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CHAPTER THREE

The Birth of Biofeedback

In 1958 a graduate student named Richard Bach made history as the first person to control his brain waves, as part of an experiment designed by a psychologist named Joe Kamiya, who taught at the University of Chicago. Kamiya had gone to college during the heyday of behaviorism, yet he thought there was something wrong with viewing humans as nothing more than an accumulation of their genetics and their response to external stimuli. What about dreams and introspection? He remembered being deeply concerned as a young man with existential questions about the universe and his place in it. Behaviorists considered such thoughts irrelevant, nothing more than noise in the system.

The Japanese-American psychologist disagreed and wondered what verbal description people would give different states indicated by their brain waves. Could an EEG show when someone was introspective? The first order of business would be to condition people to produce certain frequencies so they could be studied. For the first experiment Kamiya chose alpha, in the 8-to-12-hertz range, which is the most prominent rhythm in the brain and easy to produce, and might, Kamiya felt, lie within the frequency range of introspection.

He designed a controlled experiment to find out if someone could distinguish between the different brain wave categories. It wouldn't be easy, for there is only a subtle difference between brain waves. Kamiya attached a sensing electrode to the left side of the back of Bach's head—the left occiput, which is where alpha is most evident. As the student lay in a darkened chamber, Kamiya watched his EEG and spoke to him by intercom. “Keep your eyes closed,” Kamiya told him. “I am going to sound a series of tones.” After each tone sounded, the subject was to guess whether he was in alpha. Kamiya knew from the EEG if it was alpha, but the subject did not. When he said “yes” or “no,” Kamiya would answer, “Correct” or “Wrong,” depending on whether he was in alpha or not. “He asked me how he should go about it,” Kamiya says. “I said, ‘I don't know,’ but I asked him to pay attention to what state of mind he was in when the guesses were right and when the guesses were wrong.”

On the first day of trials—which consisted of sixty tones and sixty guesses in a thirty-minute session—Bach got about half of his guesses correct, about the same that could be accomplished by flipping a coin. The second day he got 65 percent correct, “which still is not much to write home about,” says Kamiya. “But on the third day he got eighty-five percent correct, and now it's getting kind of interesting.” On the fourth day, the subject made a couple of mistakes at the outset and from then on got all the rest correct. Intrigued, Kamiya decided to keep going and kept sounding the tone. Before it was over, he had sounded the tone four hundred times and gotten a correct answer each time. It went on so long Bach began to think there was something fishy and deliberately gave a wrong answer. For the first time in several hundred trials Kamiya answered, “Wrong.” To this day, Kamiya remains in awe of Bach's ability to identify alpha. “I like to say that the first subject I had was sent by God, because I never had another subject who became as accurate in guessing their brain state as this guy was. The result was so unambiguous that it encouraged me to keep going. If I had kept getting fifty percent and I had to run a thousand sessions to find this kind of success, I might not have continued.”

In the second part of the study, the student was asked to enter into the alpha state when a bell was rung once and not go into the state when it was rung twice. Again, Bach was masterful. “He had perfect control,” Kamiya says. The subject and some others were also adept in learning to vary their alpha, going from low alpha to high alpha and back as they wished. “They were able to enter and sustain either state upon our command,” Kamiya says. Others could not control it at all. It was the first controlled experiment to demonstrate that brain waves, normally thought of as involuntary, were subject to voluntary control. It launched the field of brain wave biofeedback.

Kamiya asked his prize pupil how he did it, but the young man said he wasn't sure. After more trials, however, he told the researcher that he found himself in the alpha state when visual images were absent from his mind. “When I imagine music from an orchestra, I'm in alpha,” he said, “but when I imagine a visual image of the orchestra, it seems to cause an absence of alpha.” Others described alpha as “letting the mind wander,” “feeling the heart beat,” and “not thinking.”

Kamiya didn't see the experiments as significant at the time. “We were just curious to see if people could control their brain rhythms,” he says. “We had no intention to help the ailments of mankind.” Kamiya's work did not become well known until an article about it was published in Psychology Today in 1968, after he had moved to the Langley Porter Neuropsychiatric Institute in San Francisco.

As a general concept, biofeedback has been around a long time. It's a way of gaining information about the body to better manage it. Looking at a reflection in a mirror to comb your hair or put on lipstick is getting a very basic kind of feedback. Using a thermometer to take your temperature and to help you decide whether to take an aspirin is a kind of biofeedback. The first known record of biofeedback, or “self-regulation,” with instrumentation to control part of the body not normally under voluntary control was in 1901. A man named J. H. Bair wrote a report called “Development of Voluntary Control” in which he described a mechanical device he had invented that allowed people to gain control of the muscles that wiggle the ears. He designed it, he said, “because of the light its solution would throw upon the nature of the will.” The first brain wave biofeedback was reported in 1934 by E. D. Adrian at Cambridge, who with his partner, B.H.C. Matthews, had replicated Hans Berger's work, as mentioned in chapter 2. Sitting in front of an oscillograph and an amplifier that played a beat that reflected the frequency of his EEG, Adrian found that he could create the alpha rhythm at will “as soon as the eyes are closed, and maintain it with rare and brief intermissions as long as they remained closed.”

