The Neural Basis of Consciousness During Evening Naps Measured by MEG: A Registered Report
Chikayo Hemmi, Angus Leung, Jennifer Windt, Yuki Motomura, Hiroshige Takeichi, Mochine Ishii, Takashi Tsutsumi, Yuri Kawabata, Naoko Takahashi, Shota Hosogai, Hiroshi Shigeto, Koichi Hagiwara, Naotsugu Tsuchiya, Chihiro Hiramatsu
Summary
AI-generated from the abstractThe neural correlates of dreaming remain uncertain, especially regarding which brain regions and frequency bands reliably reflect conscious experience during sleep. This registered report describes a study that will use magnetoencephalography (MEG) during evening naps with a targeted serial-awakening paradigm to test whether previously reported EEG-based correlates of dreaming generalize to MEG. Pilot data from one participant supported hypotheses about low-frequency power across frontal and posterior regions but not high-frequency power; another participant provided insufficient evidence. An independent analysis team will test the pre-specified hypotheses on the remaining 10 participants who meet inclusion criteria.
Study at a glance
| Characteristics | Registered report |
|---|---|
| Sample size | 10 |
| Population | Participants who meet inclusion criteria |
| Key finding | Pilot data from one participant were consistent with hypotheses concerning low-frequency power across regions but not with those related to high-frequency power; another participant provided insufficient evidence for all hypotheses. |
Abstract
Dream experiences during sleep provide an excellent opportunity to investigate the neural basis of consciousness. Previous studies have examined the neural correlates of dreaming using electroencephalography (EEG), focusing on spectral power in specific frequency bands. However, findings have been inconsistent, particularly regarding the spatiotemporal characteristics of these correlates, raising questions about whether spectral power in specific brain regions and frequency bands reliably reflects dreaming. In this study, we investigate whether neural correlates reported in a highly influential EEG study generalize to consciousness during evening naps, measured using magnetoencephalography (MEG), which offers more accurate source reconstruction than EEG. In Stage 1, the data acquisition team completed data collection, obtaining MEG data and subjective reports using a targeted serial-awakening paradigm. We test hypotheses regarding the relationship between low- and high-frequency neural power in frontal and posterior regions and conscious experience. We defined data inclusion and exclusion criteria and established pre-specified analytical procedures based on data from two participants. The pilot results from one participant were consistent with the hypotheses concerning low-frequency power across regions, but not with those related to high-frequency power. The other participant provided insufficient evidence for all hypotheses. In Stage 2, an independent analysis team will conduct group-level hypothesis testing according to the pre-specified procedure, using data from the remaining unanalyzed participants (N = 10) who meet the inclusion criteria.