Gamified cognitive tests
visuo-spatial working memory task, orthostasis
BRAIN
Participants completed gamified cognitive tests via a tablet (iPad, Apple Inc.) loaded with the Brain Lab application by Statespace Labs Inc., New York, NY, USA. Gamified cognitive tests were completed in bouts of 5 rounds of the three gamified cognitive tests (Gridshot, Capacity, and Multitracker). During experimental trials gamified cognitive tests were block randomized, so that there were 5 blocks with each block containing 1 round of each gamified cognitive test (Gridshot, Capacity, and Multitracker). Each gamified cognitive test is a 60-second test that provides immediate feedback to the participant upon completion by providing the player a composite score for the test. All gamified cognitive tests were completed in the upright, standing position, as orthostasis may provide a greater circulatory challenge [Gridshot is a first-person shooter stylistic test that presents three targets of the same size simultaneously, with a new target appearing after one target is destroyed. The player destroys a target by aiming and shooting targets as quickly as possible. This test requires quick movements to align onto the target stimulus at small, medium, and long ranges. This test assesses the performance metrics of number of hits, misses, hit rate (percentage of shots attempts that successfully hit target, %), hits per second (number of targets successfully hit per second), shots per second, median time to hit (median time between consecutive hits, second), shot precision (the variability of the shot locations relative to the center of the targets) and a composite score (a weighted proprietary score based on the aforementioned metrics). Gridshot is further described by Listman et al. [Capacity is a novel visuo-spatial working memory task that requires participants to complete a series of trials where multiple targets appear on the screen at once in varying colors. The targets disappear briefly and when they reappear, one target has changed color. The participants have to identify and tap the target that changed color. Difficulty of the test is modulated by the number of targets that appear on the screen through the addition or subtraction of one target based on a previous correct or incorrect response, respectively. This test assessed the performance metrics of number of correct trials completed, the number of incorrect trials completed, proportion of correct trials (the proportion of correct trials out of total trials completed, %), median time to hit (time from target reappearance to target selection, s), mean difficulty, and a composite score (a weighted proprietary score based on the aforementioned metrics). Capacity is described further by La Monica et al. [Multitracker is a novel selective attention test that requires participants complete a series of trials, where multiple orbs (12) appear in the same color (Blue). A subset of the orbs (2–6) briefly change color (Red), marking them as the target orbs that the participant must track and identify at the end of the trial. After the orbs change back to blue, all orbs move randomly for a few seconds. When the orbs stop the participant is tasked with identifying the new location of each target orb by taping on each one individually. Difficulty of the test is modulated during the trials by changing orb movement speed (by increasing if participant identified all orbs correctly or decreasing speed if a distractor orb was selected) or by adding additional target orbs to be tracked. This test assessed the performance metrics of number of correct trials completed, the number of incorrect trials completed, proportion of correct trials (the proportion of correct trials out of total trials completed, %), median time to hit (time from reappearance to target selection, s), mean difficulty, and a composite score (a weighted proprietary score based on the aforementioned metrics).Gameplay for all three gamified cognitive tests were the same during practice and experimental trials (as described above), except that an adaptive procedure was used to adjust task difficulty practice sessions to determine a personalized baseline level for Capacity and Multitracker. Specifically, the adaptive procedure manipulated variables included number of orbs for Capacity or movement speed of orbs for Multitracker. Difficulty was increased after each correct response and decreased after each incorrect response. During the experimental trials, in an effort to standardize performance, lab personnel reviewed the performances from practice session three and locked in a personalized baseline for all experimental trials.