Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood neuropsychiatric disorders, and it often persists into adulthood. The psychopathology of this disorder is marked by developmentally inappropriate and pervasive expressions of inattention, overactivity, and impulsiveness. ADHD is also associated with functional impairments across multiple academic and social domains and is commonly accompanied by a range of externalizing and internalizing disorders [Biederman and Faraone, 2006]. Given the associated burden to society, family and the individual child, understanding the causes of ADHD and developing new and more effective treatments targeting these underlying causes is an important goal for neuroscience research.
Although neuroimaging studies clearly point to a neurobiological basis for the disorder, the pathophysiological mechanisms of ADHD and the specific nature of the atypical brain development underlying it remain poorly understood. Recently, in concordance with emerging concepts in other neuropsychiatric disorders such as schizophrenia and autism, a change in perspective in etiological models of ADHD has occurred. These models shift the focus of the assumed pathology from regional brain abnormalities to dysfunctions in distributed network organization [Sergeant et al., 2006]. While the assessment of functional segregation in the human brain, i.e., the localization of regionally specific functions, has been the predominant concept in imaging neuroscience for many years, the pathophysiology of neuropsychiatric disorders is now being increasingly treated from a systems perspective in which function emerges from an interaction of regionally specialized elements. As a result, the analysis of brain connectivity has become more and more critical.
For more articles like this please sign up for our eTips by liking us on Facebook and giving us your email for our Newsletter.