Reactive inhibition theory and intertrial correlations

From certain theoretical properties of Hull's reactive inhibition and from the known modest reliability of reminiscence measures, it follows that intertrial correlations among psychomotor test scores should be higher under distributed-practice conditions than under massed-practice conditions. This proposition was tested in a conventional practice distribution paradigm involving 168 Caucasian subjects. Bartlett's test for the homogeneity of covariance matrices confirmed the prediction, and a sign test for matched correlation pairs showed that correlations in the distributed practice mode were significantly more often higher than those in the massed practice mode. These results refute the prevailing view that intertrial correlations are invariant with respect to practice distribution, and they strengthen the credibility of Hull's principle of reactive inhibition.