Researchers aren't entirely sure what causes Asperger's syndrome, a developmental disorder that causes social and communication deficits. However, scientists believe that a combination of genetics and malfunctions in the brain's communication system, such as an overproduction of certain neurotransmitters like dopamine, are involved in the etiology of this disorder.
About Asperger's Syndrome
Asperger's syndrome, also referred to as Asperger disorder, is a type of autism spectrum disorder. Autism spectrum disorders are characterized by impaired language and communication skills and repetitive or restrictive thoughts and behaviors, according to the National Institute of Neurological Disorders and Stroke. A specific gene linked to Asperger's hasn't yet been identified. Researchers have found that people with Asperger's syndrome have abnormalities in the dopamine system, a group of midbrain cells involved with the brain's "reward system"
Dopamine and the Reward System
Dopamine is a catecholamines neurotransmitter, or brain chemical involved in communication between neurons. Catecholamines are a part of the "fight-or-flight" instinct and also stimulate pleasure pathways in the brain. Elevated levels of dopamine can cause an increase in pleasure-seeking activities, such as the repetitive behaviors common to people with Asperger's syndrome.
For example, many children with Asperger's obsessively engage in computer and video games. Brain scans of children with Asperger's syndrome while they are playing video games indicate that their brains release dopamine in the same way that nicotine and narcotics stimulate the release of dopamine and pleasurable feelings, according to mental health counselor George T. Lynn in his book "The Asperger Plus Child." However, over long periods dopamine levels subsequently decrease, causing an increase in irritability and fatigue, which creates difficulties in behavior and performing basic tasks.
Clinical Evidence
One clinical study has confirmed dopamine's involvement in Asperger's syndrome. This study, published in the April 2004 issue of the journal "NeuroReport," a professional publication dedicated to neuroscience research, found increases in presynaptic dopamine in the brains of eight study participants with Asperger's syndrome. Another study, published in the May 2002 issue of the journal "Progress in Neurobiology," demonstrated a link between dopamine's involvement in disorders involving attention deficits and cognitive impairment. Further studies are necessary to fully confirm the role of dopamine in the development of autism spectrum disorders like Asperger's syndrome.
Considerations
Certain medications, known as neuroleptics or antipsychotics, may be useful for treating children with Asperger's syndrome. These medications may help certain symptoms of Asperger's syndrome, such as anxiety, sleep disturbances and social withdrawal, as they focus on blocking dopamine receptors in the brain, according to Linda J. Baker and Lawrence A. Welkowitz in their book "Asperger's Syndrome." Consult your child's doctor to discuss possible medications and other treatment options.
References
- National Institute of Neurological Disorders and Stroke: Asperger Syndrome
- "The Asperger Plus Child"; George T. Lynn, M.A.; 2007
- "NeuroReport"; Increased Presynaptic Dopamine Function in Asperger Syndrome; T. Nieminen-von Wendt, et al.; April 2004
- "Progress in Neurobiology"; Dopamine and the Regulation of Cognition and Attention; A. Nieoullon; May 2002
- "Asperger's Syndrome"; Linda J. Baker, et al.; 2005
