Personality Types A, B and C

Biofeedback

Biofeedback is a technique in which individuals receive real-time electronic feedback about their own physiological processes — enabling them to learn voluntary control over these processes through operant conditioning principles. It is used in the treatment of stress-related conditions including hypertension, tension headaches, migraine, chronic pain, anxiety, and insomnia.

How Biofeedback Works

Physiological processes that are normally outside conscious awareness and voluntary control — such as heart rate, blood pressure, muscle tension, skin temperature, electrical conductance of the skin (galvanic skin response, GSR), and brainwave activity (EEG) — are monitored by electronic sensors. The signals are converted to a real-time display that the patient can observe: a visual bar, a tone that changes pitch, or a number on a screen. By observing this feedback whilst attempting various relaxation or mental strategies, patients gradually learn to modify the physiological response in the desired direction — reducing muscle tension, lowering heart rate, or raising skin temperature (which indicates reduced sympathetic arousal).

The mechanism of learning is operant conditioning: successful reduction in physiological arousal is immediately signalled by the biofeedback display, providing reinforcement. Over multiple sessions, the patient develops increased awareness of subtle internal states and the cognitive-behavioural strategies that reliably modify them. Eventually the skills can be applied without the equipment.

Types of Biofeedback

• EMG (electromyography) biofeedback: measures muscle tension via surface electrodes. Used for tension headaches, back pain, anxiety, jaw clenching (bruxism).
• EEG (electroencephalography) biofeedback (neurofeedback): monitors brainwave patterns. Used for anxiety, ADHD, insomnia.
• Thermal biofeedback: monitors skin temperature (peripheral vasoconstriction reduces temperature; sympathetic relaxation increases it). Used for Raynaud's disease, migraine.
• Galvanic skin response (GSR) biofeedback: monitors sweat gland activity — an index of sympathetic arousal. Used for anxiety and stress.
• Heart rate variability (HRV) biofeedback: monitors the variability in intervals between heartbeats. High HRV is associated with good autonomic flexibility; HRV biofeedback is used for anxiety, post-traumatic stress, and cardiac rehabilitation.

Research Evidence

Budzynski et al. (1970) conducted an early controlled trial of EMG biofeedback for tension headaches. Participants in the biofeedback group received real-time feedback about frontalis muscle tension and were trained to reduce it. Compared with a pseudo-feedback control group and a no-treatment control, the biofeedback group showed significantly reduced muscle tension and significantly reduced headache frequency and severity. This was an important early demonstration of biofeedback efficacy in a controlled design.

Freedman et al. (1991) demonstrated that thermal biofeedback was effective for Raynaud's disease (a condition in which cold and stress trigger excessive vasoconstriction) — patients trained to raise finger temperature showed significantly fewer and less severe vasospastic attacks than controls.

Evaluation

Biofeedback has the important clinical advantage of producing no known serious side effects — it is a non-pharmacological intervention that does not carry the risks of drug therapies. It can teach genuine physiological self-regulation skills that generalise beyond the therapy room. Limitations: biofeedback equipment is expensive; sessions require specialist training and facilities; it is not widely available within routine NHS services. Some research suggests that the relaxation techniques taught alongside biofeedback (rather than the feedback itself) may be the primary active ingredient — making biofeedback's specific advantage over simpler relaxation training unclear. Miller and Brucker (1979) demonstrated that the specificity of biofeedback learning may be limited — some physiological control may generalise beyond the specific response trained. Access and cost remain significant barriers to routine use.