Spacing of repetitions in the incidental and intentional free recall of pictures and words

Abstract

Lists containing repeated pictures ( PP ), repeated words ( WW ), pictures repeated as words or vice versa ( PW ), and unrepeated items were recalled following incidental, intentional control, or standard free recall instructions. Theoretical interest centered on the effects of spacing of repetitions and the degree to which the repeated events are additive (statistically independent) under different conditions. Two experiments showed that: ( a ) spacing enhanced recall for all types of repetitions under standard instructions, but only PP repetitions benefitted from spacing under incidental conditions; ( b ) under standard conditions, PP and WW repetitions were less than additive when massed but became additive when spaced, whereas PW repetitions were less than additive when massed but became additive when spaced, whereas PW repetitions were at least additive whether massed or spaced; and ( c ) most repeated events displayed independence under incidental conditions. The results implicate differential encoding and attentional processes in the lag effect, and dual coding in picture-word memory.