Figure 1. Experiment 1, interference between word-list and motor skill learning.

(a.) Participants learned a word-list and a motor skill in quick succession, TMS (to DLPFC or M1) or sham stimulation was applied and twelve hours later participants word recall and motor skill was retested. (b.) Word recall was impaired by the motor skill-learning task despite sham or real stimulation to M1 (box ± s.e.m.). In contrast, applying TMS to the DLPFC prevented the impairment of word recall by the motor skill learning task. Preventing the interference between the tasks was not dependent on disrupting the interfering memory because motor skill changes were not significantly different across the groups (box ± s.e.m.). (c.) The relationship between the tasks was affected by stimulation. There was a significant correlation between the decrease in word recall and initial motor skill following M1 stimulation; whereas, there was no significant correlation following DLPFC stimulation. The correlation following M1 stimulation was significantly greater than the correlation following DLPFC stimulation (see above R² values).