The field of modern biofeedback that was born in the 1950s and 1960s was the outgrowth of two developments. First was the burst of evolution of electrical instrumentation that grew out of the war effort during World War II. Equipment up until that time wasn't sensitive enough to measure the body's faint electrical impulses very accurately. Second was research on stress and the role it played in illness. Walter B. Cannon was one of the first physiologists to study the powerful and long-lasting effects of stress on the human body in the early part of the twentieth century. (Stress comes from the Latin word strictus, which means tight and narrow.) In his lab at the Harvard Medical School, Cannon fed a cat food that was laced with a radioactive element called barium, so he could observe the cat's stomach with an x-ray. As long as the cat was content, its stomach muscles digested the meal in wavelike motions. When Cannon provoked the animal to anger or frustration, however, the stomach immediately halted its digestive motions and froze, even if the stimulus was removed, for an hour or more. The cat's body stopped nonessential activity to prepare to defend itself or to escape; Cannon dubbed the response “fight or flight.”

Cannon also studied the profound effects the hormone adrenaline has on the human body. Just a couple of drops dissolved in 100,000 parts of water and injected into the cat caused it to arch its back, bare its claws, and dilate its eyes. Heart rate and breath rate, the amount of sugar in the blood, and blood pressure all increased. Cannon collected urine from members of the Harvard football team during an exciting game and found the same thing: a detectable increase in adrenaline and in sugar. Subsequent studies have shown that even being asked to solve a complicated math problem can evoke a milder version of the fight-or-flight response.

Another pioneer in stress research was Hans Selye, a researcher at McGill University in Montreal. In the 1950s Selye wrote a best-selling book called The Stress of Life and introduced what he called general adaptation syndrome (GAS). There are two components to the autonomic nervous system—the parasympathetic, which dominates during relaxation, and the sympathetic, which is switched on in reaction to external stress. Humans, Selye said, suffer from chronic activation of the sympathetic nervous system.

The first part of GAS is called the alarm stage. In response to a perceived threat—a car swerving toward you, a stranger walking quickly up behind you on a dark, lonely street—your body prepares itself to fight or take flight. Stress chemicals flood the body, making the heart beat faster, constricting blood vessels in the limbs to keep blood in the trunk, increasing breathing and perspiration, tensing muscles. When the situation calms, you go on about your business. The problem is that the body and mind often do not completely return to their original state; they've been permanently changed by the event. Capillaries throughout the body have constricted, heart muscles stressed, and muscles have retained some tension. This is viewed as remnant behavior, a holdover from the days when humans in a wild environment needed a surge of energy to deal with an attack by an animal or an enemy tribe.

The second part of GAS is called adaptation. After a while, a person gets used to the stress, even though the body and mind have not returned to their original state. If coping is not successful, the stress continues to exact a toll, to cause problems in the body, even though the person is unaware of it. That sets up Selye's final stage: exhaustion. The list of symptoms that may be related to stress-induced exhaustion is a long, seemingly all-encompassing one: anxiety, a variety of pains, depression, headaches, stomach and bowel problems, asthma, coldness in the extremities. Heart disease has long been associated with stress, especially in about 20 percent of the population known as “hot reactors.” During the stress of daily events, the blood pressure of such people can shoot from a normal resting level of 120 to a whopping 300 and can eventually lead to a heart attack or stroke.

Stress can also dramatically impact immune system function. Robert Ader, a researcher at the University of Rochester School of Medicine and Dentistry, was one of the first to demonstrate that when he conducted a study of conditioned taste aversion on lab animals. The question was, Could a lab animal be taught not to like a favorite food? The answer was yes. Ader found that if he fed an animal sugar water, which it loved, and then fed it a nausea-inducing substance, the animal would no longer drink sugar water. But the really interesting discovery was accidental. By chance, Ader used an immunosuppressant—a drug that is used in transplant patients to keep their immune system from attacking their new organ—to cause the nausea. He later found that animals that had been conditioned to pair the taste of sugar water with immunosuppression had a much higher mortality rate when they drank sweetened water alone. The animals had been conditioned to diminish the function of their immune systems, which demonstrated a direct psychological effect on immunity.

