Biofeedback system with interchangeable modules for applied research and clinical practice using microcomputer interface

The authors describe the design and construction of an electronic system to perform biofeedback studies. The system consists of interchangeable modules that will permit the measurement of a greater number of variables. It also makes possible future modifications in such modules. The authors used previously designed modules for the management of (1) body temperature; (2) psychogalvanic skin reflex; (3) heart rate; (4) respiratory rate; (5) electromyographic activity; and (6) electroencephalographic activity. The system is equipped with a two-channel cassette recorder modified to store the information on bioelectric activity for microcomputer analysis. A TV monitor is used to reproduce the EEG information in a picture with a square form, whose size changes when alpha activity appears.<>