Smith, Troy Anthony2007-09-172011-08-242007-09-172011-08-242007-09-17July 2007http://hdl.handle.net/10106/588Current theoretical accounts of feedback timing effects on retention are problematic. Some predict that delayed feedback should lead to better retention; others predict that immediate feedback should lead to better retention. Previous empirical findings are unclear: Some studies have found an advantage for delayed feedback, some an advantage for immediate feedback, and some no difference. In three experiments involving new semantic learning, I tested the extent to which spacing and lag effects can account for these seemingly contradictory findings, based on predictions of the new theory of disuse (Bjork \& Bjork, 1992). Experiment 1 compared the effects of timing variations for repeated study trials, repeated test trials, and feedback trials. Experiments 2 and 3 examined the effects of restudy and retest trials following immediate and delayed feedback, and the impact of varying study-feedback lag. Results support the spacing hypothesis and challenge competing theories of feedback timing.ENM.S.