What's been added to the body of knowledge about stress in recent years is the profound impact that emotions have on the nervous system. “The prime directive of the brain,” writes Dr. Bruce Perry, a trauma specialist, “is to promote survival and procreation. The brain is ‘over determined’ to sense, process, store, perceive, and mobilize in response to threatening information from the external and internal environments. All areas of the brain and body are recruited and orchestrated for optimal survival tasks during the threat. This total neurobiological participation is important in understanding how a traumatic experience can impact and alter functioning in such a pervasive fashion. Cognitive, emotional, social, behavioral and physiological residue of a trauma may impact an individual for years—even a lifetime.”

A stress chemical called Cortisol is emerging as a primary player in damage to the brain. “It is the master stress hormone,” said Dr. Ned Kalin, a psychiatrist at the HealthEmotions Research Institute at the University of Wisconsin, where they are studying the effects of stress on the brain with state-of-the-art brain imaging and molecular techniques. “In low doses it alerts us and organizes our behavior so we make sure to protect ourselves.” But in higher doses, he said, “it leaves us stressed out, inattentive, disorganized and depressed. Severe stress affects the size of the structure [in the brain], cell death, and the number of connections between brain cells. And earlier in life the brain is much more vulnerable to insult.” Topping the list of stressors, as numerous studies attest, is an absence of solid, caring relationships. “A car wreck is bad,” in terms of stress, said Kalin, “But its not as bad as being neglected, isolated, or ostracized by your peers. Deprivation—lack of love, comfort security—is very stressful and can have big time effects.” A study at the University of Minnesota showed that children who have a poor emotional attachment to their parents get higher rushes of Cortisol during even mildly painful events, such as being vaccinated, than do children with strong parental bonds.

Research has shown that sustained exposure to Cortisol can cause serious damage to the hippocampus, which affects memory, mood regulation and interpretation of space. Some researchers believe Cortisol may also cause damage to other parts of the brain, notably the left prefrontal cortex. This region of the brain, right behind the forehead, is vital to humans, orchestrating emotion, arousal and attention and providing a restraint mechanism that keeps people from acting on impulse. It is key in teaching a child to feel remorse and establish a conscience. In fact, the prefrontal cortex is known as the “Organ of Civilization” because it is largely what distinguishes us from animals.

According to work at the University of Wisconsin and elsewhere the left prefrontal cortex plays a key role in integrating positive emotion into people's lives. The tiny bit of tissue drives the networks in the brain that makes us feel good, while the right side drives anger, fear and other negative emotions. When the frequency of the two sides isn't balanced and the right side is higher than the left, people can't engage their positive emotions and become depressed.

Some research has shown stress has an extremely deleterious effect on the prefrontal cortex. Bruce Perry, a researcher at the Baylor College of Medicine has done brain scans of children who have been severely neglected. Key portions of their brain, he says, don't develop properly and are nearly a third smaller than the brain of a normal child of similar age. And with key areas of the brain damaged, problems arise. Adrian Raine, a psychologist at the University of Southern California, did a study in 1999 of twenty-one men with psychopathic personalities who had committed violent crimes. All of them had 11 to 14 percent fewer nerve cells in the prefrontal cortex—about two teaspoon's worth.

If key parts of the brain, or the entire brain, are weakened by stress chemicals, it could have major effects on the body as well. A common denominator in everything from chronic pain to immune dysfunction to heart disease and depression may be in the brain. “Many of these systems are regulated by the brain,” said Kalin. “Hormones are regulated through the central nervous system for example and the brain, through the peripheral nervous system regulates pain responses, heart rate, a whole bunch of things.” It seems that when stress damages the brain, it is analogous to damaged lines of code in computer software—neither body nor mind will operate correctly until the damage is fixed.

Where does stress come from? Some of the first exposures are the fearful or anxious experiences children have. An infant that cries unanswered, for example. Children who are yelled at or nearly hit by a car or forget to bring their homework to school or are physically abused or feel unloved all suffer varying degrees of psychological and physiological stress. It doesn't matter whether the threat is real or imaginary; the physiological response is the same.

Stress continues throughout life. Researchers Raymond Cochrane and Alex Robertson have compiled a Life Events Inventory and numerically ranked the stressful events that people experience, with such things as unemployment and a prison sentence at the top of the list, while going on vacation and getting new neighbors are near the bottom. There are also background stressors, those that are chronic and repetitive: traffic, noise, hectic schedules, family and job problems.

