Timing accuracy and variability in children with prenatal exposure to alcohol

Background: Prenatal exposure to alcohol (prenatal alcohol exposure) is associated with gross and fine motor skill dysfunction. The present study examined performance on two types of timing tasks to determine the extent to which prenatal alcohol exposure affects perception, movement planning, and movement execution during tasks that require temporal processing. Methods: Fourteen children with confirmed heavy prenatal alcohol exposure and 22 control children (aged 5-10 years) completed two timing tasks: a coincident-anticipation timing task that primarily assessed central processing, and a movement-speed timing task that evaluated the motor component of temporal processing. Absolute error, signed error, and variability of the participant's signed error were the dependent variables. Results: For both timing tasks, children with prenatal alcohol exposure were significantly less accurate and more variable than control children, indicating that both the sensory-perceptual and motor components of temporal processing were disrupted in alcohol-exposed children. Conclusions: Alcohol-exposed children had difficulty producing accurate and consistent motor responses when intercepting a moving target or moving through a spatial target in a specified amount of time. Disruptions in these motor timing behaviors may be indicative of alcohol-related cerebellar or basal ganglia damage.