Exploratory outcome measures
In addition to our primary outcome measures assessing multitasking, sustained attention, and working memory, we also collected data from four other ACE-X tasks to be used in an exploratory analysis of other aspects of attentional control: (1) Boxed, a visual search interference processing based on the visual search paradigmBoxed is a forced-voice task with four stimuli conditions of 20 trials each: set size of four or 12 and feature or congruent stimuli. The stimuli are colored landolt squares (red and green) with side openings (left, right, bottom, or top) and participants are instructed to attend to the green with top or bottom openings (target) and ignore all other red and green squares. Participants respond to whether the target has an opening on the top or bottom. The feature four condition includes one green target and three red distractors. Feature 12 includes 11 red distractors and one green target. Conjunction four includes the green target, green distractor, and two red distractors. Conjunction 12 includes the green target, six red distractors, and five green distractors.Color tricker, based on the Stroop taskFlanker is designed to measure selective attention and interference resolution performance. Participants view an array of five arrows and are instructed to identify the direction of a central arrow (target) surrounded by four flanking arrows (distractors). In congruent trials (14 trials) the center arrow points the same direction as the four flanking arrows and in incongruent trials (14 trials) the target arrow points in the opposite direction as the four flanking arrows. Trial types are mixed pseudo randomly such that no more than three trials in a row are the same condition.Compass is based on the Posner cueing paradigmOn all adaptive ACE-X tasks, the window to respond was adaptive based on accuracy from the previous trial. This allows for the same tasks to be used in a range of participants that vary in age and clinical condition. If the participant is correct and responds quickly enough, the response window decreases by 10 ms. If the participant responds incorrectly or too slow, the response window increases by 40 ms. The minimum response window floor is 150 ms. For all adaptive modules, the inter-trial interval was 800–1200 ms and feedback occurred for 200 ms post response.