Dynamic control of auditory activity during sleep: Correlation between song response and EEG

The song nucleus high vocal center (HVC) sends neural signals for song prod uction and receives auditory input. By using electroencephalography (EEG) t o objectively identify wake/sleep state, we show that HVC auditory response s change with physiological states. Comparison of EEG and HVC records revea led that HVC response to auditory stimuli is greatest during slow-wave slee p. During slow-wave sleep, HVC neurons responded preferentially to the bird 's own song. Strikingly, both spontaneous and forced waking during sleep ca used HVC auditory responses to cease within milliseconds of an EEG-measured state change. State-dependent phenomena in downstream nuclei, such as robu stus archistriatalis, are likely to be derivatives of those in HVC.