The Random Soldier Kinematogram: a novel tool for task-switching research in military context

Adaptive behavior in high-stakes, multitasking environments requires flexible switching between tasks with changing circumstances. However, task switching has typically been studied using static, simple, and unnoisy stimuli that are unrepresentative of most real-world operational environments. Here, we developed the Random Soldier Kinematogram (RSK), an array of moving soldiers, to better reflect the processing demands of military operational environments with dynamic, complex, and noisy stimuli. Across three experiments, we introduced RSK motion (discriminating the coherent motion direction: leftward/rightward) and color (discriminating the majority uniform color: khaki/white) tasks, by examining their cognitive-control demands in single-task blocks (Experiments 1 and 2) and a task-switching context (Experiment 3). Experiment 1 ruled out the possibility that perceptual differences between uniform colors involved different discrimination performances. Experiment 2 orthogonally varied motion coherence and color coherence to gain insight into participants' sensitivity to target (task-relevant) and distractor (task-irrelevant) information. Results showed unequal task strength, with a motion task that is less control-demanding (dominant) and a color task that is more control-demanding (non-dominant), to overcome interference from motion. Experiment 3 investigated the efficiency of cognitive control processes involved in switching between RSK tasks (switch costs) and maintaining competing task-sets (mixing costs). Asymmetric switch cost was found, with larger cost when switching to the motion (dominant) task, since stronger cognitive effort was necessary to release it from its backward inhibition. We conclude that RSK expands possibilities for task-switching research in the military by better sampling soldiers' surrounding informational constraints with adjustable signal-to-noise ratios of task-relevant and task-irrelevant information.