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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? TOP
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? TOP
Although many studies have evaluated biofeedback, most of them suffer from inadequate design.1 Only one form of study can truly prove that a treatment is effective: the double-blind, placebo-controlled trial. (For more information on why such studies are so crucial, see Why Does This Database Rely on Double-blind Studies?)
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.
Still other studies simply involved giving people biofeedback and seeing whether they improved. Such trials are almost completely meaningless; numerous studies have shown that both participants and examining physicians will frequently think they observe improvement in people given a treatment, regardless of whether the treatment does anything on its own. For example, early studies of biofeedback for stroke rehabilitation that did not use blinding or a control group reported miraculous successes equivalent to the “throw down your crutches and walk” cliché.2 However, when controlled trials were performed, it turned out that biofeedback did not provide much more than marginal benefit, if any. For this reason, we do not even report uncontrolled studies below.
Given these caveats, the following is a summary of what science knows about the medical benefits of biofeedback.
Possible Effects of Biofeedback
Of all the medical conditions for which biofeedback has been advocated, the best studied is hypertension. However, a review of the literature published in 2003, which found 22 controlled trials of acceptable quality,3 concluded that real biofeedback is not more effective than fake biofeedback. A study published subsequent to this review did report benefits, but it was poorly designed.24 In addition, a 2010 review of 36 trials involving 1,660 patients found no consistent evidence that biofeedback's effectiveness for hypertension compared to other behavioral therapies, drug therapy, placebo, or no intervention.31
Prehypertension is a condition where blood pressure is elevated above what is considered normal, but not the level of a hypertension diagnosis. A small randomized trial involving 43 patients with prehypertension showed that heart rate variability feedback reduced systolic blood pressure compared to slow abdominal breathing and control groups.34
Biofeedback has been studied for other medical conditions as well. At least one controlled study supports the use of biofeedback for each of the following: anxiety,12,33 chronic low-back pain,13 female stress incontinence,14 incontinence associated with radical prostatectomy,29insomnia,5 and, possibly, rehabilitation from strokes.18-20 Note that the evidence of benefit with biofeedback is not definitive for any of these conditions, and in many cases there are also studies with negative outcomes.
There is mixed evidence for the effectiveness of biofeedback for recurrent headaches, both migraine and tension.15-17 In a detailed review of multiple controlled studies, however, researchers concluded that biofeedback is useful for tension headaches, particularly when combined with other relaxation therapies.25 And, in another review of 94 studies, researchers concluded that biofeedback is capable of significantly reducing the frequency for both migraine and tension-type headaches, among other benefits.27 However, it is important to note that not all of the studies they used to arrive at this conclusion were randomized, placebo-controlled trials.
The balance of the evidence suggests that biofeedback is not effective for asthma,7 and no more than marginally effective for Raynaud’s disease.10,11 Evidence is mixed regarding biofeedback’s effectiveness for constipation and fecal incontinence.8-9,21,23-24,28,30 However, a number of small trials have found biofeedback to be more effective than standard therapies alone for constipation related to pelvic floor dysfunction.26,32
What to Expect During a Biofeedback Session TOP
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 TOP
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.
Safety Issues TOP
There are no known safety risks with biofeedback.
References[ + ]
1. Yucha CB. Problems inherent in assessing biofeedback efficacy studies. Appl Psychophysiol Biofeedback. 2002;27:99-106.
2. Glanz M, Klawansky S, Chalmers T. Biofeedback therapy in stroke rehabilitation: a review. J R Soc Med. 1997;90:33-39.
3. Yucha CB, Clark L, Smith M, et al. The effect of biofeedback in hypertension. Appl Nurs Res. 2001;14:29-35.
4. Henderson RJ, Hart MG, Lal SK, et al. The effect of home training with direct blood pressure biofeedback of hypertensives: a placebo-controlled study. J Hypertens. 1998;16:771-778.
5. Morin CM, Hauri PJ, Espie CA, et al. Nonpharmacologic treatment of chronic insomnia. Sleep. 1999;22:1134-1156.
6. Henderson RJ, Hart MG, Lal SK, et al. The effect of home training with direct blood pressure biofeedback of hypertensives: a placebo-controlled study. J Hypertens. 1998;16:771-778.
7. Huntley A, White AR, Ernst E. Relaxation therapies for asthma: a systematic review. Thorax. 2002;57:127-131.
8. Coulter ID, Favreau JT, Hardy ML, et al. Biofeedback interventions for gastrointestinal conditions: a systematic review. Altern Ther Health Med. 2002;8:76-83.
9. Loening-Baucke V. Biofeedback training in children with functional constipation. A critical review. Dig Dis Sci. 1996;41:65-71.
10. Raynaud's Treatment Study Investigators. Comparison of sustained-release nifedipine and temperature biofeedback for treatment of primary Raynaud’s phenomenon. Results from a randomized clinical trial with 1-year follow-up. Arch Intern Med. 2000;160:1101-1108.
