Conditioning of the nictitating membrane in the frog, Rana P. Pipiens.

Abstract

A method is described for rapid conditioning of the eyelid reflex of the frog. The CS is a light touch behind the nostril; the US is a light touch on the cornea of the same side. A trace interval of 2 sec. leads to faster conditioning than 1/2 sec., and produces CRs on two-thirds of the trials on the third daily block of 25 trials. Extinction and relearning are prompt There is immediate transfer to the contralateral side. Control tests with CS alone and US alone rule out habituation and sensitization as explanations.