Understanding macrographia in children with autism spectrum disorders

It has been consistently reported that <span class="ScopusTermHighlight">children</span> with <span class="ScopusTermHighlight">autism</span> <span class="ScopusTermHighlight">spectrum</span> <span class="ScopusTermHighlight">disorders</span> (ASD) show considerable handwriting difficulties, specifically relating to accurate and consistent letter formation, and maintaining appropriate letter size. The aim of this study was to investigate the underlying factors that contribute to these difficulties, specifically relating to motor control. <br /><br />We examined the integrity of fundamental handwriting movements and contributions of neuromotor noise in 26 <span class="ScopusTermHighlight">children</span> with ASD aged 8-13 years (IQ. >. 75), and 17 typically developing controls. <span class="ScopusTermHighlight">Children</span> wrote a series of four cursive letter l's using a graphics tablet and stylus. <br /><span class="ScopusTermHighlight"><br />Children</span> with ASD had significantly larger stroke height and width, more variable movement trajectory, and higher movement velocities. The absolute level of neuromotor noise in the velocity profiles, as measured by power spectral density analysis, was significantly higher in <span class="ScopusTermHighlight">children</span> with ASD; relatively higher neuromotor noise was found in bands >3. Hz. <br /><br />Our findings suggest that significant instability of fundamental handwriting movements, in combination with atypical biomechanical strategies, contribute to larger and less consistent handwriting in <span class="ScopusTermHighlight">children</span> with ASD.