Attention Deficit Hyperactivity Disorder (ADHD)
Although Attention Deficit Hyperactivity (ADHD) is a disorder that is usually first diagnosed in and associated with childhood, approximately two thirds of those that meet criteria for the condition in childhood continue to experience symptoms into adulthood. Also, ADHD is a condition that has increasingly become conceptualised as neuropsychological (i.e., brain-based) in nature. Several findings from the scientific literature support this. For example, there is evidence that noradrenergic neurotransmission and right hemisphere brain functioning is anomalous in ADHD. Frontal lobe / systems dysfunction is also implicated in ADHD.
Attention in ADHD
Attention is an integral component of all higher level cognitive functioning. However, there is often confusion about the various aspects of human attention. Not all aspects of attention are affected in ADHD. In fact, some aspects of attention are more significantly impaired in other conditions such as Specific Learning Disorder. The components of attention that are more often implicated in ADHD are sustained and focussed attention. Auditory attention span, on the other hand, tends to be relatively well preserved. A neuropsychological assessment can determine the relative functioning of the various components of attention to inform a diagnosis or practical recommendations for someone suspected of having ADHD.
Executive Functioning in ADHD
Although some aspects of attention functioning tend to be impaired in ADHD, a more significant and reliable finding in neuropsychological studies on individuals with ADHD is that aspects of executive functioning are affected. The executive constructs of response inhibition, planning and organisation are implicated in ADHD. Impairments in these areas most significantly contribute to the functional limitations that those with ADHD experience. Poor executive functioning can lead to difficulties completing studies or maintaining employment. In extreme cases there may also be implications on one’s capacity to operate heavy machinery or drive a motor vehicle.