Aniracetam (1-(4-methoxybenzoyl)-2-pyrrolidinone, also 1-p-anisoyl-2-pyrrolidinone) is a pyrrolidinone-type compound of the racetam family. Its best-characterised action is positive allosteric modulation of AMPA-type glutamate receptors, described in Xenopus oocytes and rat hippocampal slices in 1990 and later examined at the structural level. Rodent studies have examined its metabolites, cholinergic transmission and behaviour in models of anxiety and cognition. Several of its effects in vivo have been attributed to its major metabolites, N-anisoyl-GABA and p-anisic acid.