Covert orienting of visual spatial attention in attention deficit hyperactivity disorder: Does comorbidity make a difference?

Attentional performance in children with attention deficit hyperactivity di sorder (ADHD) with and without comorbid disorders was examined using the Co vert Orienting of Visuospatial Attention Task (COVAT) and the Continuous Pe rformance Task (CPT). The relationship between these two tasks was also exa mined. The results showed no overall differences on the attention tasks bet ween children with ADHD alone and those with ADHD pills other disorders. Co mpared to non-ADHD control children, children with ADHD showed a deficit in the disengage operation of covert visuospatial attention, suggesting a dif ficulty in the endogenous mode of orienting. The ADHD children also showed a general performance deficit on the CPT. Although there was a general slow ing on both attention tasks in the ADHD group, there was no relationship be tween invalid cue effect sizes on the COVAT and the CPT measures. These res ults indicate that these two attention tasks may be tapping both similar an d independent underlying cognitive processes in ADHD. (C) 1999 National Aca demy of Neuropsychology. Published by Elsevier Science Ltd.