[Finger vasomotor, heart rate, and electrodermal measures of orienting and defensive reflexes (author's transl)].

The present study was carried out to differentiate orienting reflexes (OR) from defensive reflexes (DR) using 20 female college students as Ss. All Ss received 5 stimulations of 1 sec weak tone (1000 Hz, 40 dB) and 5 stimulation of 1 sec strong tone (white noise, 100 dB) in a randomized order and time interval. Finger pulse amplitude (PA), finger blood content (BC), heart rate (HR), and palmar skin potential reflex (SPR) were recorded simultaneously. BC decrease, HR deceleration, and negative wave of SPR occurred to weak stimulations, while increase, acceleration, and positive wave occurred to strong stimulations. Both intensities of stimulation produced a decrease in PA. These results were discussed in relation to the autonomic changes involved in OR and DR.