Biofeedback researchers have, over the years, developed a set of tools that measure stresses in different parts of the body and teach the client to reverse them by training various parts of the body to relax, many of which were thought for a long time to be beyond conscious control. In the 1960s in a book called Muscles Alive, John Basmajian, a researcher at Harvard, described an experiment he had conducted. He was studying cells in the brain's motor cortex, which send the message to muscle cells in the body to fire. An organized nerve path in the motor cortex is called a motor unit, and a single motor unit that travels down the spine might control anywhere from a few muscle cells to hundreds of them. Basmajian chose a motor unit that controlled a few cells at the base of the thumb. He inserted a tiny needle electrode into the thumb muscle. No one could see any movement of the muscle, but half of Basmajian's sixteen subjects were able to control the firing of a single motor unit in the brain that governed that muscle. The electrical impulse sent by the motor unit to the thumb was picked up and amplified over a loudspeaker. Each time a subject fired the small cluster of nerve cells, a click sounded over the speaker. The subjects learned to play distinctive tattoos by firing the brain cells once, twice, three times. They could imitate the sound of galloping horses and drum rolls on command. It was a finding far ahead of its time—the subjects had easily learned to handily control a tiny group of cells by use of their will. Basmajian asked them to describe how they did it. They couldn't, they said—they just did it.

Basmajian and a few other scientists went on to create the primary tool for traditional biofeedback, the electromyograph (EMG). People tend to hold chronic tension in certain muscles. Since tense muscles have a higher electrical reading than relaxed ones, small sensing electrodes are attached to tense muscles. The frontalis, the forehead muscle, for example, is a primary target for EMG, because when people concentrate hard or worry or suffer emotional distress, this is one of the muscles they often tense. The equipment displays the measurement on a computer screen and tells clients which of their efforts to relax the muscle are successful. EMG is used primarily for headaches and stress. Pelvic muscles are also trained with EMG to combat incontinence.

Hand warming is another long-time biofeedback task. A thermometer is attached to a finger; when the client successfully relaxes, the temperature on a digital readout rises or a tone beeps more slowly. Below-normal temperatures usually occur in people with anxiety, migraines, menstrual problems, and stomach disorders, and once a person learns to warm his or her hands, many of the other problems are alleviated or lessened. Another common type of feedback is galvanic skin response, or GSR. Stress causes increased perspiration, which is salty and a conductor of electricity. A fingertip sensor is placed on the hand, and as the client lowers his or her stress level, a beeping sound decreases. There are several other kinds of biofeedback, which measure heart rate, respiration, and other indicators.

Despite solid scientific credentials, biofeedback is an ungainly stepchild in the medical world, primarily because the biofeedback model is very different from that of allopathic medicine. When health problems arise, most people are accustomed to having something done to them: they are given a pill, subjected to an x-ray or an MRI, have their gall bladder taken out, or have new arteries made for their heart. Biofeedback requires the patient to take some responsibility for his or her own health; it is about learning how the body and mind work and making changes based on that learning. It takes time and patience and a certain level of commitment.

Brain wave biofeedback, or neurofeedback, is a different creature from standard relaxation training. Because the brain governs the whole body, brain wave training is considered much more global than other modalities that operate further “downstream.” Neurofeedback is different than other kinds of biofeedback in another sense. Muscle biofeedback, or EMG, for example, requires a fair amount of conscious effort. A client must be aware of his or her clenched jaw muscles during the session, but also afterward. EMG clients must consciously work at letting go of tension after they leave the therapist's office and often wear a blue dot on their hand so they remember to change their habitual tension and relax certain muscles or muscle groups. Brain wave training is much more automatic. A person does a forty-five minute session. After they leave, it's over. Nothing to be mindful of, no blue dots. Even though a client is changing his or her own brain, the training is so powerful and simple that it is very different from other kinds of biofeedback.

After Joe Kamiya's work with Richard Bach, early reports by neurofeedback proponents indicated that alpha training might be a panacea that would reduce all of the body's accumulated stress all at once, a healing system that would normalize all body function. By reducing stress in the brain, which controls everything else, muscle tone, hand temperature, and skin conductivity would be brought to a healthy, comfortable state. And it would alleviate stress in the tissue of the brain as well. Brain wave training would clear the body and the mind.

Kamiya's work generated a great deal of excitement in the psychological community. One evening, he mentioned his work to Abraham Maslow, the founder of the humanistic school of psychology, and the next morning at six A.M. Maslow called him and said brain wave training implied an undreamt-of level of control that was so exciting he had been unable to sleep. Other researchers heard of Kamiya's work and started research of their own. Psychology Today did a piece on Kamiya in 1968, and things really took off. Some people who came out of the alpha state reported feeling rested and sharp, as if they had awakened from a nap with a clear head, while others reported overwhelming feelings of tranquillity and reverie. Some of Kamiya's subjects clamored for more training, so they could experience alpha again. Some artists and musicians reported experiencing intense rushes of creativity, and others described sensations of floating. Yet some people reported nothing. “We found that people who were relaxed, comfortable, and cooperative tended to produce more alpha waves than those who felt tense, suspicious, and fearful or who actively thought of what was going to happen next,” Kamiya says. He also says that he believes the production of alpha depended a great deal on whether there was a rapport between the researcher and the subject. “It's a key factor,” he says.