Consciousness: Altered States

Oliver W Hill Jr. Psychology Basics. Editor: Nancy A Piotrowski. Volume 1. Pasadena, CA: Salem Press, 2005.

The great psychologist William James, in his 1890 textbook The Principles of Psychology, made the following now-famous observation regarding states of consciousness: “Our normal waking consciousness, rational consciousness as we call it, is but one special type of consciousness, whilst all about it, parted from it by the filmiest of screens, there lie potential forms of consciousness entirely different.” James went on to say that the understanding of human psychological functioning would never be complete until these alternate states were addressed. Most psychologists would now acknowledge that a person’s normal waking consciousness is readily subject to changes. These changes are referred to as altered states of consciousness. What constitutes a genuine altered state and how many such states may exist are both subjects of some controversy.

States of consciousness have always been central to the attempt to understand human nature. For example, every society of which any record exists has possessed both chemical and nonchemical means of altering consciousness.

From a historical point of view, Sigmund Freud (1856-1939) may have done more than any other theorist to stimulate interest in states of consciousness. Freud’s psychoanalytic theory of personality held that there were three primary levels of consciousness: consciousness, preconsciousness, and unconsciousness. The conscious level includes mental activities of which one is unaware. The preconscious level consists of mental material of which one is currently unaware but that can be voluntarily recalled—roughly equivalent to memory. The unconscious level, which held the greatest interest for Freud, contains thoughts, feelings, memories, and drives that are blocked from awareness because they are unpleasant or arouse anxiety. In addition to his interest in these three levels of consciousness, Freud’s interest in altered states at various points in his career was manifested in investigations of cocaine, hypnosis, and the analysis and interpretation of dreams.

In the early twentieth century, with the growth of behaviorism (which insisted that in order to be a science, psychology should confine itself to investigating only objective, observable behavior), the study of altered states of consciousness fell out of favor. Events in the larger culture during the 1960’s and 1970’s, however, helped stimulate interest in altered states within psychology. During this period, efforts to expand consciousness by means of drugs, meditation, Eastern religious practice, and new ways of relating to oneself and others led to the active study of altered states of consciousness. The attempts of psychologists to study altered states of experience will perhaps be viewed in the future as a landmark in the development of psychology as a science. The willingness of psychology to explore the novel realms that altered states represent may help to expand the understanding of both consciousness and reality.

Variations in Consciousness

Physiological psychologist Karl Pribram lists the following states of consciousness: states of ordinary perceptual awareness; states of self-consciousness; dream states; hypnagogic and hypnopompic states (the transition states, characterized by vivid dreamlike imagery, that occur as one goes into and comes out of sleep); ecstatic states (such as the orgiastic experience); socially induced trance or trancelike states; drug-induced states; social role states; linguistic states (for example, a multilingual person thinking in one, rather than another, language); translational states (as when one linguistic universe is being recorded or translated in another); ordinary transcendental states (such as those experienced by an author in the throes of creative composition); extraordinary transcendental states that are achieved by special techniques; other extraordinary states (such as those that allow “extrasensory awareness”); meditational states; dissociated states, as in the case of pathological multiple personality; and psychomotor states manifest in temporal-lobe epilepsies. To that list could be added the following additional states: sleep; the hyperalert state, characterized by increased vigilance while one is awake; the lethargic state, characterized by dulled, sluggish mental activity; states of hysteria, with intense feeling and overpowering emotion; regressive states, such as senility; daydreaming with rapidly occurring thoughts that bear little relation to the external environment; coma; sleep deprivation; sensory overload or deprivation; and prolonged strenuous exercise. This list is by no means exhaustive.

Some of these states clearly represent greater degrees of alteration of the “normal” consciousness than others. There is, however, no universal agreement on what constitutes the normal state of consciousness. Charles Tart and other authors have suggested that what is usually called “normal” consciousness is not a natural, given state but a construction based mainly on cultural values and inputs. In any case, some altered states of consciousness are experienced on a daily basis by everyone, while others are much more rare and may require great effort or special circumstances to achieve.

