Conditioning as a function of the time between conditioned and unconditioned stimuli.

Abstract

Six groups of human subjects were conditioned in an eyelid conditioning situation at interstimulus intervals of 100 msec, 200 msec, 225 msec, 250 msec, 300 msec, and 400 msec Results of the investigation indicate that the length of this interval is one of the variables determining the asymptote of the conditioning curve. For the range of intervals used in this study, the final level of conditioning seems to be an increasing negatively accelerated function of the length of the interval. The rate of conditioning is also an increasing negatively accelerated function of the same variable. These results confirm the purely mathematical definition of Hull''s construct, stimulus trace, and, at the same time, throw doubt on his added neurophysiological speculations about the same concept.