biofeedback(redirected from electromyographic biofeedback)
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Biofeedback(religion, spiritualism, and occult)
Biofeedback is the measurement of brain wave activity indicative of the depth of a trance, among other things. The principle behind biofeedback is that by providing the individual with knowledge of his or her internal body processes, these processes can be consciously controlled. Using biofeedback instruments, the operator can consciously modify his or her brainwave activity, heart rate, blood pressure, and skin resistance. This can be useful in relaxing into a deeper state of trance. The practice of using biofeedback machines was first introduced in the United States by Joe Kamiya, as reported in Psychology Today (April 1968, v. 1, no. 11). Biofeedback can use many tools: EEGs (electroencephalograms) to measure brain waves, EKGs (electrocardiograms) to graph heart processes, GSRs (galvanic skin responses) to measure skin responses, and EMGs (electromyographs) to check muscle tensions.
Biofeedback deals with the alpha waves (8-13 cycles per second frequency), beta waves (14-50 cycles), theta waves (4-8 cycles), and delta waves (0.5-4 cycles). The American Society for Psychical Research found that biofeedback can be effective in bringing the psi faculty under control. The beta frequency is the normal waking state but by relaxing—using such techniques as meditation, massage, yoga, or hypnosis—it is relatively easy to descend into the alpha state. Psychologists use biofeedback to help their patients cope with pain. Physical therapists use it to help stroke victims regain movement in paralyzed muscles.
In a typical biofeedback session, the subject has electrodes connected to the back of the head, the right forearm, and two fingers of the right hand. A respiration gauge may also be worn. These electrodes detect any changes in internal states and relay them back to the subject by way of lights, moving needles, or sounds. The Silva Mind Control organization, founded by José Silva (1914–1999) in the 1960s, conducted sessions leading to what they termed “functioning in the alpha.” It emphasized positive thinking, self-hypnosis, and visualization.