Focusing on Those Who Cannot Focus

Abstract

The neurological differences present in the brains of people with ADHD have been extensively studied in the past 30 years using neuroimaging techniques such as functional magnetic resonance imaging (fMRI), among others. After going through the history of ADHD research, this paper reviews a wide range of research conducted using these two techniques and uses their findings to attempt to persuade skeptics that ADHD is not simply ‘people being lazy’—it is a real, neurologically differentiated disorder involving functional deficiencies in multiple specific brain regions. Differences in neural activation rates in the ventral striatum and ventral anterior thalamus greatly hinder the reward-processing capabilities of individuals with ADHD, making it more difficult for them to make wise decisions. Lower frontal striatal network activation in ADHD brains hinders response-inhibition capabilities. Methodological concerns involving the differences between selective attention and response inhibition are also addressed. Activation differences in the left inferior prefrontal cortex, cerebellum, and left inferior parietal lobe adversely impact ADHD individuals’ ability to accurately judge timing. Heightened activation in the precuneus and posterior cingulate cortex leads to issues with the brain’s default mode network in ADHD populations. Lowered activation in the frontal parietal, lateral prefrontal, temporal, striatum, and posterior parietal regions of the brain are associated with decreased working memory capabilities, the possible source of ADHD people’s characteristic scatterbrained tendencies. There is evidence to suggest that ADHD has a genetic component, specifically involving the DAT-1 genotype. In conclusion, people with ADHD are not simply ‘being lazy’—they are often trying their best to cope with neurological differences that make life more difficult for them than for those without the disorder.