design appears in a location already occupied in that block. On average, 3 of the 10 trials in each block are repeat locations, and repeats are 2-back. In the vigilance condition, the same stimuli are presented in the same locations, but a dot appears above figures on 30% of trials, and participants are to press a button when a dot appears. The purpose of the vigilance condition is to control for simple motor and attention processes involved in the SWM condition. In both conditions, stimuli are presented for 1,000 ms, and each interstimulus interval is 1,000 ms (total time: 7 minutes, 48 seconds). Upon completion, participants and parents are financially compensated for their time.
