Since Miller's experiments with rats, biofeedback-feeding back information on body functioning to allow a person to learn how to actively control these functions-has become an accepted form of therapy, with a number of different machines designed to meas-ure a range of physical responses.
The conditions that respond best to biofeedback are generally stress-related, including headaches, insom-nia, asthma, gastrointestinal disorders and mild hypertension. However, as the research continues, more and more uses are being discovered.
Electromyography (EMG) biofeed-back-which measures the electrical output of muscles-has helped fibro-myalgia, characterized by widespread musculoskeletal pain and tenderness. Six days of EMG biofeedback treat-ment decreased the number of tender points as well as improved patients' general physical and psychological status (Indian J Med Sci, 2007; 61: 455-61).
Such improvements were still present two months after the end of EMG treatment. Patients also experi-enced significant improvements in other disease symptoms, including sleep problems and headache (Wien Med Wochenschr, 1999; 149: 561-3).
In 30 patients with type 2 (non-insulin-dependent) diabetes, 10 sessions of biofeedback and relaxation signifi-cantly lowered blood glucose levels. These effects lasted for up to three months after treatment (Diabetes Care, 2005; 28: 2145-9). Similar results have also been seen in type 1 diabetes (Diabetes Care, 1991; 14: 360-5).
Electroencephalography (EEG) bio-feedback-or neurofeedback, which measures brainwaves-shows promise for attention-deficit/hyperactivity dis-order (ADHD). In the largest published controlled trial to date, 100 ADHD children underwent treatment that included the drug Ritalin, parent counseling and support at school,but 51 also received neurofeedback therapy. After one year, although allof the children showed improvement with Ritalin, only those who had also received neurofeedback treatment could sustain these gains when tested without the drug (Appl Psychophysiol Biofeedback, 2002; 27: 231-49).
EEG biofeedback is as effective as stimulant medications in improving symptoms of ADHD (Altern Med Rev, 2007; 12: 146-51), and can even raise IQ-by an average of 12 points (Appl Psycho-physiol Biofeedback, 1998; 23: 243-63).
Biofeedback may even be helpful for skin conditions such as acne. Thirty patients given 12 biofeedback-assisted relaxation and visualization sessions over six weeks saw significant reduc-tions in their acne, even compared with medication. Those who con-tinued to practise at home after the trial ended maintained their im-provement, whereas those who did not saw their acne severity return (J Psychosom Res, 1983; 27: 185-91).
Biofeedback has been applied to many aspects of stroke rehabilitation, but the results are mixed. A review of 13 studies involving 269 patients found no EMG treatment benefits (Cochrane Database Syst Res, 2007; 2: CD004585).
Nevertheless, researchers conclude that "biofeedback in general can have a very positive impact" by boosting patients' self-confidence (Top Stroke Rehabil, 2007; 14: 59-66).
Getting the feedback
In the UK, biofeedback is now available on the NHS for some conditions. To
find a provider in your area, visit the website of the Association for Applied Psychophysiology and Biofeedback at www.aapb.org.
State-of-the-art tools now allow you to carry out biofeedback in your own home. The following home-biofeedback devices, and others, are available from www.electronichealing.co.uk, www.relax-uk.com and www.mindmodulations. com (prices may vary).
- ThoughtStream (lb99): offers feedback using the galvanic skin response (GSR), represented by a light display that changes with levels of excitement or relaxation; it comes with Mental Games computer software, which allows the player to control the 'game' through sensors
- GSR 2 (lb49.99): monitors stress levels by GSR, emitting a higher or lower tone according to the emotional state- WaveRider (lb900): a Windows-based monitor collects signals from the heart, brain, muscles and skin; music and a visual display help users monitor and control their state of mind.