Influences on Altered Consciousness

Some alterations in conscious functions are induced by daily changes in biological rhythms. Bodily events that occur in roughly a twenty-four-hour cycle are referred to as circadian rhythms, from the Latin circa (“about”) and dies (“day”). It is thought that these cycles are created by natural events, such as the light-dark cycle, and by other cues in the daily routine, such as mealtimes. The sleeping-waking cycle is the major circadian rhythm, but there are others, such as fluctuations in body temperature. This daily temperature cycle appears to be directly related to levels of mental activity. When all external cues are removed, circadian rhythms extend to about twenty-five hours. As a result of prolonged isolation, the cycle can become completely distorted, with periods of up to forty hours of waking followed by periods of up to twenty-two hours of sleep. When the change is gradual in this way, the individual has a distorted sense of time and believes that he or she is experiencing normal periods of sleep and waking. Abrupt changes in circadian rhythms, as when one crosses several time zones, are what lead to that sleepy, uncomfortable feeling known as jet lag.

In addition to biological rhythms, there are other regular daily variations in consciousness. On the way to sleep each night, people enter a kind of “twilight” period known as the hypnagogic state. The state of consciousness that is entered immediately before waking is called the hypnopompic state. In both these states, one is partially asleep and partially continuing to process environmental stimuli. Both are characterized by vivid imagery, and many people have reported creative insight during these periods.

Stages of Sleep

Sleep itself is not a unified state but consists of five distinct stages: one stage of rapid eye movement (REM) sleep and four stages of nonrapid eye movement (NREM) sleep. During a typical night’s sleep, one moves in and out of these stages four or five times. REM sleep is primarily associated with periods of dreaming. Sleeping subjects awakened during a period of REM sleep report having just experienced a dream about 80 percent of the time, compared with less than 10 percent when NREM sleep is interrupted. Psychologists are still unclear on exactly why humans need to sleep, but the need for periods of REM sleep might be part of the reason. When sleeping subjects are deprived of REM sleep (and their NREM sleep is undisturbed), they often show many of the symptoms of not having slept at all. Also, when later given the opportunity for uninterrupted sleep, they spend a greater percentage of time in the REM stage, as if making up for the lost REM sleep (this is referred to as the REM-rebound effect). The REM-rebound effect is lessened if the individual is encouraged to engage in an increased amount of daydreaming, which indicates a possible connection between day and night dreams.

Psychoactive Drugs

The use of psychoactive drugs is a common method for altering consciousness. These drugs are chemical substances that act on the brain to create psychological effects and are typically classified as depressants, stimulants, narcotics (opiates), hallucinogens, or antipsychotics. Several drugs, such as nicotine, caffeine, and alcohol, are so much a part of the lifestyle in modern society that users may not even think of them as drugs. The use of many psychoactive drugs can lead to physical or psychological dependence or addiction, as the body/mind develops a physiological/psychological need for the drug. The body can also build up a tolerance for a drug, which means that higher and higher doses are necessary to produce the same effects. Once addiction has been established, discontinuing the use of the drug can lead to withdrawal symptoms, such as nausea, fever, convulsions, and hallucinations, among others, which can sometimes be fatal.

The type of altered state produced by a psychoactive drug depends on the class to which the drug belongs. Depressants, such as alcohol, barbiturates, and tranquilizers, depress central nervous system functioning and usually produce relaxation, anxiety reduction, and—eventually—sleep. Narcotics (opiates), such as heroin, morphine, and codeine, depress activity in some areas of the cortex but create excitation in others, producing feelings of euphoria and providing relief from pain. Stimulants, such as amphetamines, cocaine, caffeine, and nicotine, stimulate central nervous system activity, producing feeling of alertness and euphoria and lack of appetite. Hallucinogens, such as lysergic acid diethylamide (LSD), mescaline, and psilocybin, can produce hallucinations, delusions, exhilaration, and, in some cases, quasi-mystical experiences.

Hypnosis and Meditation

Two popular nonchemical techniques for altering consciousness are hypnosis and meditation. Hypnosis was first discovered in the eighteenth century by Franz Mesmer, and its use has been marked by controversy ever since. An altered state is induced in hypnosis by the suggestive instructions of the hypnotist, usually involving progressive relaxation. The hypnotized subject often appears to be asleep but remains alert inside, exhibiting varying degrees of responsiveness to the suggestions of the hypnotist. Only about 10 percent of the population can enter the deepest hypnotic state, while another 10 percent cannot be hypnotized at all. The rest of the population can achieve some degree of hypnotic induction. Psychologists argue about whether hypnosis is a genuine altered state or simply a form of role playing.

