2021 Volume 22 Issue 3+4 Pages 151-157
Research has suggested that the specificity of developmental disorders is expressed in the form of letters, but the relationship between developmental disorders and writing dynamics, such as writing speed and writing pressure, has not been fully investigated. Therefore, this examined the relationship between writing dynamics and the tendencies for developmental disorders. Typically developed children and adults served as controls.
The participants were 27 children （12 boys, 15 girls, mean age = 12.4 years） enrolled in regular classes and 26 adults （15 males, 11 females, mean age = 27.3 years）. Tasks of writing from the dictation of Hiragana words were carried out. The writing dynamics data during the tasks were obtained using a pen tablet.
From the pen tablet data, we analyzed the reaction time, pen pressure, coordinates on the screen, and pen angle （vertical/horizontal component）. We also used the Autism-spectrum Quotient （AQ）, which measures the tendency for Autism Spectrum Disorder （ASD） and ADHD Rating Scale-IV （ADHD-RS）, which measures the tendency for Attention Deficit Hyperactivity Disorder （ADHD）. The results showed that the time required for writing each character was greater in children compared with adults, reflecting the influence of developmental changes. In terms of pen angle, the vertical component was larger in adults, whereas the horizontal component was larger in children, suggesting developmental changes with growth. Regarding the relationship with the tendency for developmental disorders, we found a relationship between the tendency for ASD and the writing time required per character in children. In adult males, the heavier the writing pressure, the higher the severity of communication problems. In addition, regarding the tendency for ADHD, no correlation was found with the basic parameters. Thus, our findings suggest that developmental disorders may be apparent in writing dynamics in the case of ASD.
