An Introduction to Neurofeedback

By D. Corydon Hammond, PhD, ABEN, QEEG-D, Univ. of Utah School of Medicine

In the late 1960's and 1970's we learned that it was possible to recondition and retrain brainwave patterns. Some of this work began with the training of alpha brainwave activity for relaxation, while other work originating at UCLA focused on uncontrolled epilepsy. This training is called EEG biofeedback or neurofeedback. Before discussing this in more detail, let me provide you with some preliminary information about brainwaves. Brainwaves occur at various frequencies. Some are fast and some are quite slow. The classic names of these EEG bands are delta, theta, alpha, and beta. They are measured in cycles per second or hertz (Hz).

Beta brainwaves are small, faster brainwaves (above 13 Hz) associated with a state of mental, intellectual activity and outwardly focused concentration. This is basically a “bright-eyed, bushy-tailed” state of alertness. Alpha brainwaves (8-12 Hz.) are slower and larger. They are associated with a state of relaxation and basically represent the brain shifting into an idling gear, relaxed and a bit disengaged, waiting to respond when needed. If we merely close our eyes and begin picturing something peaceful, in less than half a minute there begins to be an increase in alpha brainwaves. These brainwaves are especially large in the back third of the head. Theta (4-8 Hz) brainwaves represent a day dreamy, spacey state of mind that is associated with mental inefficiency. At very slow levels, theta brainwave activity is a very relaxed state, representing the twilight zone between waking and sleep. Delta brainwaves (0-3.5 Hz) are the slowest, highest amplitude brainwaves, and are what we experience when we are asleep. In general, different levels of awareness are associated with dominant brainwave states.

Each of us, however, always has some degree of each of these brainwave bands present in different parts of our brain. Delta brainwaves will also occur, for instance, when areas of the brain go “off line” to take up nourishment. If we are becoming drowsy, there are more delta and slow theta brainwaves creeping in, and if we are inattentive to external things and our mind is wandering, there is more theta present. If we are exceptionally anxious and tense, an excessively high frequency of beta brainwaves is often present. Persons with ADD, ADHD, learning disabilities, head injuries, stroke, Tourette’s syndrome, epilepsy, and often chronic fatigue syndrome and fibromyalgia tend to have excessive slow waves (usually theta and sometimes excess alpha) present. When an excessive amount of slow waves are present in the executive (frontal) parts of the brain, it becomes difficult to control attention, behavior, and/or emotions. Such persons generally have problems with concentration, memory, controlling their impulses and moods, or with hyperactivity. They can’t focus very well and exhibit diminished intellectual efficiency.

What is Neurofeedback Training?

Neurofeedback training is brainwave biofeedback. During typical training, a couple of electrodes are placed on the scalp and one or two are usually put on the ear lobe. Then, high-tech electronic equipment provides you with real-time, instantaneous audio and visual feedback about your brainwave activity. The electrodes measure the electrical patterns coming from the brain--much like a physician listens to your heart from the surface of your skin. No electrical current is put into your brain. Your brainwave patterns are relayed to the computer and recorded.

Ordinarily, we cannot influence our brainwave patterns because we lack awareness of them. However, when you can see your brainwaves on a computer screen a few thousandths of a second after they occur, it gives you the ability to influence and change them. The mechanism of action is operant conditioning. We are literally reconditioning and retraining the brain. At first, the changes are short-lived, but the changes gradually become more enduring. With continuing feedback, coaching, and practice, we can usually retrain healthier brainwave patterns in most people. It is a little like exercising or doing physical therapy with the brain, enhancing cognitive flexibility and control. Thus, whether the problem stems from ADD/ADHD, a learning disability, a stroke, head injury, deficits following neurosurgery, uncontrolled epilepsy, cognitive dysfunction associated with aging, depression, anxiety, obsessive-compulsive disorder, or other brain-related conditions, neurofeedback training offers additional opportunities for rehabilitation through directly retraining the brain. The exciting thing is that even when a problem is biological in nature, we now have another treatment alternative than just medication. Neurofeedback is also being used increasingly to facilitate peak performance in “normal” individuals and athletes.

Frank H. Duffy, M.D., a Professor and Pediatric Neurologist at Harvard Medical School, stated in an editorial in the January 2000 issue of the journal Clinical Electroencephalography that scholarly literature now suggests that neurofeedback “should play a major therapeutic role in many difficult areas. In my opinion, if any medication had demonstrated such a wide spectrum of efficacy it would be universally accepted and widely used” (p. v). “It is a field to be taken seriously by all” (p. vii).

Assessment Prior to Neurofeedback Training

Prior to doing neurofeedback training, clinicians usually want to ask questions about the symptom history of the patient. In some cases they may do neuropsychological or psychological testing. Competent clinicians will also examine brainwave patterns. Some practitioners may do this by placing one or two electrodes on the scalp and measuring brainwave patterns in a few limited areas. Other clinicians perform more comprehensive testing called a quantitative electroencephalogram (QEEG) or brain map where . . . electrodes are placed on the scalp.

A QEEG is an assessment tool to objectively and scientifically evaluate a person’s brainwave function. . . . This is done while the patient is resting quietly with his or her eyes closed, and sometimes also with eyes open or during a task such as reading. Afterwards, we then go through a tedious and lengthy procedure to remove any artifacts that occurred when the eyes moved or blinked, when patients moved slightly in the chair, or tightened their jaw or forehead a little bit. The brainwave data we gathered is then compared to a sophisticated normative database of how the brain should be functioning . . .This assessment procedure allows us to then determine in a highly scientific, objective manner whether and how a patient’s brainwave patterns are significantly different from normal.

Beginning during the 1970's and 1980's there began to be a great deal of experimentation with QEEG. The American Medical EEG Association Ad Hoc Committee on QEEG has stated that QEEG “is of clinical value now and developments suggest it will be of even greater use in the future.” QEEG has scientifically documented ability to aid in the evaluation of conditions such as mild traumatic brain injury, ADD/ADHD, learning disabilities, depression, obsessive-compulsive disorder, anxiety and panic disorder, and a variety of other conditions (including autism, schizophrenia, stroke, epilepsy, and dementia). QEEG has even been able to predict outcomes from treating conditions such as ADD/ADHD, alcoholism, and drug abuse. The American Psychological Association has also endorsed QEEG as being within the scope of practice of psychologists who are appropriately trained, and ISNR has similarly endorsed its use by legitimate health care professionals who are appropriately trained.

The EEG and QEEG evaluations assist us in knowing if there are abnormalities in brain function that EEG neurofeedback might be helpful in treating, and it allows us to know how we can individualize neurofeedback to the unique problems of each patient. For example, scientific research has identified a minimum of three major subtypes of ADD/ADHD, none of which can be diagnosed from observing the person’s behavior, and each of which requires a different treatment protocol.

For more information about neurofeedback, I recommend the following web sites which I have found to have good educational content.

1. The International Society for Neuronal Regulation:

2. Association for Applied Psychophysiology & Biofeedback: