one screening day and two experimental test days involving sham and frontotemporal antiphase theta-tuned HD-tACS (counterbalanced across subjects), in which the behavior of younger adults was recorded “online” (i.e., during the 10-block delivery period of sham or active stimulation). Experiment 4 involved re-recruiting poor performing younger adults from Experiment 1 and running them through the frontotemporal inphase theta-tuned HD-tACS condition using a 10-block pre-stimulation baseline, 10-block stimulation period, and 10-block post-stimulation period.
