Introducing songbirds as a model system for epilepsy research.

It has been broadly recognized that the avian forebrain shares extensive homology with neocortex, and the two share similar patterns of input, local circuit, and output connectivity. Some songbird species also exhibit a full range of vigilance states and ultradian patterns in gross (EEG) potentials that are commonly seen in mammals. The avian forebrain is organized in a field and nuclear fashion, giving great technical advantage especially when manipulating specialized regions such as forebrain song system nuclei associated with vocal learning that would be hard to achieve in cortex. Songbirds are a model system for studying developmental processes at multiple levels of analysis, including but not limited to mechanistic electrophysiological descriptions of vocal production and vocal learning process. Recent behavioral evidence establishes a role for sleep in the vocal learning process of birds. This is likely to be related to the observed neuronal replay during sleep in songbirds and its emergence at the onset of exposure to a song tutor and formation of an auditory memory. These features of birdsong learning and the song system position it as an attractive model system for systems-level epilepsy research, especially for pediatric epilepsies and for those that are expressed during sleep and affect language development.