Abstract
There is increasing evidence that timing deficits represent a primary cause of key symptoms in ADHD. However, results in experiments on timing may vary with different methods of assessing timing competencies. The present study directly compared two central paradigms, namely, prospective and retrospective time estimation in children with (n = 30) and without (n = 29) ADHD. In both conditions, durations were estimated considerably longer by children with ADHD. Children with ADHD significantly overestimated the real duration of the task compared to children without ADHD in the retrospective but not in the prospective condition. In general, prospective estimates were more accurate than retrospective ones. The findings corroborate the essential role that timing deficits and a faster internal clock play in ADHD. Furthermore, the results demonstrate the importance of careful differentiation between prospective and retrospective time estimation.