Vocal imitation in human infants and in some orders of birds relies on auditory-guided motor learning during a sensitive period of development. It proceeds from 'babbling' (in humans) and 'subsong' (in birds) through distinct phases towards the full-fledged communication system. Language development and birdsong learning have parallels at the behavioural, neural and genetic levels. Different orders of birds have evolved networks of brain regions for song learning and production that have a surprisingly similar gross anatomy, with analogies to human cortical regions and basal ganglia. Comparisons between different songbird species and humans point towards both general and species-specific principles of vocal learning and have identified common neural and molecular substrates, including the forkhead box P2 (FOXP2) gene.

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Songbirds (Oscines) learn their songs from a tutor. It is not known where in the brain the memories of these learned sounds are stored. Recent evidence suggests that song perception in songbirds involves neuronal activation in brain regions that have not traditionally been implicated in the control of song production or song learning, notably the caudal part of the neostriatum (NCM) and of the hyperstriatum ventrale. Zebra finch males (Taeniopygia guttata castanotis) were reared without their father and exposed to a tape-recorded song during the sensitive period for song learning. When, as adults, they were reexposed to the tutor song, the males showed increased expression of the protein products of the immediate early genes egr-1 (ZENK) and c-fos in the NCM and caudal hyperstriatum ventrale, but not in the conventional ''song-control nuclei.'' The strength of the immediate early gene response (which is a reflection of neuronal activation) in the NCM correlated significantly and positively with the number of song elements that the birds had copied from the tutor song. These results show localized neural activation in response to tutor song exposure that correlates with the strength of song learning.