Fig. 1

Study Procedures. A High-definition transcranial electrical stimulation applied to the DLPFC and the current density of the effect on the brain. B Participants were given a visual working memory (VWM) task with five kinds of loads, including set sizes from 2 to 6. C Participants completed all three stages of the test, with a washout period of more than 1 week between each stage. Each stage consisted of 20 min of electrical stimulation and 40 min of assessment, and the participants received three kinds of stimulation in three stages in random order. Each participant was assessed immediately after each stimulation, including a VWM task during ERP acquisition and an auditory digit span task without ERPs. After all three sessions, a blinded questionnaire was administered