A deduction from an excitation-inhibition account of retroactive inhibition.

Abstract

Fifty-five human subjects practiced 2 paired-associate lists of 6 items each. The stimulus terms for these lists consisted of signals of the international Morse Code and the response terms of written letters of the alphabet. Two experimental groups practiced the 2 paired-associate lists in opposite order from each other. When subjects were tested with all 12 paired associates immediately after practice with the 2d list, the performance data supported the following conclusions: (1) between-list errors were more frequently made to stimulus terms of the first -practiced list than to stimulus terms of the list which was 2d in the practice order; (2) correct responses and with-in-list errors were more frequently made to the stimulus terms of the paired-associate list which was practiced last. Both of these effects diminished to a considerable degree during a 21-hour post-practice rest period. Retroactive inhibition depends, to an important degree, on the inhibition of overt or covert original list responses during practice with the interpolated list. This inhibition decays in time. The general results support an excitation-inhibition account of paired-associate learning.