Determinants of rate of extinction in successive acquisitions and extinctions

Abstract

Rats were used in an investigation of the conditions that are necessary to obtain a decrease in resistance to extinction across extinctions in a successive acquisition and extinction paradigm. Long breaks (23.5 h) after extinction coupled with a short intertrial interval within extinction sessions (long N-R transition) resulted in a decrease in resistance to extinction across the successive extinctions. Long breaks after acquisition sessions (long R-N transition), or in the middle of acquisition sessions (long R-R transition), yielded an increase in resistance to extinction across the successive extinction sessions. When extinction sessions followed immediately after acquisition sessions (N-R), Ss decreased their running speeds within each of the successive extinctions. When acquisition sessions followed immediately after extinction sessions (R-N), Ss decreased their running speeds within the first few successive extinctions. The R-N Ss learned to increase their running speed within extinctions during the later successive extinctions.