Memorizing: a test of untrained mildly mentally retarded children's problem-solving.

Forty untrained mildly mentally retarded and 32 untrained nonretarded junior high school students were given eight trails of practice on a self-paced memory problem with lists of letters or words. For each trail a new list was presented, requiring ordered recall of terminal list items followed by ordered recall of initial items. Subgroups of solvers and nonsolvers were identified at each IQ level by a criterion of strict recall accuracy. Direct measures of mnemonic activity showed that over trails, solvers at both IQ levels increasingly fit a theoretically ideal memorization method. At neither IQ level did nonsolvers show similar inventions. On early trials, for both IQ levels, fit to the ideal method was uncorrelated with recall accuracy. On late trials fit and recall were highly correlated at each IQ level and across levels. The results support a problem-solving theory of individual differences in retarded and nonretarded children's memory performances.