The relationship between measures of cognitive attention and behavioral ratings of attention in typically developing children.

In the present study, we explored the relation between performance on cognitive measures of attention (selection, sustained, and control) and behavioral ratings of inattention and hyperactivity in a sample of typically developing children aged 3 to 7 years. We also examined the influence of chronological age and IQ on both task performance and behavior ratings. Four well-documented attention paradigms were employed, the Visearch (single-target search) task as a measure of selective attention, the Continuous Performance Test (CPT) as a measure of sustained attention, the Day-Night task as a measure of response inhibition, and the Visearch (dual-target search) task as a measure of inhibitory control.

Differential behavioral and neurochemical effects of cocaine after early exposure to methylphenidate in an animal model of attention deficit hyperactivity disorder.

We used a putative animal model of attention deficit hyperactivity disorder (ADHD), the SHR rat, to examine the effects of repeated exposure to methylphenidate (MPH; Ritalin) during the pubertal period on cocaine-induced conditioned place preference and dopamine (DA) levels in the nucleus accumbens (NAc) in adulthood. Our results indicate that early exposure to methylphenidate diminishes sensitivity to the incentive properties of cocaine in adulthood, but it does so without altering the response of the mesolimbic dopamine system.