Principal Proposed Uses
Some functions in the body occur automatically, outside of conscious control (such as heart rate and blood pressure). Biofeedback is a method of making those “involuntary” processes something you can do at will.
The basic method is quite simple. In biofeedback, a machine gives you direct information regarding the bodily process in question (the “feedback” part of the term “biofeedback”). Given this information, you can find a way to control it, just like you can learn to wiggle your ears if you try hard enough.
For example, your blood pressure might be displayed on a screen. Blood pressure naturally goes up and down from time to time. When it goes down, you’ll notice that and feel pleased; when it goes up, you’ll feel displeased. Pleasure and displeasure act like the reward and punishment technique used for training animals. When a rat in a maze is rewarded with food for going the right way and given an electric shock for going the wrong way, it will soon learn to go the right way. Similarly, the unconscious parts of the nervous system figure out a way to get a "reward" instead of receive "punishment." In the case just described, this means reducing blood pressure.
The display screen provides the feedback because normally we can’t detect our own blood pressure. Using a machine to provide that information allows the person to achieve conscious control. This process generally works, at least to a modest extent. After a number of sessions, most people reach a place where they can lower their blood pressure simply by thinking, “I want my blood pressure to fall.” They don’t know how they're doing it (any more than ear wigglers know how they’ve accomplished that); nonetheless, they can cause the desired effect.
In addition to measuring blood pressure and heart rate, there are biofeedback machines in fairly common use that measure muscle tension, skin temperature, skin resistance to electricity, and brain wave activity.
What Is Biofeedback Used For?
Probably the most common use of biofeedback is to treat stress and stress-related conditions, including anxiety , insomnia , high blood pressure , fibromyalgia , muscle pain, migraine headaches , and tension headaches .
What Is the Scientific Evidence for Biofeedback?
However, it is somewhat tricky to fit biofeedback into a study design of this type. The main problem is finding a placebo for biofeedback treatment. In the best-designed studies of biofeedback, people in the placebo group practice biofeedback with a machine that produces carefully garbled information. Study participants in this group believe they are practicing biofeedback, but in fact they are not learning any conscious control over the body process in question.
Many biofeedback studies do not use placebo biofeedback; they compare biofeedback to no treatment. Studies of this type cannot provide reliable evidence about the efficacy of a treatment. If a benefit is seen, there is no way to determine whether biofeedback caused it or whether it was caused generically by attention. (Attention alone will almost always produce some reported benefit.)
Other trials used intentionally neutral therapies, such as the use of a home diary. These are better than studies with a no-treatment control group. However, when the placebo is so different in form than the treatment under study, any apparent differences in outcome could simply represent differences in the power of suggestion in each approach.
Given these caveats, the following is a summary of what science knows about the medical benefits of biofeedback.
What to Expect During a Biofeedback Session
As described above, biofeedback training involves the use of a machine that relays information about the aspect of the body that you wish to control. In early stages, the trick is finding the “muscles” necessary to produce the desired effect. Typically, a biofeedback practitioner will teach a series of visualizations and other mental exercises in the hope that it will facilitate the process. For example, if you have high blood pressure, you might be asked to imagine the blood vessels in your body opening up and dilating.
How to Choose a Biofeedback Practitioner
As with all medical therapies, it is best to choose a licensed practitioner in states where a biofeedback license is available. Where licensure is not available, seek a referral from a qualified and knowledgeable healthcare provider.
- Reviewer: EBSCO CAM Review Board
- Review Date: 07/2012 -
- Update Date: 07/25/2012 -