Handwriting speed and pen motor control in older adults with and without cognitive impairment

Abstract

Background – Handwriting is a hierarchical cognitive–motor activity requiring the integration of motor execution, visuospatial processing, working memory, and executive control. Digital handwriting technology enables simultaneous assessment of process (kinematics) and product (performance outcomes), offering a theoretically grounded approach to detecting cognitive vulnerability in aging. Methods – This study examined whether kinematic handwriting features differentiate institutionalized older adults with and without cognitive impairment and whether these features predict handwriting product performance under varying cognitive–motor demands. Fifty-eight participants (20 cognitively healthy; 38 cognitively impaired), classified using education-adjusted MMSE cutoffs, completed pen-control tasks (DOTS, LINES) and four handwriting-speed tasks (two copy, two dictation) on a digitizing tablet. Nine standardized kinematic variables were analyzed using logistic and multiple linear regression models with correction for multiple comparisons. Results – Pen-control tasks (DOTS, LINES) did not significantly discriminate between the two groups, the handwriting-speed tasks, particularly dictation, revealed significant group differences. Temporal efficiency and stroke organization variables (e.g., Duration, Number of Strokes) significantly contributed to classification in high-demand tasks. Among cognitively healthy participants, associations between kinematic and product measures were limited, suggesting preserved compensatory mechanisms. Conversely, cognitively impaired individuals exhibited stronger process–product coupling, with Start Time, Vertical Size, and Duration significantly predicting handwriting performance in dictation tasks. Conclusion – Handwriting kinematics, especially temporal and stroke-related features, are sensitive indicators of cognitive impairment when assessed under high cognitive–motor load. These findings support the use of digitally mediated handwriting tasks—particularly dictation paradigms—as ecologically valid, low-cost tools for screening and monitoring cognitive decline in older adults. Clinical trial registration – ClinicalTrials.gov, NCT06483438.