There is less controversy regarding meditation as a true altered state. Since the mid-1960’s, there has been extensive research on the physiological changes that occur during meditation. Some of the findings include a decrease in oxygen consumption of 16 percent during meditation (compared with an 8 percent drop during the deepest stage of sleep), a cardiac output decrease of 25 percent, and an average slowing of the heart rate by five beats per minute. During meditation, electroencephalogram (EEG) patterns are dominated by the alpha rhythm, which has been associated with relaxation. An EEG is a graphic recording of the electrical activity of brain waves. Researchers R. K. Wallace and Herbert Benson believed that there was sufficient physiological evidence to justify calling the meditative state a “fourth major state of consciousness” (along with waking, dreaming, and sleeping), which they termed a “wakeful, hypometabolic [reduced metabolic activity] state.” Beginning meditators usually report feelings of relaxation and “ordinary thoughts,” while advanced practitioners sometimes report transcendental experiences of “consciousness without content.”

Applications of Hypnosis

Research on altered states of consciousness has led to many benefits. The analgesic properties of hypnosis were verified in research conducted by Ernest Hilgard at Stanford University. He found that hypnotic suggestion could be used to reduce or eliminate experimentally induced pain. Even though subjects were not consciously aware of the pain, Hilgard found that, with the right questions, he could uncover a “hidden observer,” a dissociated aspect of the subject’s conscious awareness that did monitor the feelings of pain. Hilgard reports that hypnotic relief from pain has been reported for the chronic pain of arthritis, nerve damage, migraine headaches, and cancer. For individuals who are unable to be anesthetized because of allergic reactions or fear of needles, hypnosis is often used as an effective substitute for the control of pain. It has been effectively applied in cases involving dental work, childbirth, burns, abdominal surgery, and spinal taps. Hypnotic suggestion has also been effective in reducing the nausea associated with cancer chemotherapy.

The use of hypnosis to recover forgotten memories is much more controversial. One dramatic phenomenon displayed with certain hypnotic subjects is age regression, in which the individual not only is able to recall vividly childhood memories but also seems to reenact behaviors from childhood, including body postures, voice, and handwriting characteristics of a given age. There is no way of knowing, however, whether this represents true recall or is simply a type of fantasy and role playing. Hypnosis has also been used to enhance the memories of crime witnesses in court proceedings. There is evidence, however, that actual recall does not become more accurate and that the witness may be unintentionally influenced by the suggestions of the hypnotist, which could lead to inaccuracies and distortions in the “remembered” events. For this reason, courts in many states automatically disqualify testimony obtained by means of hypnosis.

Benefits of Meditation

Research on the physiological effects of meditation led to the application of meditative techniques as a treatment to combat stress-related illnesses. Meditators have often experienced significant decreases in such problems as general anxiety, high blood pressure, alcoholism, drug addiction, insomnia, and other stress-related problems. Researchers have also found that the scores of meditators on various psychological tests have indicated general mental health, self-esteem, and social openness. Many psychologists argue, however, that these effects are not unique to meditation and can be produced by means of other relaxation techniques. Meditation researcher Robert Ornstein has suggested that the long-term practice of meditation may induce a relative shift in hemispheric dominance in the brain from the left hemisphere, which is associated with such linear processes as language and logical reasoning, to the right hemisphere, which is associated with nonlinear processes such as music perception and spatial reasoning. Consistent with this idea are findings that meditators are better on certain right-hemispheric tasks such as remembering musical tones but worse on verbal problem-solving tasks that involve the left hemisphere.


Early research on advanced meditators in India indicated that they could exhibit control over what are normally autonomic processes in the body—for example, speeding up or slowing down the heart rate at will, stopping the heart for up to seventeen seconds, controlling blood flow to different areas of the body, and controlling brain-wave patterns at will. At first, these results were met with skepticism, but it is now known that humans and animals can learn to control previously involuntary processes by using a technique known as biofeedback. Through biofeedback training, an individual who is connected to a special measuring device can monitor autonomic events such as blood pressure, skin temperature, and muscle tension. Having this information can allow the individual gradually to gain control over these autonomic processes. Biofeedback techniques have been applied to an enormous variety of clinical problems. EEG biofeedback, for example, has been used to train epileptics to emit brain-wave patterns that are incompatible with those that occur during brain seizures. Other disorders that have been successfully treated by means of biofeedback include cardiac disorders, high blood pressure, tension headaches, anxiety, and neuromuscular disorders such as cerebral palsy.

