by Isaac Asimov
Other chimpanzees were so taught by others—and young gorillas, too. And, with that, came controversy. Were the apes actually communicating creatively, or were they merely responding mechanically in conditioned-reflex fashion?
Those who taught the apes had many anecdotes of their charges inventing new and creative combinations of symbols, but such things are dismissed as unconvincing by critics, or as uncertain. The controversy will undoubtedly continue.
The power of conditioning has turned out to be greater than had been expected, in fact, even in human beings. For a long time it had been assumed that certain body functions—such as heartbeat, blood pressure, and intestinal contractions—were essentially under the control of the autonomic nervous system and therefore beyond conscious control. There were catches, of course. A man adept at yoga can produce effects on his heartbeat by control of chest muscles, but that is no more significant than stopping the blood flow through a wrist artery by applying thumb pressure. Again, one can make one’s heart beat faster by fantasying a state of anxiety, but that is the conscious manipulation of the autonomic nervous system. Is it possible simply to will the heart to beat faster or the blood pressure to rise without extreme manipulation of either the muscles or the mind?
The American psychologist Neal Elgar Miller and his co-workers carried out conditioning experiments, in the early 1960s, where rats were rewarded when they happened to increase their blood pressure for any reason, or when their heartbeat was increased or decreased. Eventually, for the sake of the reward, they learned to perform voluntarily a change effected by the autonomic nervous system—just as they might learn to press a lever, and for the same purpose.
At least one experimental program, using human volunteers (male) who were rewarded by flashes of light revealing photographs of nude girls, demonstrated the volunteers’ ability to produce increases or decreases in blood pressure in response. The volunteers did not know what was expected of them in order to produce the flashing light—and the nude—but just found that, as time went along, they caught the desired glimpses more often.
More systematic experimentation showed that if people were made aware, at all times, of some property they are ordinarily unaware of—say, blood pressure, heart rate, or skin temperature—they can, through a voluntary effort (in some fashion not easily defined), change the value. This process is called biofeedback.
There were hopes at first that biofeedback might accomplish, more efficiently and easily, some of the claims of the accomplishments of Eastern mystics: that it might control or ameliorate some otherwise intransigent metabolic disorders. These hopes seem to have faded in the last decade or so.
THE BIOLOGICAL CLOCK
There are additional subtleties to the autonomic body controls which had earlier gone unsuspected. Since living organisms are subjected to natural rhythms—the ebb and flow of the tides, the somewhat slower alternation of day and night, the still slower swing of the seasons—it is not surprising that they themselves respond rhythmically. Trees shed their leaves in fall and bud in the spring; humans grow sleepy at night and rouse themselves at dawn.
What did not come to be fully appreciated until lately is the complexity and multiplicity of the rhythmic responses, and their automatic nature, which persists even in the absence of the environmental rhythm.
Thus, the leaves of plants rise and fall in a daylong rhythm to match the coming and going of the sun. This is made apparent by time-lapse photography. Seedlings grown in darkness showed no such cycle, but the potentiality was there. One exposure to light—one only—was enough to convert that potentiality into actuality. The rhythm then began, and it continued even if the light was cut off again. From plant to plant, the exact period of rhythm varied—anywhere from 24 to 26 hours in the absence of light—but it was always about 24 hours, under the regulating effect of the sun. A 20-hour cycle could be established if artificial light were used on a 10-hour-on and 10-hour-off cycle, but as soon as the light was turned off altogether, the about-24-hour rhythm reestablished itself.
This daily rhythm, a kind of biological clock that works even in the absence of outside hints, permeates all life. Franz Halberg of the University of Minnesota named it circadian rhythm, from the Latin circa dies, meaning “about a day.”
Human beings are not immune to such rhythms. Men and women have voluntarily lived for months at a time in caves where they separated themselves from any time-telling mechanism and had no idea whether it was night or day outside. They soon lost all track of time and ate and slept rather erratically.
