific effects of FAAH inhibitors and the modest effects that FAAH inhibition produces on anxiety behaviour relative to a standard anxiolytic, such as diazepam (Haller et al., 2009; Naidu et al., 2007).
