The pseudo-conditioned eye-lid response.

Abstract

Pseudoconditioned eyelid responses to light and 3 different auditory stimuli were developed in 31 subjects following repetitive stimulation with a strong unconditioned stimulus (puff of air to the cornea) alone. Somewhat similar responses were observed in a control group of 30 subjects, each of whom sat and fixated a lighted screen for the same period of time taken up by the puff stimulation in the experimental group. The pseudo-conditioned eyelid responses showed some over-night decrement in frequency of occurrence, but there was reliable retention over a period of more than a wk., and the responses were very resistant to extinction. The pseudo-conditioned eyelid responses seemed to resemble previously reported conditioned eyelid responses in amplitude, latency, and frequency increment. The frequency of pseudo-conditioned responses was not dependent upon the intensity of auditory stimulation within the range tested; this was not true of the frequency of the primary reflexes to sound. There was no evidence of sensitization of the primary reflexes to light and sound.