David Kahn, Harvard Medical School, Cambridge, MA
Allan Combs, University of North Carolina, Asheville, NC
Stanley Krippner, Saybrook Graduate School, San Francisco

Abstract: This paper argues that dream experiences owe both their structure and meaning to stochastic self-organizing properties of the brain during sleep. Several lines of evidence support the notion that the dreaming brain can be understood as a process system that exhibits chaos-like stochastic properties that are highly sensitive to internal influences. This sensitivity is due, first, to the fact that the dreaming brain gates out external input, thus operating without the stabilizing influences of waking feedback. Second, the pre-frontal cortex in both REM and non-REM (NREM) sleep is only minimally activated, thus the brain operates with weakened volition, reduced logic, and diminished self-reflection. Third, there is a reduction of neuromodulatory inhibition during sleep, which is most pronounced during REM sleep, allowing the brain to respond to minute internal stimulation. Finally, the REM sleeping brain is subject to powerful intermittent cholinergic PGO activity that may provide vigorous stimulation for complex dream activity. Taken in overview, this conception of dreaming offers a common meeting ground for brain-based studies of dreaming and psychological dream theory.

Keywords: brain, consciousness, dream, chaos, stochastic process, self-organization, REM sleep, NREM sleep