 Studies conducted in 1997 tested the relationship between ADHD and deficiency in sense of time perception; predicting and evaluating the effects of interval duration, distraction, and stimulant medication (methylphenidate (MPH) on the reproductions of temporal durations in children with ADHD.Results showed that time perception is impaired in children with ADHD and the capacity to accurately reproduce time intervals in ADHD children does not seem to improve with administration of stimulant medication.Work from 2003 used time reproduction tasks to compare time perception in children with and without ADHD.