Attention Deficit Hyperactivity Disorder

Abstract

Over the last two decades, there have been numerous technical and methodological advances available to clinicians and researchers to better understand attention deficit hyperactivity disorder (ADHD) and its etiology. Despite the growing body of literature investigating the disorder's pathophysiology, ADHD remains a complex psychiatric disorder to characterize. This chapter will briefly review the literature on ADHD, with a focus on its history, the current genetic insights, neurophysiologic theories, and the use of neuroimaging to further understand the etiology. We address some of the major concerns that remain unclear about ADHD, including subtype instability, heterogeneity, and the underlying neural correlates that define the disorder. We highlight that the field of ADHD is rapidly evolving; the descriptions provided here will hopefully provide a sturdy foundation for which to build and improve our understanding of the disorder.

Neural correlates of visuospatial working memory in attention-deficit/hyperactivity disorder and healthy controls

“…3). Regions of spatial span-related activation are consistent with previous findings in a small sample of typically developing children, using a similar task (Klingberg et al, 2002), and largely coincide with activation patterns associated with executive control (Gilbert et al, 2006;Dosenbach et al, 2007;Matthews et al, 2014), an important component of working memory (Baddeley, 2003). Considering our large sample size, broad age range and even distribution of gender, we here provide a robust estimate of spatial span-related brain activation patterns in children, adolescents and young adults, with and without ADHD.…”

Attention-deficit hyperactivity disorder: a clinical review of the concept, diagnosis and management

“…Also known as 'hyperkinetic disorders' (WHO, 1992), there are few descriptions of syndromes similar to ADHD in the ancient literature, and accounts of analogous conditions only appear in European literature from the late 1700s and in the United States from the early 1800s (Matthews et al 2014). This is a relatively late appearance compared with other conditions, such as depression and psychosis, which feature commonly in early medical literatures (Kelly, 2016).…”

Neurobiology of Adult ADHD: Emerging Evidence for Network Dysfunctions

“…Dimensions of potential variability within the broad ADHD classification include comorbid diagnoses, gender, age, and predominate symptom presentation. 8,10,13 These areas of variability, combined with other complicating factors (e.g. treated versus medication naïve) have added to the complexity of elucidating this disorder.…”

“…Clinical variability may indicate the possibility of multiple developmental pathways. 13 The flawed conception that ADHD is only a disorder of children lingers, and may contribute to the under recognition of this disorder in adults. 10,12 Studies indicate that only a minority of adults with ADHD are currently receiving treatment.…”

“…[8][9][10][11][12][13] However, research began to gain traction in the 1990s demonstrating a significant proportion of children with ADHD continued to meet diagnostic criteria into adulthood although clinical presentation may change.…”