An exploratory study of relationships between the executive functions and spatiotemporal control in a complex motor task: the spatial tapping task

Executive functions (EFs) are cognitive processes enabling planning, control, and regulation of behavior. A variety of tasks have been developed to evaluate EFs, from complex reasoning to simpler inhibition tasks, reflecting the diversity of symptoms observed in patients with executive deficits. Recent research has emphasized their unity, proposing three core functions, working memory, inhibition, and switching, that share resources and combine to enable complex tasks. Yet, no single task captures both the unity and diversity of EFs, limiting the development of a unified framework and a balanced assessment. To address this gap, we designed the spatial tapping task, a timing paradigm combining finger tapping and circle drawing. Finger tapping requires working memory for explicit timing control, whereas circle drawing requires anticipatory control akin to switching to control movement trajectory, enabling implicit timing control. Participants produce taps along a circular trajectory with the tempo increasing progressively. A slow tempo favors discrete movements with long pauses between taps, whereas a fast tempo promotes continuous motion. Previous analyses supported a change in timing control mode with increasing tempo. Here, we explored the hypothesis that EFs are engaged accordingly: working memory in the slow/discrete phase, switching in the fast/continuous phase, and inhibition in the intermediate phase, where demands for continuous motion increase. In two studies combined into a single dataset, we compared scores with those from neuropsychological tests using correlations. We found that timing accuracy in the slow/discrete phase was associated with working memory, spatial accuracy in the fast/continuous phase with switching, and longer contact time in the intermediate phase with inhibition. We also explored whether performance was consistent with the EF deficits described in the literature, and the potential contribution of motor output, reporting scores obtained across populations with executive deficits (aging and dementia), combined executive and motor impairments (schizophrenia), and motor expertise (biscriptual writers), along with matched controls. Findings were consistent, although often more specific, and highlighted an important contribution of motor output. Altogether, our results provide initial evidence that the task can be used to investigate EFs, although cognitive, motor, and sensory contributions need to be disentangled to improve its specificity.