However, they also noted their temperature, pulse, blood pressure, and brain waves, and sent these and other measurements to the surface, where observers kept trade of them in connection with time. It turned out that, however time-confused the cave dwellers were, their bodily rhythm was not. The rhythm remained stubbornly at a period of about a day, with all measurements rising and falling regularly, through all the stay in the cave.
This is by no means only an abstract matter. In nature, the earth’s rotation remains steady, and the alternation of day and night remains constant and beyond human interference—but only if you remain in the same spot on earth or only shift north or south. If you travel east or west for long distances and quite rapidly, however, you change the time of day. You may land in Japan at lunchtime (for Japanese) when your biological clock tells you it is time to go to bed. The jet-age traveler often has difficulty matching his activity to that of the at-home people surrounding him. If he does so—with his pattern of hormone-secretion, for instance, not matching the pattern of his activity—he will be tired and inefficient, suffering from jet fatigue, or jet lag.
Less dramatically, the ability of an organism to withstand a dose of X rays or various types of medication often depends on the setting of the biological clock. It may well be that medical treatment ought to vary with the time of day or, for maximum effect and minimum side effect, be restricted to one particular time of day.
What keeps the biological clock so well regulated? Suspicion in this respect has fallen upon the pineal gland (see chapter 15). In some reptiles, the pineal gland is particularly well developed and seems to be similar in structure to the eye. In the tuatara, a lizardlike reptile that is the last surviving species of its order and is found only on some small islands off New Zealand, the pineal eye is a skin-covered patch on top of its skull, particularly prominent for about six months after birth and definitely sensitive to light.
The pineal gland does not “see” in the ordinary sense of the word, but may produce some chemical that rises and falls in rhythmic response to the coming and going of light. It thus may regulate the biological clock and do so even after light ceases to be periodic (having learned its chemical lesson by a kind of conditioning).
But then how does the pineal gland work in mammals, where it is no longer located just under the skin at the top of the head but is buried deep in the center of the brain? Can there be something more penetrating than lightsomething that is rhythmic in the same sense? There are speculations that cosmic rays might be the answer. These have a circadian rhythm of their own, thanks to Earth’s magnetic field and the solar wind, and perhaps this force is the external regulator.
Even if the external regulator is found, is the internal biological clock something that can be identified? Is there some chemical reaction in the body that rises and falls in a circadian rhythm and that controls all the other rhythms? Is there some “master reaction” that we can tab as the biological clock? If so, it has not yet been found.
PROBING HUMAN BEHAVIOR
It does not seem likely, however, that we are ever going to pin anything as complex as life into complete determinism. It is easy to be deterministic about something like the replication of nucleic acids, and yet environmental factors introduce errors that result in mutations and evolution. Nor is it conceivable that the course of evolution can be predicted in detail.
More fundamentally, we know from quantum mechanics that there are
indeterminacies and uncertainties inherent in the behavior of objects; and that the lighter the objects are and the less massive, the greater the indeterminacies. The behavior of electrons is, in some ways, unpredictable, and there are arguments to the effect that certain properties of electrons cannot be known until they are measured. It may even be that the state of the universe is, in a certain subtle way, defined at each instant of time by the observations and measurements made by human beings. (This is called the anthropic principle from the Greek word for “human being.”)
It is easy to see that there may be times when the course of human behavior or a human decision (or even perhaps those of lower animals) may rest upon the indeterminate motion of an electron somewhere in the body. This would, in principle, wreck determinism, but it would not establish free will either. It would, instead, introduce a random factor, which may well be harder to understand than either.
But not necessarily harder to handle. Random factors can be allowed for if there are enough such events. Individual gas molecules move about in random fashion; but in any ordinary quantity of gas, there are so many molecules that the randomness cancels out, and the gas laws will apply with great precision to such properties as temperature, pressure, and volume.
