Autism overview: Difference between revisions
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Despite extensive investigation, how autism occurs is not well understood. Its mechanism can be divided into two areas: the [[pathophysiology]] of brain structures and processes associated with autism, and the [[neuropsychological]] linkages between brain structures and behaviors.<ref name=Penn>{{cite journal |author= Penn HE |title= Neurobiological correlates of autism: a review of recent research |journal= Child Neuropsychol |date=2006 |volume=12 |issue=1 |pages=57–79 |doi=10.1080/09297040500253546 |pmid=16484102}}</ref> The behaviors appear to have multiple pathophysiologies. | Despite extensive investigation, how autism occurs is not well understood. Its mechanism can be divided into two areas: the [[pathophysiology]] of brain structures and processes associated with autism, and the [[neuropsychological]] linkages between brain structures and behaviors.<ref name=Penn>{{cite journal |author= Penn HE |title= Neurobiological correlates of autism: a review of recent research |journal= Child Neuropsychol |date=2006 |volume=12 |issue=1 |pages=57–79 |doi=10.1080/09297040500253546 |pmid=16484102}}</ref> The behaviors appear to have multiple pathophysiologies. | ||
==Causes== | |||
[[Autism]] and [[autism spectrum disorder]]s are complex [[neurodevelopmental disorder]]s. Many ''causes of autism'' have been proposed, but its [[Etiology|theory of causation]] is still incomplete.<ref name=Trottier>{{cite journal|author=Trottier G, Srivastava L, Walker CD|title=Etiology of infantile autism: a review of recent advances in genetic and neurobiological research|journal=J Psychiatry Neurosci|date=1999|volume=24|issue=2|pages=103–115|pmid=10212552|url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?pubmedid=10212552|accessdate=2007-07-16}}</ref> [[Heritability]] contributes about 90% of the risk of a child developing autism, but the [[Heritability of autism|genetics of autism]] are complex and typically it is unclear which genes are responsible.<ref name=Freitag>{{cite journal|author=Freitag CM|title=The genetics of autistic disorders and its clinical relevance: a review of the literature|journal=Mol Psychiatry|volume=12|issue=1|pages=2–22|date=2007|doi=10.1038/sj.mp.4001896|pmid=17033636|url=http://www.nature.com/mp/journal/v12/n1/full/4001896a.html}}</ref> In rare cases, autism is strongly associated with [[Teratology|agents that cause birth defects]].<ref name=Arndt>{{cite journal|journal=Int J Dev Neurosci|date=2005|volume=23|issue=2–3|pages=189–99|title=The teratology of autism|author=Arndt TL, Stodgell CJ, Rodier PM|doi=10.1016/j.ijdevneu.2004.11.001|pmid=15749245}}</ref> Many other causes have been proposed, such as exposure of children to vaccines; these proposals are [[Controversies in autism|controversial]] and the vaccine hypotheses have no [[Evidence-based medicine|convincing scientific evidence]].<ref name=Rutter>{{cite journal|author=[[Michael Rutter|Rutter M]]|title=Incidence of autism spectrum disorders: changes over time and their meaning|journal=Acta Paediatr|volume=94|issue=1|date=2005|pages=2–15|pmid=15858952}}</ref> | |||
==References== | ==References== | ||
Revision as of 16:50, 11 February 2013
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Autism Microchapters |
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Treatment |
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Case Studies |
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Autism overview On the Web |
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American Roentgen Ray Society Images of Autism overview |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Autism is a brain development disorder that impairs social interaction and communication, and causes restricted and repetitive behavior, all starting before a child is three years old. This set of signs distinguishes autism from milder autism spectrum disorders (ASD) such as Asperger syndrome. Autism has a strong genetic basis, although the genetics of autism are complex and it is unclear whether ASD is explained more by multigene interactions or by rare mutations. In rare cases, autism is strongly associated with agents that cause birth defects. Other proposed causes, such as childhood vaccines, are controversial and the vaccine hypotheses lack convincing scientific evidence. Most recent reviews estimate a prevalence of 100- 200 cases per 100,000 people for autism, and about 600 per 100,000 for ASD, with ASD averaging a 4.3:1 male-to-female ratio. The number of people known to have autism has increased dramatically since the 1980s, at least partly due to changes in diagnostic practice; the question of whether actual prevalence has increased is unresolved. Autism affects many parts of the brain; how this occurs is poorly understood. Parents usually notice signs in the first two years of their child's life. Early behavioral or cognitive intervention can help children gain self-care, social, and communication skills. There is no cure. Few children with autism live independently after reaching adulthood, but some become successful, and an autistic culture has developed, with some seeking a cure and others believing that autism is a condition rather than a disorder.
Pathophysiology
Despite extensive investigation, how autism occurs is not well understood. Its mechanism can be divided into two areas: the pathophysiology of brain structures and processes associated with autism, and the neuropsychological linkages between brain structures and behaviors.[1] The behaviors appear to have multiple pathophysiologies.
Causes
Autism and autism spectrum disorders are complex neurodevelopmental disorders. Many causes of autism have been proposed, but its theory of causation is still incomplete.[2] Heritability contributes about 90% of the risk of a child developing autism, but the genetics of autism are complex and typically it is unclear which genes are responsible.[3] In rare cases, autism is strongly associated with agents that cause birth defects.[4] Many other causes have been proposed, such as exposure of children to vaccines; these proposals are controversial and the vaccine hypotheses have no convincing scientific evidence.[5]
References
- ↑ Penn HE (2006). "Neurobiological correlates of autism: a review of recent research". Child Neuropsychol. 12 (1): 57–79. doi:10.1080/09297040500253546. PMID 16484102.
- ↑ Trottier G, Srivastava L, Walker CD (1999). "Etiology of infantile autism: a review of recent advances in genetic and neurobiological research". J Psychiatry Neurosci. 24 (2): 103–115. PMID 10212552. Retrieved 2007-07-16.
- ↑ Freitag CM (2007). "The genetics of autistic disorders and its clinical relevance: a review of the literature". Mol Psychiatry. 12 (1): 2–22. doi:10.1038/sj.mp.4001896. PMID 17033636.
- ↑ Arndt TL, Stodgell CJ, Rodier PM (2005). "The teratology of autism". Int J Dev Neurosci. 23 (2–3): 189–99. doi:10.1016/j.ijdevneu.2004.11.001. PMID 15749245.
- ↑ Rutter M (2005). "Incidence of autism spectrum disorders: changes over time and their meaning". Acta Paediatr. 94 (1): 2–15. PMID 15858952.