Level of initial training moderates the effects of distributing practice over multiple days with expanding, contracting, and uniform schedules: Evidence for study-phase retrieval.

Inconsistent results have been obtained in experiments comparing the effects on retention of expanding, contracting, and uniform practice schedules, in which the spacing between successive practice sessions progressively increases, progressively decreases, or remains constant, respectively. In the present study, we experimentally assessed an apparent trend in the literature for expanding schedules to be more advantageous than other schedules following a low level of training during the initial learning session, but not following a high level of initial training. College students studied pseudocword-word pairs in multiple practice sessions distributed over a 13-day period according to expanding, contracting, and uniform schedules. During their initial learning session, participants received either low-level training (two study trials) or high-level training (one study trial and then five rounds of practice testing with corrective feedback). All participants were treated identically in the subsequent practice sessions. A final cued-recall test after a two-week retention interval revealed an expanding-schedule superiority following low-level initial training but not following high-level initial training. These results are interpreted in terms of a study-phase-retrieval mechanism and help explain the mixed results obtained in the prior literature.