Theoretical Implications of the Spacing Effect 1

Abstract

Interest in the effects on memory of the temporal distribution of study trials goes back to some of the very first memory experiments. Jost (1897) noted a facilitative effect of the spacing of learning trials in Ebbinghaus’s data, and set out to study it systematically. More than sixty years later, Underwood (1961) was compelled by a large body of experimental evidence to conclude that “Facilitation by distributed practice in verbal learning occurs only under a highly specific set of conditions, and the magnitude of the effect when it does occur is relatively small [p. 230] .” Today, with interest focused more on the learning of individual items than on the acquisition of multi-item lists, and with study and test trials for a particular to-be-remembered item routinely separated, the conclusion is quite different. The effect on retention of the spacing of repetitions is large, and the number of different conditions under which it occurs is truly remarkable.

Topics & Concepts