The science of dreams – Consciousness and lucid dreaming: the world’s leading expert challenges our misconceptions
Neurobiologists and cognitive scientists are currently engaged in new efforts to establish the brain basis of consciousness. Progress in brain imaging, quantitative recording of electrical activity produced by neurons within the human brain and in unit documentation in animals, have all contributed to our present knowledge. However, progress has been limited by the relative poverty of the paradigms used in these studies, many of which do not take subjective experience into account. One promising model, though problematical, is lucid dreaming.
Lucid dreaming is the rare but robust awareness that we are dreaming and that we are not really awake. It is paradoxical. In fact, lucid dreaming is an example of dissociation, one of the most fundamental features of normal and abnormal psychology. Moreover, the occurrence of this state is notably susceptible to pre-sleep autosuggestion. That is to say, the spontaneous incidence of lucid dreaming can be increased by training. Young subjects may not only learn to become lucid but can also perform intentional self-awakenings, and even institute plot control by introducing voluntary decision making into the normally involuntary dream experience.
Aside from its powerful psychedelic, therapeutic and entertainment value, lucid dreaming is an attractive phenomenon for scientific investigation within the area of consciousness studies. Lucid dreamers often claim that they can watch their dreams evolve and then alter their course as they see fit. If one believes these claims, it can be concluded that the human mind is capable of being in two states, waking and dreaming, at one time. For scientists, this means that it may be possible to measure the physiological correlates of three conscious states: waking, non-lucid dreaming and lucid dreaming. Since the three states are psychologically distinct, they should be physiologically distinct.
The first scholar to document lucidity extensively was the French aristocrat Marquis d’Hervey de Saint Denys. In 1867 he anonymously published Dreams and the Means of Directing Them. Like many of his contemporary Parisian colleagues, he was experimentally inclined and concerned with the mechanism of dreaming – also called by him “clichés souvenirs”, or snapshot memories. He was also concerned about the moral implications of this state of mind: if dreaming is involuntary then how a person could be legally accountable for his dreams.
In 1921, Mary Arnold-Forster described her personal experiments in Studies in Dreams. It contained a foreword by the distinguished Boston psychologist Morton Prince. Apparently unaware of the earlier work of Saint Denys, Arnold-Forster was principally concerned with determining what she could and could not do when dreaming lucidly. Like many other lucid dreamers, she taught herself to fly and thus to enter, at will, all of the rooms of her house, particularly enjoying flying down the stairs.
Following the discovery of REM (a period of sleep in which the activity of the brain’s neurons is most similar to that during waking hours, also called paradoxical sleep) by Aserinsky and Kleitman in 1953, an objective study of lucid dreaming was undertaken in earnest by K M Hearne in 1978. An early and still persisting problem was the difficulty that many normal subjects had in becoming lucid while sleeping in the laboratory. That meant that scientists were often tempted to study themselves or only a very few others. That fact naturally raised the suspicion of peers who demanded broader sampling.
During the 1980s, Stephen LaBerge convincingly demonstrated that lucidity always arose out of REM sleep and that subjects were able to signal that they were lucid by making a series of voluntary eye movements. His insistence that lucid dreaming occurred within REM invited controversy from critics who felt that his subjects might be fully awake. It now appears that LaBerge and his critics were both right. Lucid dreamers are both awake and dreaming which gives the revisitation of this phenomenon its new appeal to the emerging, still relatively new, science of consciousness.
How can the brain be in two different states at once? The answer to this question is that state dissociations are, in fact, quite commonplace. One part of the brain may be asleep while another is awake. In the case of sleep-walking the gait-generator (the part of the brain which controls walking) and navigational system of the brain stem may be fully functional while the cerebral cortex (the outer layer and most active part of the brain – also known as grey matter) is still in a stage of sleep. Sleep walkers, usually children or adolescents, are notoriously difficult to arouse. Just the opposite dissociation occurs in sleep paralysis when the dreamer wakes up from REM and is unable to move because of persistent REM sleep motor inhibition, which is where the part of the brain that controls movement is still asleep.
These and other normal dissociations show that the brain-mind is not always in one, and only one, state. Such cross-state fluidity helps us to understand many normal dissociations and opens the door to new models of psychopathology as well. Instead of the all-or-none categorical approach to mental illness taken by psychiatry from the 19th century to the present, we can now consider dimensional models such as the state space schema of AIM which was derived from animal experiments. AIM represents the cardinal syndromes of waking and sleep in a four dimensional array that easily accounts for the dissociations of normal and abnormal consciousness; the four dimensions being the independent values over time (T), activation (A), input-output gating or control (I), and modulation (M).
Consider hallucinosis (the mental state in which hallucinations occur). We know that dreaming is characterised by vivid visual percepts which, by formal definition, are hallucinations. Hallucinations also occur at sleep onset and on waking up. In each case, a symptom of major mental illness is experienced. But the subjects are not mentally ill. They are simply evincing normal state changes which are dissociative because such variables as A, I, and M do not change simultaneously. To hallucinate with our eyes open, we have only to run the REM-sleep dream-image generator in waking. When we hallucinate, we are in two states at once.
The best proof that lucid dreaming is a third state of consciousness, sandwiched in between waking and non-lucid dreaming, is empirical. The results of recent studies suggest that this is the case. However, how can we be sure that an experimental subject is asleep when lucidity is signalled by a set of voluntary eye movements? How do we know that the subject has not woken up? It is helpful to note that inhibition of muscle tone persists in lucid dreaming, but a more confident answer to this question requires a stretch. It is that the subject is both awake and asleep with different parts of the brain in different states at the same time.
Lucid dreaming is an unusual state characterised by elements of both waking and dreaming. It is a condition which has attracted the attention of scientists with an interest in further specifying the brain basis of consciousness. Quantitative electroencephalogram (EEG – used to map electrical activity in the brain) studies indicate that an extra 40 Hz power in brain activity is needed during sleeping for lucid dreaming. In addition, brain imaging research has shown that the regional activation pattern in lucid dreaming correlates with those frontal brain areas known to be more highly developed in humans than in monkeys. To become aware that one is dreaming, it would appear to be important to ratchet up 40 Hz power of frontal brain activity and thus to turn on a distributed network that is normally active during waking consciousness.
By means of pre-sleep autosuggestion, it could be possible to induce lucidity while dreaming. This is an interpretation of earth-shaking importance to our current concepts of understanding consciousness and therefore of mental health and illness. Among other things, lucid dreaming provides a new model of consciousness that challenges previous static divisions, and relations, of awake and dreaming states; that you can only be either awake or sleep. Lucid dreaming provides a new model that proves that the brain can also be in a middle state. This suggests that there is no clear division between being awake or sleep but more of a continuum state. As a result, mental health and illnesses could be understood as a flux, balanced or not, between these states. It portrays the mind as a constant flow of information – a continuum of thoughts, dreams and actions. This suggests that we may have a handle on insight and that we can train ourselves to incorporate these different aspects of our mind via suggestion. If that is so, then lucid dreaming could move from its marginal and tenuous place at the fringe of psychophysiology to centre stage in the emerging science of consciousness. Lucid dreaming may, in turn, help consciousness science to effect revolutionary changes in psychology and to help unlock some of the mind’s greatest mysteries.
by Allan Hobson
From the Glass Archive – Issue Five – Dreams