Preparatory neural activations in basal ganglia related with learned songs and innate calls in Java sparrows In addition to female-directed courtship songs, male songbirds also sing undirected songs (US). During US, the anterior forebrain pathway (AFP) of songbird brain plays an important role. In Area X, a nucleus of AFP in basal ganglia, activity of all pallidal and some striatal neurons increases during US (Goldberg et al., 2011; Fee and Goldberg, 2011). Although these studies show that Area X neurons are involved in song production, it is still unclear whether neural activity during US is different from that during other vocal behav- iors suchas innate calls. Java sparrows (Lonchura oryzivora) vocalize trill calls, which have longer duration than other calls and are used for social communication in addition to learned song. Thus, they might be a good model for investigating long-term effect of vocal- izations on neural activity. In the present study, we explored how the neural activity of Area X correlated with vocal behaviors and their pre- and post-periods. We implanted electrode in Area X of 4 male adult Java sparrows, and recorded neural activity under free- moving condition. We analyzed firing rate change around US bouts, including calls and introductory notes prior to song syllables and compared it with that of innate calls. We found that firing rate of singing-related Area X neuron gradually increased for few seconds before onsets of US bouts, prior to any vocalization such as intro- ductory notes or calls before song syllables in most neurons. The gradual change of neural activity also occurred prior to trill calls, which was more transiently than around song bouts. The results suggest that activity change in Area X neuron is differently mod- ulated by the category of vocalizations, and its gradual increase in firing rate might reflect long-term changes in motivational states of vocalization.
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