Attention Deficit Disorder: Brain Functioning and AD/HD
This paper will explore current research concerning AD/HD and brain function, including attention and arousal, and the involvement of the dopamine transporter, prefrontal cortex, limbic system, and basal ganglia in AD/HD symptomology.
Most of the studies pertaining to brain structures and ADHD have dealt with analysis of the frontal lobe. Dysfunction of the frontal lobe (other than that associated with ADHD) can and does manifest itself in symptoms that are closely associated with ADHD. Those symptoms are affect perception and regulation of arousal (Stefanatos & Wasserstein, 2001). ...view middle of the document...
AD/HD is one of the most puzzling and pervasive disorders of childhood, and, unfortunately, typically persists into adulthood. Estimates are that AD/HD affects between 5 and 15% of the population (Rie & Rie, 1980). This paper will explore current research concerning AD/HD and brain function, including attention and arousal, and the involvement of the dopamine transporter, prefrontal cortex, limbic system, and basal ganglia in AD/HD symptomology.
ATTENTION DEFICIT DISORDER :
Attention Deficit Disorder (ADD), as defined by DSM IV guidelines is characterized by a persistent pattern of inattention, hyperactivity, and impulsiveness, though it can present with or without hyperactivity (APA, 1994). The core symptoms -- impulsivity, inattention and motor restlessness -- are reported universally by patients and clinicians alike. However, because attentional difficulties are encountered frequently together with other psychiatric disorders and brain diseases, under or over diagnosis of AD/HD is not uncommon. Attentional disorders impose a great burden on the individual, strongly disrupt family functioning, and drain an enormous amount of talent and energy from society. The effects discourage and demoralize those who experience attention deficit disorder, frequently leading them away from productive activity and into antisocial lifestyles, drug abuse, and criminal behaviors (Castellanos,1997). Continued advances in the understanding and treatment of attentional and related disorders will likely produce significant gains in every social domain.
Barkley reports on a theoretical model that links attentional inhibitions to four key executive neuro-psychological abilities: (a) working memory, (b) self-regulation of affect-motivation-arousal, (c) internalization of speech, and (d) reconstitution (behavioral analysis and synthesis) (Barkley, 1997). Extended to AD/HD, the model shows the association between AD/D and impairments in these four executive abilities and the motor controls they effect.
Pharmacological treatment, primarily with stimulants and tricyclic antidepressants, has been found effective in the treatment of AD/HD (Barkley, 1990). Recently, neurofeedback has been reported to be effective in the treatment of attentional disorders. Of major clinical importance is the fact that AD/HD appears to persist well after treatment ends. Unfortunately, the medication and neurofeedback treatments are sometimes considered mutually exclusive by their respective proponents in the health profession.
BRAIN FUNCTIONING AND AD/HD:
Research into brain abnormalities in AD/HD individuals has centered on four structural areas: the frontal lobe, the parietal lobe, the temporal lobe and the corpus collosum. Also, there has been some. A summary of a number of independent studies was done by Rapoport (2001) concerning research into brain size and AD/HD. These studies indicated that AD/HD individuals had a smaller overall brain volume...