INTENDING TO FORGET - THE DEVELOPMENT OF COGNITIVE INHIBITION IN DIRECTED FORGETTING

The thesis of this research is that children's cognitive inhibition in creases in efficiency with age over the middle childhood years, and th is increasing efficiency contributes to developmental improvements in memory performance. To explore this thesis, the development of efficie nt retrieval inhibition, defined as the suppression of activation and retrieval paths to information stored in long-term memory, was investi gated. In Experiment 1, first. third, and fifth graders and adults par ticipated in a directed-forgetting experiment. Using a blocked-cuing p rocedure, subjects were given a ''forget'' or ''remember'' cue halfway through an unrelated free-recall list. At recall, subjects were asked either to remember all the words (even the ones they had been instruc ted to forget) or to remember only to-be-remembered words. The results suggested that the ability to intentionally inhibit the maintenance a nd recall of irrelevant information improves gradually over the elemen tary school years, but is not fully mature by fifth grade. Children we re less able than adults to inhibit the to-be-forgotten words, and the y were less able to withhold production of remembered to-be-forgotten words than were adults. Experiment 2 replicated the developmental effe cts found in the first experiment and demonstrated that the developmen tal differences in performance were due to differences in mnemonic pro cessing rather than differences in the ability to understand the instr uctions of the task. (C) 1996 Academic Press, Inc.