Metabolic alterations in the prefrontal and cingulate cortices are relatedto behavioral deficits in a rodent model of attention-deficit hyperactivity disorder

Rats with a deficit in selective attention accompanied by impulsivity can b e identified using a five-choice serial reaction time task (5-CSRT) and hav e been proposed to represent a rodent model of attention-deficit hyperactiv ity disorder (AND). The aim of the present study was to investigate which b rain areas are important for visuospatial attention and to test the specifi c hypothesis that dysfunction of the frontal cortex is related to the behav ioral deficits observed in poorly performing rats. Therefore, [C-14]deoxygl ucose (DG) uptake, an index of brain metabolic activity, was measured durin g the performance of a 5-CSRT task in two populations of rats (poorly and w ell-performing rats) to study the relationships between the regional brain activity and behavioral output. While performing a 5-CSRT task, poorly perf orming rats exhibited lower DG uptake in the cingulate and ventrolateral or bital cortices than did well-performing rats,. Moreover, there was a positi ve correlation between choice accuracy and DG uptake in several areas, espe cially in the frontal and parietal regions, whereas there was an inverse co rrelation between the percentage of premature responses and DG uptake in th e ventrolateral orbital and cingulate cortices. These results, which demons trated that the poorly performing rats exhibited metabolic dysfunction in t he cingulate and prefrontal cortices, provide a basis for the face validity of the rodent model of ADHD. Moreover, they suggest that the neural networ k of attention in rats is remarkably analogous to that described in primate s.