BIOFEEDBACK REPORT

The parameter used in biofeedback tests and therapy is known to yield data about the functioning of the Autonomic nervous system (ANS). Four such parameters were selected for the tests on Mr. M. K. Trivedi. These were galvanic skin response (GSR), pulse rate (PUL), peripheral skin temperature (TEM) and surface electromyograph (EMG) of striated muscles.

The galvanic skin response is determined by measuring the galvanic skin conductance. This is correlated with the activity of the sweat glands and is regarded as a measure of autonomic arousal; a pointer to the emotional state of the subject. As sweat gland secretion increases, there is an increase in conductivity, pointing to higher stress, while decreased values of GSR have been correlated with a state of relaxation and meditation.

The pulse rate, which is directly connected to heart rate variability, is interpreted as an indicator of the stress being perceived by the subject at the time of the testing. The EMG is the recording of muscle action potentials with skin surface electrodes, and is used as an indicator of muscle recruitment or muscular tension. Stimulation of the sympathetic nervous system under stress is known to bring about an increase in muscular tension as the body readies for ‘fight or flight’ response. The blood flow to the brain also increases in such a situation, with accompanying vasoconstriction in peripheral blood vessels as the body attempts to conserve resources. This results in a corresponding drop in peripheral skin temperature.

Thus an increase in sympathetic nervous system activity when a situation of stress is perceived can be expected to result in decreased TEM and increased GSR, PUL and in the muscular tension as measured by the EMG. With increase in activity of the parasympathetic nervous system, on the other hand, the four parameters can be expected to respond in the reverse manner as the body parameters are restored and the body starts returning towards a state of rest.

A measure of the above four parameters was taken in the Mr.Trivedi’s case to determine whether any data is generated which is inconsistent or abnormal in any way.

After the analysis of these four parameters, the analyzed data indicated that Mr.Trivedi’s Autonomic nervous system was simultaneously found to be in the highest state of excitement (sympathetic part of the Autonomic nervous system) and the highest state of calmness (parasympathetic part of the Autonomic nervous system).

Dr Costello stated that “Mr.Trivedi’s measurements were uniquely dissimilar from any other administered to patients and non-patient samples (1979 until 2004).”