The problem posed by this study was to determine a method of presenting information that would maximize learning, by taking into account the learner's conceptual tempo, one aspect of his cognitive style. Specifically, this study investigated the possible interaction effects of the learner's impulsive-reflective disposition with the rehearsal part and standard methods of presenting material in a multi-trial free recall learning paradigm. The study also reviews the literature regarding the results of differentiated instruction for different characteristics of learners, commonly referred to as aptitude-treatment interaction (ATI). The major hypothesis of the study which expected a significant interaction between methods of presenting the free recall learning task and the conceptual tempo of the learner was not confirmed, due to the lack of sufficient uniqueness in the three treatments to elicit differentiated effects of reflective and impulsive subjects. (Author/LAA)