Neural correlates of dream lucidity obtained from contrasting lucid versus non-lucid REM sleep: a combined EEG/fMRI case study.

STUDY OBJECTIVES: To investigate the neural correlates of lucid dreaming.

DESIGN: Parallel EEG/fMRI recordings of night sleep.

SETTING: Sleep laboratory and fMRI facilities.

PARTICIPANTS: Four experienced lucid dreamers.

INTERVENTIONS: N/A.

MEASUREMENTS AND RESULTS: Out of 4 participants, one subject had 2 episodes of verified lucid REM sleep of sufficient length to be analyzed by fMRI. During lucid dreaming the bilateral precuneus, cuneus, parietal lobules, and prefrontal and occipito-temporal cortices activated strongly as compared with non-lucid REM sleep.

CONCLUSIONS: In line with recent EEG data, lucid dreaming was associated with a reactivation of areas which are normally deactivated during REM sleep. This pattern of activity can explain the recovery of reflective cognitive capabilities that are the hallmark of lucid dreaming.