Abstract: A method and apparatus for monitoring physiological changes in a subject wherein the method comprises the steps of placing a sensor adjacent to and spaced from the body of the subject, filtering the signal to separate frequency components lower than 4 Hz, amplifying the generated signal and displaying the amplified signal which is indicative of changes in the physiological characteristics of the subject. The apparatus senses the electromagnetic radiation emitted as generated by physiological processes and reaction to stress, and provides this information as a composite of heart rate, respiration rate, pulse amplitude and respiratory excursion. It can also be used to indicate the comparative circulation in different parts of the body, the circulation delay time and to provide information relating to the autonomic nervous response. The sensor may be placed within a bed, seat cushion or head rest so that the subject's physiological response can be measured without his being disturbed by the sensor.