Abstract
A recent review of the Continuous Performance Task (CPT) as a research tool by Corkum and Siegel, Journal of Child Psychology and Psychiatry, 34, 1217-1239, 1993, is criticized for insufficient covering of the relevant literature, disregard of the question of differentiation among clinical groups, and inadequacy of explanations of Attention-Deficit-Hyperactivity Disorder (ADHD) in terms of arousal, activation, and effort. An attention-deficit in ADHD children cannot be inferred from poor performance on a CPT. Impaired performance is anything but specific to ADHD children and is caused by a host of variables among which "attention" probably plays a minor role.