Effects of verbal labeling on memory for hand movements.

This study examined whether a secondary verbal shadowing task influences recall for hand movements. Descriptive verbal labels associated with hand postures (e.g., "fist", "palm") were presented auditorily, concurrent with video presentation of hand postures, and the participant was instructed to shadow the words aloud. In the congruent verbal labels condition, the words were matched with the hand postures shown, and in the incongruent condition, the labels and hand postures were unmatched. In Experiment 1 (N = 18), a computerized version of the Kaufman Hand Movements Test (KHMT), which involves three distinct hand postures, was performed under congruent and incongruent labels conditions, and baseline. For Experiment 2 (N = 18), the same format was applied to a hand movement span task, similar to the KHMT, but based on seven distinct hand postures. For both experiments, shadowing congruent labels enhanced serial recall, whereas shadowing incongruent labels reduced recall when compared to baseline. Thus memory for hand movements was affected by the content of the secondary verbal task, consistent with participants spontaneously using a verbal recoding and rehearsal strategy to support this form of memory, a strategy enhanced through the provision of appropriate labels.