Development of an auditory stimulator synchronized with cortical EEG slow oscillation

Abstract

The slow oscillation (SO) of cortical EEG during deep sleep is involved in memory consolidation. Recently, it has been reported that auditory stimulation synchronized with spontaneous SO during sleep enhanced the SO and elevated performance of declarative memory in humans. However, detail properties including stimulus timing-dependency have not been clarified. In this study, to elucidate these properties, we developed an experimental system for mice that can generate auditory stimulus at arbitrary phase of SO. This system consists of two components; a microcomputer for real-time waveform analysis based on template matching and a DSP for auditory stimulus generation. Evaluation test using EEG signals recorded from the mouse neocortex during sleep demonstrated that the developed system works as designed. We will investigate phase-response characteristics of SOs and possible contribution to memory consolidation by animal experiments.