Fig. 5: Modulation of slow oscillation (SO) activity by auditory stimulation in N2 sleep.

a Extraction of SOs from the continuous N2 sleep data and the corresponding mean SO in all experimental conditions at electrode Cz for one exemplar subject. b Grand average (Nā=ā23) SO waveforms at electrode Cz centered around sound onset and R peak in the synch, asynch, isoch, and baseline conditions during N2 sleep. c Distribution and single subject sound-to-SO median latency and R peak-to-SO median latency with statistically significant differences (pā<ā0.05; black vertical lines) across conditions. SO peaks are more likely to occur closer to the sound onset in the synch and isoch conditions than in the asynch conditions. These results are not trivially driven by a temporal proximity between R peaks and SO peaks in the synch condition. n.s.ā=ānot significant.