The effects of proactive and retroactive demonstrations on learning signed letters

Four groups of adults learned letters of the American manual alphabet with augmented information (demonstrations) provided by a model. The model was presented either before (proactive) or after (retroactive) attempted performances of the letter handshapes, thereby providing different learning contexts. Acquisition performance was enhanced when the demonstrations were presented immediately prior to performance, and degraded when the demonstrations followed performance. Same day and delayed (48 h) retention tests without augmented information revealed a large drop in performance for the proactive groups and a slight improvement in performance for the retroactive groups. These findings are compared to related effects which suggest that augmented information has both negative and positive influences on learning.