Effect of familiarity on primacy performance of normal and retarded children.

On the assumption that serial recall tasks reflect spatial memory rather than verbal rehearsal, the purpose of this experiment was to determine what effect stimulus familiarity had on the spatial primacy performance of 20 retarded and 20 normal boys and girls. Linear presentation effects of familiar and nonfamiliar pictures upon serial position curve performance when overt verbalization was suppressed were investigated. Results indicated that an interaction of stimulus familiarity and spatial memory is responsible for the primacy effect found in serial position curves. No primacy effect for either the normal or retardate group was found in the nonfamiliar stimulus condition. No overall developmental effects were found between groups of children on serial position performance. Consistent with Craik and Lockhart's memory processing model, the present results indicated stimulus familiarity provided deeper levels of processing, thereby facilitating primacy effects.