11. Freedman RR, Ianni P, Wenig P. Behavioral treatment of Raynaud's phenomenon in scleroderma. J Behav Med. 1984;7:343-353.
12. Moore NC. A review of EEG biofeedback treatment of anxiety disorders. Clin Electroencephalogr. 2000;31:1-6.
13. Nielson WR, Weir R. Biopsychosocial approaches to the treatment of chronic pain. Clin J Pain. 2001 Dec;17(4 Suppl):S114-S127.
14. Weatherall M. Biofeedback or pelvic floor muscle exercises for female genuine stress incontinence: a meta-analysis of trials identified in a systematic review. BJU Int. 1999;83:1015-1016.
15. Lake AE 3rd. Behavioral and nonpharmacologic treatments of headache. Med Clin North Am. 2001;85:1055-1075.
16. Duckro PN, Cantwell-Simmons E. A review of studies evaluating biofeedback and relaxation training in the management of pediatric headache. Headache. 1989;29:428-433.
17. Hermann C, Blanchard EB. Biofeedback in the treatment of headache and other childhood pain. Appl Psychophysiol Biofeedback. 2002;27:143-162.
18. Wolf SL. Electromyographic biofeedback applications to stroke patients. A critical review. Phys Ther. 1983;63:1448-1459.
19. de Pedro-Cuesta J, Widen-Holmqvist L, Bach-y-Rita P. Evaluation of stroke rehabilitation by randomized controlled studies: a review. Acta Neurol Scand. 1992;86:433-439.
20. Glanz M, Klawansky S, Chalmers T. Biofeedback therapy in stroke rehabilitation: a review. J R Soc Med. 1997;90:33-39.
21. Chiarioni G, Ferri B, Morelli A, et al. Bio-feedback treatment of fecal incontinence: Where are we, and where are we going? World J Gastroenterol. 2005;11:4771-4775.
22. Rao SS, Seaton K, Miller M, et al. Randomized controlled trial of biofeedback, sham feedback, and standard therapy for dyssynergic defecation. Clin Gastroenterol Hepatol. 2007;5:331-338.
23. Heymen S, Wexner SD, Vickers D, et al. Prospective, randomized trial comparing four biofeedback techniques for patients with constipation. Dis Colon Rectum. 1999;42:1388-1393.
24. Tsai PS, Chang NC, Chang WY, et al. Blood pressure biofeedback exerts intermediate-term effects on blood pressure and pressure reactivity in individuals with mild hypertension: a randomized controlled study. J Altern Complement Med. 2007;13:5:547-554.
25. Nestoriuc Y, Rief W, Martin A. Meta-analysis of biofeedback for tension-type headache: Efficacy, specificity, and treatment moderators. J Consult Clin Psychol. 2008;76:379-396.
26. Koh CE, Young CJ, Young JM, et al. Systematic review of randomized controlled trials of the effectiveness of biofeedback for pelvic floor dysfunction. Br J Surg. 2008 Jul 25.
27. Nestoriuc Y, Martin A, Rief W, et al. Biofeedback treatment for headache disorders: a comprehensive efficacy review. Appl Psychophysiol Biofeedback. 2008 Aug 26.
28. Coulter ID, Favreau JT, Hardy ML, Morton SC, Roth EA, Shekelle P. Biofeedback interventions for gastrointestinal conditions: a systematic review. Altern Ther Health Med. 2002;8:76-83.
29. Mariotti G, Sciarra A, Gentilucci A, et al. Early recovery of urinary continence after radical prostatectomy using early pelvic floor electrical stimulation and biofeedback associated treatment. J Urol. 2009;181:1788-93.
30. Heymen S, Scarlett Y, Jones K, et al. Randomized controlled trial shows biofeedback to be superior to pelvic floor exercises for fecal incontinence. Dis Colon Rectum. 2009;52:1730-7.
31. Greenhalgh J, Dickson R, Dundar Y. Biofeedback for hypertension: a systematic review. J Hypertens. 2010 Jan 19 early online.
32. Rao SS, Valestin J, Brown CK, et al. Long-term efficacy of biofeedback therapy for dyssynergic defecation: randomized controlled trial. Am J Gastroenterol. 2010 Apr;105(4):890
33. Lande RG, Williams LB, Francis JL, Gragnani C, Morin ML. Efficacy of biofeedback for post-traumatic stress disorder. Complement Ther Med. 2010;18(6):256-259.
34. Lin G, Xiang Q, Fu X. Heart rate variability biofeedback decreases blood pressure in prehypertensive subjects by improving autonomic function and baroreflex. J Altern Complement Med. 2012;18(2):143-152.
Last reviewed September 2014 by EBSCO CAM Review Board
Last Updated: 9/18/2014
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