Research on attention-deficit/hyperactivity disorder (ADHD), a highly prevalent and controversial condition, has, for the most part, been descriptive and atheoretical. The imperative to discover the genetic and environmental risk factors for ADHD is motivating the search for quantifiable intermediate constructs, termed endophenotypes. In this selective review, we conclude that such endophenotypes should be solidly grounded in the neurosciences. We propose that three such endophenotypes — a specific abnormality in reward-related circuitry that leads to shortened delay gradients, deficits in temporal processing that result in high intrasubject intertrial variability, and deficits in working memory — are most amenable to integrative collaborative approaches that aim to uncover the causes of ADHD.

Neuroscience of attention-deficit/hyperactivity disorder: the search for endophenotypes.

The neurobiological consequences of early stress and childhood maltreatment

The cerebellum and cognition.

• Recent clinical and research reports suggest that the cerebellum may contribute to the modulation of higher order behavior. This article presents a critical review of both earlier and more current clinical observations that raise this possibility, as well as a review of the salient laboratory data that appear to support this contention. It also summarizes the relevant anatomic work concerning the contributions to the cortico-pontocerebellar pathways from the higher order cerebral association areas, which have been implicated as partial anatomic substrates for this putative cerebellar role in higher function. Finally, it provides a framework for the understanding of this correlation, concludes with suggestions for future areas of investigation, and recommends that patients with cerebellar lesions be studied from a neurobehavioral point of view.

A. Maiti

Papers

Cerebellar pathways to ventral midbrain and nigra.