The National Institute of Neurological Disorders and Stroke reports that six out of every 1,000 children are diagnosed with autism. This neurological condition is characterized by various impairments, such as difficulty communicating, social impairments, repetitive movements and altered behavioral patterns. Scientists are unsure as to the exact cause of autism; however, most agree environmental influences and genetics play a role in the development of this condition. One of the more interesting aspects of autism is the role of dopamine.
Role of Dopamine
Dopamine is a neurotransmitter found in the midbrain area, which is known as the substantia nigra. Dopamine is a chemical messenger responsible for determining how the brain processes emotional response to an external influence, bodily movements and the brain's ability to experience pain and pleasure, according to the University of Texas Addiction Science Research and Education Center.
Dopamine Levels in Autistic Individuals
Bryn Mawr College reports that autism is linked to an abnormality within the dopaminergic system in the brain, which then suggests individuals with autism have above average levels of brain dopamine. It has been found that abnormalities within the dopaminergic system lead to hyperactivity, which is a common symptom of autism. The University of California Berkeley School of Public Health reports research has found that damage to the mesolimbic dopamine system causes patterns and behaviors that match behaviors and symptoms of those with autism. In a study published in the August 2008 issue of the "Developmental Medicine and Child Neurology" journal, researchers from Kuopio University Unit of Child Neurology in Kuopio, Finland, found that children with autism had a lower count of serotonin transporter, or SERT, binding capacity through serotonergic nerve terminals rather than different levels of dopamine when compared to non-autistic children. This may suggest autism is more closely linked to an imbalance of serotonin rather than a dopamine imbalance; however, further studies are required to verify this finding.
Dopamine Related Treatment
Although there is no cure for autism, certain treatment programs can help reduce its symptoms. Macalester College, located in St. Paul, Minnesota, reports the use of dopamine antagonists, such as haloperidol, to treat autistic children with severe hyperactivity and other severe symptoms of autism. Research outlined by Macalester College found that treatment with dopamine antagonists successfully lowered dopamine levels in the brain, which resulted in a decrease in hyperactivity, stereotypes and negativism. There is also evidence that the use of dopamine antagonists helped increase learning ability.
Considerations
Although dopamine's effect on autistic individuals is promising within scientific communities, more research is needed to determine the exact role of dopamine in autism. Dopamine antagonist prescription medications may assist autistic children with severe hyperactivity; however, this type of treatment does come with side effects, which include tardive dyskinesia, a condition that causes uncontrollable facial tics and gestures.
References
- National Institute of Neurological Disorders and Stroke; Autism Fact Sheet; June 2011
- University of Texas Addiction Science Research and Education Center: Dopamine -- A Sample Neurotransmitter
- Bryn Mawr College; Neurological Perspectives on Autism; February 2008
- University of California Berkeley School of Public Health; Prefrontal Cortex, Dopamine, and Autism: Computational Connections; David Noelle; April 1, 2011
- "Developmental Medicine and Child Neurology"; Serotonin and Dopamine Transporter Binding in Children With Autism Determined by SPECT; I. Makkonen, et al.; August 2008
- Macalester College: Treatments
