Retroactive Interference in the Recall of Simple Sentences.

A list of English sentences was learned by the method of free recall. Performance was scored both for sentences recalled precisely and for sentences recalled in content regardless of their syntactic form. Interpolated lists of sentences differing from the original list in syntactic details or in semantic form were used to produce retroactive inhibition (Rl). The Rl for semantic content was negligible; when the interpolated list differed only in syntax and preserved the semantic content of the original list the effect was facilitatory rather than inhibitory. When performance was scored for syntactic as well as semantic aspects Rl was appreciable. The results are interpreted as additional support for the hypothesis that the two aspects, semantic content and syntactic form, pose more or less distinct tasks for the learner.