Sensory Deprivation

Other applications have grown out of research on altered states of consciousness produced by restricting sensory stimulation from the environment. Researchers in the 1950’s completed extensive studies on the effects of prolonged sensory deprivation. Subjects placed in soundproof isolation chambers with translucent goggles to eliminate vision and padded arm tubes to minimize touch sensation often experienced negative psychological effects after about a day. Most subjects suffered from extreme boredom, slowed reaction time, and impaired problem-solving ability. Some subjects reacted to sensory deprivation by creating their own internally generated sights and sounds in the form of hallucinations. These results led to the institution of special procedures to help reduce the effects of sensory deprivation in certain occupations; for example, airline pilots on long night flights, astronauts living for prolonged periods in tiny space capsules, and individuals working in isolated weather stations. A controlled form of sensory deprivation, known as restricted environmental stimulation therapy (REST), has been used to reduce the effects of overarousal and hyperactivity. REST sessions usually involve floating in heavily salted warm water in a dark, soundproof tank. Most subjects find this floating sensation very pleasant, and there have been many reports of long-term reductions in high blood pressure and other stress-related problems.

Argument for State-Specific Sciences

Although traditional scientific methods are poorly suited to the study of consciousness, many beneficial tools that can be used to measure the physiological correlation of altered states, such as the electroencephalograph, have been developed as an outgrowth of the study of states of consciousness.

Psychologist Charles Tart suggested the creation of state-specific sciences. In reaching this conclusion, he argues that any particular state of consciousness (including ordinary waking) is a semiarbitrary construction—a specialized tool that is useful for some things but not for others and that contains large numbers of structures shaped by a particular group’s value judgments. Thus, science is observation and conceptualization carried out within the highly selective framework provided by a culturally determined ordinary state of consciousness. Tart suggests that, as altered states of consciousness often represent radically different ways of organizing observations and reworking conceptualizations of the universe (including oneself), if the scientific method were applied to developing sciences within various states of consciousness, there would be sciences based on radically different perceptions, logics, and communications, and thus science as a whole would gain new perspectives that would complement the existing one.

Regardless of whether this suggestion is taken seriously, it is clear that the study of states of consciousness has achieved legitimacy in scientific psychology. The investigation so far has revealed that human consciousness is much more diverse and varied than many psychologists previously believed.

Sources for Further Study

Flannagan, Owen J. Dreaming Souls: Sleep, Dreams, and the Evolution of the Mind. New York: Oxford University Press, 1999. A professor of philosophy, experimental psychology, and neurobiology proposes that dreams are an unplanned side effect of the evolution of a human mind designed to “have experiences.” Reviews current research and theory on the nature and functions of dreaming as well as presenting his own thesis.

Hilgard, Ernest Ropiequet. Divided Consciousness: Multiple Controls in Human Thought and Action. Expanded ed. New York: John Wiley & Sons, 1986. A discussion of consciousness by one of the most respected experimental psychologists. Included are discussions on the hidden observer phenomenon in hypnosis and on other dissociation phenomena such as multiple personality, amnesia, and fugue states.

Hobson, J. Allen. The Dream Drugstore: Chemically Altered States of Consciousness. Cambridge, Mass.: MIT Press, 2001. Discusses the natural and voluntarily altered chemistry of the brain and its effects on human consciousness. Hobson addresses the modern reliance on antidepressants such as Prozac as well as the “recreational” drugs of underground culture and presents the possible connections between dreaming states, drug-induced states, and mental illnesses in a nonjudgmental fashion.

Ornstein, Robert Evan, ed. The Nature of Human Consciousness. San Francisco: W. H. Freeman, 1973. This anthology contains essays by many of the pioneers in the psychological study of altered states of consciousness, including Carl Jung, Roberto Assagioli, Arthur Deikman, and many others. Topics include meditative states, psychosynthesis, Sufism, and synchronicity.

――――――――――. The Psychology of Consciousness. 2d rev. ed. New York: Penguin Books, 1986. This is considered a classic text on altered states of consciousness. It provides in-depth discussions of the psychology of meditation and the relationship of altered states to hemispheric differences in the brain.

Ward, Colleen A., ed. Altered States of Consciousness and Mental Health: A Cross-cultural Perspective. Thousand Oaks, Calif.: Sage, 1989. A collection of papers assessing the mental health value and use of altered states of consciousness from a non-Western perspective.

Wolman, Benjamin B., and Montague Ullman, ed. Handbook of States of Consciousness. New York: Van Nostrand Reinhold, 1986. This is an excellent sourcebook on psychological theory and research on altered states of consciousness. Discusses, in addition to the topics covered in this article, trance states, lucid dreams, ultradian rhythms, and many other subjects.