Cambridge Journals Online

Bimanual coordination in alcohol-exposed children: Role of the corpus callosum

TRESA M.  ROEBUCK-SPENCER  a1 , SARAH N.  MATTSON  a2 , SARAH DEBOARD  MARION  a3 , WARREN S.  BROWN  a3 and EDWARD P.  RILEY  a2 c1 a1 National Rehabilitation Hospital, Washington, DC 20010 a2 Center for Behavioral Teratology, San Diego, CA 92120 a3 Travis Research Institute, Fuller Graduate School of Psychology, Pasadena, CA

Article author query roebuck-spencer tm     mattson sn     marion sd     brown ws     riley ep

Abstract

The corpus callosum (CC) is one of several brain structures affected in children prenatally exposed to alcohol. This structure plays a major role in coordinating motor activity from opposite sides of the body, and deficits in bimanual coordination have been documented in individuals with agenesis of or damage to the CC, particularly when the task is performed without visual feedback. The Bimanual Coordination Test was used to assess speed and accuracy on a task where both hands must coordinate to guide a cursor through angled pathways providing measures of interhemispheric interaction or the ability of the two hemispheres to coordinate activity via the corpus callosum. Twenty-one children with fetal alcohol spectrum disorders (FASD) and 17 non-exposed control children (CON), matched closely in age, sex, and ethnicity were tested. For trials with visual feedback (WV), children with FASD were slower than CON children but were equally accurate. Although statistically significant group differences were not observed on most trials completed without visual feedback (WOV), accuracy of the FASD group on WOV trials was highly variable. Group differences in accuracy on WOV angles approached significance after accounting for performance on the WV angles, and children with FASD were significantly less accurate on an individual angle believed to be particularly sensitive to interhemispheric interaction. These results indicate that children with FASD are slower than CON children but equally accurate on basic visuomotor tasks. However, as task complexity and reliance on interhemispheric interaction increases, children with FASD demonstrate variable and inaccurate performance. Preliminary analyses suggest that inaccurate performance on the bimanual coordination task, and presumably impaired callosal functioning, may be related to the attention and problem solving impairments commonly reported in children with FASD. (JINS, 2004, 10, 536–548.)