Intersession delay and avoidance extinction to training and generalization stimuli

Abstract

Independent groups of albino rabbits were trained to an avoidance criterion using a 1000 cps pure tone CS. Independent subgroups were extinguished with tones of 1000, 2000, or 4000 cps either. 5, 12, 24, or 48 h after training. Resistance to extinction for 1000 cps was least after a. 5 h intersession delay (ISD) and greatest after 24 h ISD did not affect extinction in the 2000 cps groups. For 4000 cps, resistance remained low for the three brief ISDs and then increased after 48 h. These results are assumed to reflect a differential rate of increase over time in generalization to other CS values, versus apparatus stimuli.