[Attentional impairment in children with attention deficit and hyperactivity disorder].

Background: Attention-deficit hyperactivity disorder (ADHD) is a heterogeneous disorder currently defined by clinical history and behavioral report of impairment. The Attention Network test (ANT) gives measures of different aspects of the complex process of attention.

Aims: We ask if children with Attention Deficit Hyperactivity Disorder (ADHD) will show a characteristic pattern of deficits on this test.

Methods: The sample included 40 children (M=9 years) who performed the "Attention network test". Children with an ADHD diagnosis (N=20) were compared to a control group (N=20).

Results: The group of children with ADHD showed slower reaction times in all conditions (mean RT=866 ms; SD=234,063). Children with ADHD showed a significant impairment in their executive control system compared to healthy subjects, with slower reaction times in incongruent conditions and lower accuracy scores (RT=1064 ms; F(1.38) p=0.02). Our results showed that spatial orienting and alerting in ADHD was no different than controls (p=0,68). ADHD group showed a greater variable response (p=0,0001).

Conclusion: The present study showed that impairment in executive control system and variability measures are the characteristic pattern of deficits in children with ADHD.