A Tablet-based Application to Study the Speed-Accuracy Tradeoff in Handwriting throughout Lifespan

Handwriting is a complex gesture whose monitoring can disclose age-related modifications or the presence of frailty conditions throughout lifespan. An important biomarker that has the potential to detect subtle yet relevant changes in motor tasks is the Speed-Accuracy tradeoff (SAT). Due to the complexity of handwriting, SAT still lacks a quantitative modeling in this domain. Our aim is to leverage a consumer tablet technology to develop an application to assess SAT in handwriting, through the Steering law. The developed app was tested on four age groups: preschoolers, grade-schoolers, adults, and elderlies. We found that SAT effectively differentiated between age groups, with a significant developing trend from early childhood to adulthood, and a significant regression to primary school levels at an elder age. We conclude that our application is useful to characterize SAT in handwriting throughout lifespan. Because of its sensitivity, future work should investigate the ability of the devised app to anticipate the insurgence of potential frailty conditions, due to ageing or pathology.