[Neuropsychological performance in ADHD and tic-disorders: a prospective 1-year follow-up]

Inhibitory deficits in the brain play a major role in the pathophysiology of ADHD and tic disorders. Impairment of executive functions (EF) may be directly linked to these abnormalities. Hence, parallel to an amelioration of symptomatology in ADHD and in tic disorders a decline of EF impairment should be observed. This phenomenon would indirectly suggest that there exist inhibitory deficits in these disorders. Age and IQ matched samples of boys one with ADHD (n = 15; age: M = 128 months SD = 16, IQ: M = 101 SD = 11), the other with tic disorders (n = 14; age: M = 132 months SD = 16; IQ: M = 101 SD = 10) have been compared with a group of controls (n = 23; age: M = 131 months SD = 13; IQ: M = 108 SD = 7). Reexamination has been performed after about one year. In ADHD EF deficits found at the beginning were decreased at the second testing after about one year when symptomatology had ameliorated. The boys with tic disorders revealed no differences compared to controls and no changes over time. The reduction of EF deficits with time in boys with ADHD is best explained by neuronal maturational processes, which are very intensive in the children with ADHD of this age.