Neuropsychological functioning in children with Tourette syndrome with and without attention-deficit/hyperactivity disorder

J Am Acad Child Adolesc Psychiatry. 2010 Nov;49(11):1155-64. doi: 10.1016/j.jaac.2010.08.008.

Abstract

Objective: Neuropsychological functioning in children with Tourette syndrome (TS) has been characterized by subtle deficits in response inhibition, visual-motor integration, and fine-motor coordination. The association of these deficits with the tics of the TS versus co-occurring attention-deficit/hyperactivity disorder (ADHD) has not been well understood because of small sample sizes and lack of adequate control conditions. We examined neuropsychological functioning in relatively large and well-characterized samples of children categorized as TS, TS-plus-ADHD, ADHD, and unaffected controls.

Method: A total of 56 children with TS-only, 45 with TS-plus-ADHD, 64 with ADHD, and 71 healthy community control subjects were assessed on a battery of neuropsychological measures including the Connors' Continuous Performance Test (CPT), the Stroop Color-Word Interference Test (Stroop), the Beery Visual-Motor Integration Test (VMI), and the Purdue Pegboard Test.

Results: There were no differences between children with TS-only and unaffected controls on the measures of response inhibition and visual-motor integration. Boys with TS-only but not girls with TS-only were impaired in the dominant hand Purdue performance. Children with ADHD were impaired on all study measures. Children with TS-plus-ADHD revealed no deficits on the Stroop, VMI, and Purdue tests but were impaired on the sustained attention portion of the CPT.

Conclusions: These results indicate that co-occurring ADHD may be responsible for the neuropsychological deficits, or at least those assessed in the present study, in children with TS. Explanations in terms of neurobiological mechanisms of co-occurring TS and ADHD, as well as possible compensatory mechanisms in children with TS, are discussed.

Publication types

  • Clinical Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Attention Deficit Disorder with Hyperactivity* / complications
  • Attention Deficit Disorder with Hyperactivity* / diagnosis
  • Attention Deficit Disorder with Hyperactivity* / psychology
  • Child
  • Female
  • Humans
  • Male
  • Neuropsychological Tests*
  • Psychomotor Agitation
  • Psychomotor Performance
  • Reactive Inhibition
  • Severity of Illness Index
  • Tourette Syndrome* / complications
  • Tourette Syndrome* / diagnosis
  • Tourette Syndrome* / physiopathology
  • Tourette Syndrome* / psychology