Sustained and focused attention deficits in adult ADHD.

OBJECTIVE To examine the specificity of deficits in focused attention and sustained attention in adults with ADHD and to evaluate the effect of comorbidity. METHOD Twenty-eight adults with ADHD without comorbidity were compared with 28 ADHD outpatients with comorbidity. Two control groups were used: 68 adults referred for ADHD but with another psychopathology rather than ADHD (non-ADHD) and 28 healthy controls. All participants completed attention tests of the Amsterdam Neuropsychological Tasks program. RESULTS Both ADHD groups demonstrated a sustained attention deficit relative to the control groups, as indicated by a disproportionate deterioration of speed fluctuation with time-on-task reflecting temporal lapses in attention. Only the ADHD+ group showed focused attention deficits in that they were less able to ignore irrelevant information. CONCLUSION These findings show that adults with ADHD have specific deficits in sustained attention. Additional deficits in focused attention are confined to outpatients with ADHD and comorbidity.