We have not come to this yet, however, and there have, instead, been attempts to attack human behavior by methods that are themselves highly intuitive and as difficult to handle as the behavior they attempt to deal with.
These methods can be traced back nearly two centuries to an Austrian physician, Franz Anton Mesmer, who became the sensation of Europe for his experiments with a powerful tool for probing human behavior. He used magnets at first, and then his hands only, obtaining his effects by what he called animal magnetism (soon renamed mesmerism): he would put a patient into a trance and pronounce the patient cured of his illness. Mesmer may well have produced some cures (since some disorders can be treated by suggestion) and gained many ardent followers, including the Marquis de Lafayette, fresh from his American triumph. However, Mesmer, an ardent astrologer and all-round mystic, was investigated skeptically but fairly by a committee, which included Lavoisier and Benjamin Franklin, and was then denounced as a fake and eventually retired in disgrace.
Nevertheless, he had started something. In the 1850s a British surgeon named James Braid revived hypnotism (he was the first to use this term in place of mesmerism) as a medical device, and other physicians also took it up. Among them was a Viennese doctor named Josef Breuer, who in the 1880s began to use hypnosis specifically for mental and emotional disorders.
Hypnotism (Greek for “putting to sleep”) had been known, of course, since ancient times and had often been used by mystics. But Breuer and others now began to interpret its effects as evidence of the existence of an unconscious level of the mind. Motivations of which the individual was unaware were buried there, and they could be brought to light by hypnosis. It was tempting to suppose that these motivations were suppressed from the conscious mind because they were associated with shame or guilt, and that they might account for useless, irrational, or even vicious behavior.
Breuer set out to employ hypnosis to probe the hidden causes of hysteria and other behavior disorders. Working with him was a pupil named Sigmund Freud. For a number of years, they treated patients together, putting the patients under light hypnosis and encouraging them to speak. They found that the patients’ venting of experiences or impulses buried in the unconscious often acted as a cathartic, relieving their symptoms after they awoke from the hypnosis.
Freud came to the conclusion that practically all of the suppressed memories and motivations were sexual in origin. Sexual impulses tabooed by society and the child’s parents were driven underground, but still strove for expression and generated intense conflicts which were the more damaging for being unrecognized and unadmitted.
In 1894, after breaking with Breuer because the latter disagreed with his concentration on the sexual factor, Freud went on alone to develop his ideas about the causes and treatment of mental disturbances. He dropped hypnosis and urged his patients to babble in a virtually random manner—to say anything that came into their minds. As the patient came to feel that the physician was listening sympathetically without any moral censure, slowly—sometimes very slowly—the individual began to unburden himself, to remember things long repressed and forgotten. Freud called this slow analysis of the psyche (Greek for “soul” or “mind”) psychoanalysis.
Freud’s involvement with the sexual symbolism of dreams and his description of infantile wishes to substitute for the parent of the same sex in the marital bed (the Oedipus complex in the case of boys, and the Electra complex in girls—named for characters in Greek mythology) horrified some and fascinated others. In the 1920s, after the dislocations of the First World War and amid the further dislocations of Prohibition in America and changing mores in many parts of the world, Freud’s views struck a sympathetic note, and psychoanalysis attained the status almost of a popular fad.
Nearly a century after its beginnings, however, psychoanalysis still remains an art rather than a science. Rigorously controlled experiments, such as those conducted in physics and the other “hard” sciences, are, of course, exceedingly difficult in psychiatry. The practitioners must base their conclusions largely on intuition or subjective judgment. Psychiatry (of which psychoanalysis is only one of the techniques) has undoubtedly helped many patients, but it has produced no spectacular cures and has not notably reduced the incidence of mental disease. Nor has it developed any all-embracing and generally accepted theory, comparable to the germ theory of infectious disease. In fact, there are almost as many schools of psychiatry as there are psychiatrists.
