Behavioral and Brain Sciences

Dreaming and the brain: Toward a cognitive neuroscience of conscious states

J. Allan Hobson a1, Edward F. Pace-Schott a1 and Robert Stickgold a1
a1 Laboratory of Neurophysiology, Department of Psychiatry, Harvard Medical School, Massachusetts Mental Health Center, Boston, MA 02115


Sleep researchers in different disciplines disagree about how fully dreaming can be explained in terms of brain physiology. Debate has focused on whether REM sleep dreaming is qualitatively different from nonREM (NREM) sleep and waking. A review of psychophysiological studies shows clear quantitative differences between REM and NREM mentation and between REM and waking mentation. Recent neuroimaging and neurophysiological studies also differentiate REM, NREM, and waking in features with phenomenological implications. Both evidence and theory suggest that there are isomorphisms between the phenomenology and the physiology of dreams. We present a three-dimensional model with specific examples from normally and abnormally changing conscious states.

Key Words: consciousness; dreaming; neuroimaging; neuromodulation; NREM; phenomenology; qualia; REM; sleep.