How does enactment affect the ability to follow instructions in working memory?

Recent studies examining working memory for sequences of instructions have demonstrated a performance advantage when instructions are physically enacted rather than verbally recalled. However, little is known about the source of this effect, or how instructions are stored in working memory more generally. In particular, no previous studies have compared impacts of enactment on encoding vs. recall in working memory. We conducted an experiment to examine the impact of enactment on both the encoding and recall phases of a task measuring memory for sequences of simple action-object pairs (e.g. touch the circle, spin the cross, flip the square...) in young adult participants. An advantage for enacted over verbal recall was observed, in line with recent evidence. In addition, enactment of actions during the encoding phase on each trial significantly facilitated subsequent performance; this effect was particularly apparent for verbal repetition rather than enacted recall. These findings are interpreted as reflecting a beneficial role for spatial-motoric coding in working memory, that can be engaged either through action planning or physical performance.