Serious mental illness takes various forms, ranging from chronic depression to a complete withdrawal from reality into a world in which some, at least, of the details do not correspond to the way most of us see things. This form of psychosis is usually called schizophrenia, a term introduced by the Swiss psychiatrist Eugen Bleuler. The word covers such a multitude of disorders that it can no longer be described as a specific disease. About 60 percent of all the chronic patients in our mental hospitals are diagnosed as schizophrenics.
Until recently, drastic treatments, such as prefrontal lobotomy, or shock therapy using electricity or insulin (the latter technique introduced in 19B by the Austrian psychiatrist Manfred Sakel), were all that could be offered. Psychiatry and psychoanalysis have been of little avail, except occasionally in the early stages when a physician is still able to communicate with the patient. But some recent discoveries concerning drugs and the chemistry of the brain (neurochemistry) have introduced an encouraging note.
Even the ancients knew that certain plant juices could induce hallucinations (fantasies of vision, hearing, and so on) and others could bring on happy states. The Delphic priestesses of ancient Greece chewed some plant before they pronounced their cryptic oracles. Indian tribes of the southwestern United States have made a religious ritual of chewing peyote or mescal buttons (which produce hallucinations in color). Perhaps the most dramatic case was that of the Moslem sect in a mountain stronghold in Iran who used hashish, the juice of hemp leaves, more familiarly known to us as marijuana. The drug, taken in their religious ceremonies, gave the communicants the illusion that they caught glimpses of the paradise to which their souls would go after death, and they would obey any command of their leader, called the Old Man of the Mountains, to receive this key to heaven. His commands took the form of ordering them to kill enemy rulers and hostile Moslem government officials, and thus gave rise to the word assassin, from hashishin (“a user of hashish”). The sect terrorized the region throughout the twelfth century, until the Mongol invaders in 1226 swarmed into the mountains and killed every last assassin.
The modern counterpart of the euphoric herbs of earlier times (aside from alcohol) is the group of drugs known as the tranquilizers. As a matter of fact, one of the tranquilizers had been known in India as long ago as 1000 B.C. in th
e form of a plant called Rauwolfia serpentinum. It was from the dried roots of this plant that American chemists in 1952 extracted reserpine, the first of the currently popular tranquilizing drugs. Several substances with similar effects but simpler chemical structure have since been synthesized.
The tranquilizers are sedatives, but with a difference: they reduce anxiety without appreciably depressing other mental activity. Nevertheless, they do tend to make people sleepy, and they may have other undesirable effects. They were at once found to be immensely helpful in relieving and quieting mental patients, including some schizophrenics. The tranquilizers are not cures for any mental illness, but they suppress certain symptoms that stand in the way of adequate treatment. By reducing the hostilities and rages of patients, and by quieting their fears and anxieties, they reduce the necessity for drastic physical restraints, make it easier for psychiatrists to establish contacts with patients, and increase a patient’s chances of release from the hospital.
But where the tranquilizers had their runaway boom was among the public at large, which apparently seized upon them as a panacea to banish all cares.
DRUG USE
Reserpine turns out to have a tantalizing resemblance to an important substance in the brain. A portion of its complex molecule is rather similar to the substance called serotonin. Serotonin was discovered in the blood in 1948, and it has greatly intrigued physiologists ever since. It was found to be present in the hypothalamus region of the human brain and proved to be widespread in the brain and nerve tissues of other animals, including invertebrates.
What is more, various other substances that affect the central nervous system have turned out to resemble serotonin closely. One of them is a compound in toad venom called bufotenin. Another is mescaline, the active drug in mescal buttons. Most dramatic of all is a substance named lysergic acid diethylamide (popularly known as LSD). In 1943, a Swiss chemist named Albert Hofmann happened to absorb some of this compound in the laboratory and was overcome by strange sensations. Indeed, what he seemed to perceive by way of his senses in no way matched what we would take to be the objective reality of the environment. He suffered what we call hallucinations, and LSD is an example of what we now call a hallucinogen.
