Working memory control deficit in kindergarten ADHD children.

The present study tests the hypothesis that a working memory deficit is also found in children with attention deficit/hyperactivity disorder (ADHD) symptoms as young as 5 and is related to the control of interfering information. One group of 23 kindergarten children identified by the presence of ADHD symptoms and one group of 23 children matched for gender, age, and socioeconomic status were administered a visuospatial working memory task that required the selective recall of information. Children with ADHD symptoms performed more poorly than controls and were affected to a particularly high extent by intrusion errors (i.e., recalling of information initially encoded but that needed to be consequently suppressed during the task).