Effects of color stimulation on handwriting performance of children with ADHD without and with additional learning disabilities.

Active behavior problems in children with ADHD are often aggravated in situations which require sustained attention. Building on the 'optimal stimulation' hypothesis, this study explored the effects of color stimulation on graphomotor control in children with ADHD. A sample of 66 children with ADHD ( n = 19 from primary education, n = 28 children with additional speech disorders, n = 19 children with additional learning disabilities) and matched controls participated in the investigation. Subjects performed a copying task on standard white and on colored paper in balanced order across classes. Positive effects of the color stimulation on graphomotor behavior control and, consequently, on qualitative aspects of the handwritings were expected. Results broadly confirm the predictions. Effects are explained as added external stimulation facilitating behavioral inhibition and regulation of selective attention and graphomotor coordination. Reduction of visual stress as an alternative explanation is considered.