Basic impairments in regulating the speed-accuracy tradeoff predict symptoms of attention-deficit/hyperactivity disorder.

Background: Attention-deficit/hyperactivity disorder (ADHD) is characterized by poor optimization of behavior in the face of changing demands. Theoretical accounts of ADHD have often focused on higher-order cognitive processes and typically assume that basic processes are unaffected. It is an open question whether this is indeed the case.

Method: We explored basic cognitive processing in 25 subjects with ADHD and 30 typically developing children and adolescents with a perceptual decision-making paradigm. We investigated whether individuals with ADHD were able to balance the speed and accuracy of decisions.

Results: We found impairments in the optimization of the speed-accuracy tradeoff. Furthermore, these impairments were directly related to the hyperactive and impulsive symptoms that characterize the ADHD-phenotype.

Conclusions: These data suggest that impairments in basic cognitive processing are central to the disorder. This calls into question conceptualizations of ADHD as a "higher-order" deficit, as such simple decision processes are at the core of almost every paradigm used in ADHD research.