[Influences of environmental-context changes on rehearsal effects in episodic memory]

Does rehearsal facilitate association between to-be-remembered items and environmental context (EC) as well as it strengthen the individual traces of items? The answer from the present experiment was affirmative. Subjects, 183 undergraduates, studied a list of 15 familiar nouns by rehearsing aloud with a subsidiary task, and then received a free recall test under one of three conditions: immediate recall (IM), same context (SC), and different context (DC). Subjects in IM were tested immediately after the study session, while the other subjects were tested 24 hours after the study session. The tests in IM and SC were conducted at the same place with the same experimenter after the same subsidiary task as the study session, whereas the test in DC were conducted at a different place with a different experimenter without the task. The magnitudes in DC of the effect of the number of rehearsals on free recall were about one-half of those in IM and SC, whereas the magnitudes in IM were nearly identical to those in SC. The results indicate that the rehearsal effect is one of EC-dependent phenomena.