The Effect of the Intensity of UCS upon Eyelid Conditioning

The earliest investigation concerning the effect of the intensity of UCS upon eyelid conditioning was made by Passey (1948). He found that the rate of the acquisition of conditioned responses exhibited some logarithmic function to the intensity of the UCS. Spence constructed a hypothetical emotional response, re, which was assumed to be the drive level, D, in the case of aversive conditioning as an intervening variable to explain his experiment and some later studies (1951, 1953, 1956, 1958). The hypothetical emotional, re, was further assumed and elaborated to be parallel with the activity which was aroused by aversive stimulation. From the observable physiological evidences, the magnitude of reflexes to the stressful stimulus is some function of the intensity of the stimulation.