Fig. 4

Sleep–wake cycles are altered in Ube3a-del mice. a A schematic detailing how each sleep state is binned using representative samples. A (i) wake state was characterized by a low-amplitude, high-frequency signal with low-EMG tone, while an (ii) active wake state was distinguished by high-EMG tone and activity. Sleep was divided into either a slow-wave sleep state or a paradoxical sleep state. (iii) Slow-wave sleep was defined by having a high-amplitude, low-frequency signal with elevated delta power and low-EMG tone, while (iv) paradoxical sleep had a low-amplitude, low-frequency signal with elevated theta power and low-EMG tone. Ube3a-del mice had significantly reduced b mean time in paradoxical sleep and d increased latencies to paradoxical sleep states, suggesting that deep sleep in deletion mice was not only shorter, but delayed compared to WT littermate controls. Additionally, Ube3a-del mice exhibited decreased mean time in c slow-wave sleep that when combined with the paradoxical sleep deficits resulted in lower h total sleep time compared to WT controls. *p < 0.05, Student’s t test between genotype