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."
Was this article helpful?