Abstract of talk to be presented at the
Toward a Science of Consciousness Conference, Tucson, April 9, 1996
DREAMING AND CONSCIOUSNESS
Stephen LaBerge, Ph.D.
Whether awake or asleep, our consciousness functions as a model of the
world constructed by the brain from the best available sources of
information. During waking conditions, this model is derived primarily
from sensory input, which provides the most current information about
present circumstances, and secondarily from contextual and motivational
information. While we sleep, very little sensory input is available, so
the world model we experience is constructed from what remains,
contextual information from our lives, that is, expectations derived from
past experience, and motivations (e.g., wishes, as Freud observed, but
also fears). As a result, the content of our dreams is largely determined
by what we fear, hope for, and expect (1, 2).
From this perspective, dreaming can be viewed as the special case of
perception without the constraints of external sensory input. Conversely,
perception can be viewed as the special case of dreaming constrained by
sensory input (1-3). Whichever way one looks at it, understanding
dreaming is central to understanding consciousness.
Theories of consciousness that do not account for dreaming must be
regarded as incomplete, and theories that are contradicted by the findings
of phenomenological and psychophysiological studies on dreaming must be
wrong. For example, the behaviorist assumption that "the brain is
stimulated always and only from the outside by a sense organ process" (4)
cannot explain dreams; likewise, for the assumption that consciousness is
the direct or exclusive product of sensory input.
Dreaming experience is commonly viewed as qualitatively distinct from
waking experience. Dreams are often believed to be characterized by lack
of reflection and inability to act deliberately and with intention.
However, this view has not been based on equivalent measurements of
waking and dreaming state experiences. To achieve equivalence, it is
necessary to evaluate waking experience retrospectively, in the same way
that dreams are evaluated. In a recent study of this type (5), we found
that compared to waking experiences, dreaming was more likely to contain
public self consciousness and emotion, and less likely to contain
deliberate choice. But it is notable that significant differences between
dreaming and waking were not evident for other cognitive activities, and
none of the measured cognitive functions were typically absent or rare in
dreams. In particular, nearly identical levels of reflection were
reported in both states.
Although we are not usually explicitly aware of the fact that we are
dreaming while we are dreaming, at times a remarkable exception occurs,
and we become reflective enough to become conscious that we are dreaming.
During such "lucid" dreams it is possible to freely remember the
circumstances of waking life, to think clearly, and to act deliberately
upon reflection or in accordance with plans decided upon before sleep,
all while experiencing a dream world that seems vividly real (1, 6). A
series of studies to be summarized demonstrates that lucid dreamers can
remember to perform predetermined actions and signal to the laboratory,
allowing the derivation of precise psychophysiological correlations and
the methodical testing of hypotheses regarding consciousness in sleep.
1. LaBerge, S.(1985). Lucid dreaming. Los Angeles: J. P. Tarcher.
2. LaBerge, S. & Rheingold, H. (1990). Exploring the world of lucid
dreaming. New York: Ballantine.
3. Llinas, R. & Pare, D. (1991). Of dreaming and wakefulness.
Neuroscience, 44, 521-35.
4. Watson, J. (1928). The ways of behaviorism. New York: Harper. p. 75
5. LaBerge, S., Kahan, T. & Levitan, L. (1995). Cognition in dreaming and
waking. Sleep Research, 24A, 239.
6. LaBerge, S. (1990). Lucid dreaming: Psychophysiological studies of
consciousness during REM sleep. In R.R. Bootsen, J.F. Kihlstrom, & D.L.
Schacter (Eds.), Sleep and Cognition. Washington, D.C.: American
Psychological Association (pp. 109-126).