Clinical studies of epileptic or anxiety-disordered patients would be useful to address individual differences in responses to the anticonvulsant drug levetiracetam ((S)-α-Ethyl-2-oxo-1-pyrrolidineacetamide)52, which is the binding site for SV2A, and for which both beneficial67–69 or detrimental74–80 effects on emotional states and psychopathology have been reported. Here, SV2A is linked to anxiety disorder.