Handwriting Isochrony in Autistic and Non-Autistic Children
Year: 2026
Type: article
Abstract: Handwriting difficulties are frequently reported in autistic children and may interfere with academic performance. However, whether fundamental motor principles such as isochrony are preserved in autism remains largely unexplored. To address this question, fifty-five autistic and fifty-nine age-matched non-autistic children (6–12 years), all with intellectual functioning within the normal range, traced the letter “e” at five different sizes on a graphic tablet. Kinematic data were analyzed using the power law MT = T₀ × A γ , where MT is movement time, A the amplitude of “e”, T₀ the baseline time and γ the degree of isochrony. Because reliable estimation of isochrony parameters requires an adequately expressed amplitude-duration relationship, only participants whose data adequately fitted the power law (R² > 0.36) were retained for parameter analyses. In total, twenty-four autistic and thirty-six non-autistic children met this criterion. Frequentist and Bayesian analyses revealed no group differences in the degree of isochrony (γ = 0.45) or baseline time (T₀ = 1.66 s), indicating comparable temporal scaling of handwriting movements from age six among autistic and non-autistic children with a reliable amplitude-duration relationship. Present findings suggest that isochrony control can be preserved in a subgroup of autistic children whose data adequately fit the power-law model. Handwriting difficulties in autism are not necessarily attributable to impaired fundamental motor timing mechanisms and may involve other processes.
Source: Research in Autism
Institutions: Université de Tours, Centre National de la Recherche Scientifique, Université de Poitiers, Centre Hospitalier Universitaire de Tours, Thion Medical (France), Université de Bretagne Occidentale, Université de Bretagne Sud, Laboratoire des Sciences et Techniques de l’Information de la Communication et de la Connaissance, Université de Bordeaux, Centre Hospitalier Universitaire de Limoges, Centre Hospitalier de La Rochelle, Inserm, Université de Limoges, Centre Hospitalier Charles Perrens, Institut Universitaire de France
Language: English
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,410
OpenAlex ID: W7222818646