Autistic behavior

Mutations in the gene for adenylosuccinate lyase (ASL), inherited as an autosomal recessive disorder in purine metabolism, are associated with severe mental retardation and autistic behavior, but apparently not self-mutilation [10, 11]. This enzyme catalyzes two distinct reactions in the de novo biosynthesis of purines the cleavages of adenylosuccinate (S-Ado) and succinylaminoimidazole carboxamide ribotide (SAICAR), both of which accumulate in plasma, urine and cerebrospinal fluid of affected individuals [12]. Measurements of these metabolites in urine... 

The report of 5-HTTLPR allelic association with severity in specific domains of autistic behavior (Tordjman et ah, 2001) raises two general issues. First, the use of overall response as the end point in pharmaco-genetic studies may not be sufficiently specific to identify an association between response and genotype. The... 

Willemsen-Swinkels, S.H.N., Buitelaar, J.K., Nijhof, G., and Van Engeland, H. (1995a) Failure of naltrexone hydrochloride to reduce self-injurious and autistic behavior in mentally retarded adults. Double-blind placebo-controlled studies. Arch Gen Psychiatry 52 766-773. 

Zingarelli, G., Ellman, G., Horn, A., Wymore, M., Heidorn, S., and Chicz DeMet, A. (1992) Clinical effects of naltrexone on autistic behavior. Am J Ment Retard 97 57-63. 

Kurita, H. and Miyake, Y. (1990) The reliability and validity of the Tokyo Autistic Behavior Scale. Jpn J Psychiatry Neurol, 44, 25-32. 

Tachimori, H., Takahashi, M., Osada, H., Watanabe, Y., Naganuma, Y., Setoya, Y., Kubota, Y., Kato, S., and Kurita, H. (2000) The utility of Tokyo Autistic Behavior Scale (TABS) as a supplemen-taty scale fot diagnosis of pervasive developmental disorders, [in Japanese]./p J Clin Psychiatry 29 529-536. 

Green (1989) provided a comprehensive review showing that virtually every childhood disorder can be produced by environmental trauma and stress. The whole range of childhood disorders, from autistic behavior... 

A child with severe epilepsy, autistic behavior, and developmental delay has characteristics of a condition known as Angelman s syndrome. Because of the syndromic nature of the disorder and the developmental delay, a karyotype is performed that shows a missing band on one chromosome 15. Which of the following best describes this abnormality ... 

Williams RS, Hauser SL, Purpura DP, DeLong GR, Swisher CN (1980) Autism and mental retardation neuropathologic studies performed in four retarded persons with autistic behavior. Arch Neurology 37 749-753. 

Hermelin B, Frith U (1991) Psychological studies of childhood autism can autistic children make sense of what they hear Focus on Autistic Behavior 6 6-13. 

With these tools in hand, further definition of a cognitive dynamics analysis and its insights into the normative flow of information will provide a window into the cognitive dynamics of ASD. The plausible conclusion that autistic behaviors can emerge from non-autistic brains will be briefly explored. 

Although a wide range of drugs are used to ameliorate symptoms of autistic behavior, currently there is no effective treatment. We discuss novel treatments such as use of cholinesterase inhibitors and nicotinic receptor antagonists as intervention therapies for treatment of the cognitive and non-cognitive changes in the autistic spectrum disorders. 

In the final chapter, an expert pharmacologist. Dr. Terrell Gibbs presents a comprehensive review of pharmacotherapies in autism. He details their results from clinical trials, their effectiveness, and their role in the treatment of autistic behaviors. Special emphasis is given to the atypical antipsychotic drug risperidone that is frequently effective for ameliorating symptoms of irritability, hyperactivity, social withdrawal, and stereotypic, repetitive behavior in autism. 

A 6-year-old boy visits his physician because his parents have noticed autistic behavior and speech problems. The mother s family does have a history of mental retardation. Therefore, the physician suggested a genetic screen of the fragile X mental retardation 1 (FMRl) gene for fragile X syndrome. Polymerase chain reaction (PCR) revealed borderline fragile X syndrome. 

The portrayal of autistic behavior in films and books is useful to increase public awareness, but such portrayals are usually of mild cases. Here are some elements of an actual case of severe autism in a Nigerian boy 13 years of age 48... 

Indeed, given the complexity of autistic behavior, it s reasonable to assume that more than a single cause might be involved in different individuals genetic factors, prenatal impacts, postnatal toxins, or some combination of these causes. The question before us here is to what degree might the clinical entities called autism spectrum disorder (broad autism) and its severe form (narrow autism) involve prenatal impact on the developing embryo or fetus ... 

The Bettelheim interlude in American psychiatry illustrates how dogma in science can be dangerous, in this case producing a public condemnation of the parents of autistic children, parents who suffered enormous guilt following the accusations that they were to blame for the autistic behavior manifested in their children. The best that can be said about Bettelheim is that his dogma was essentially the dogma of his contemporary psychoanalytic psychiatrists—so maybe they should all be blamed for the misery they caused. 

MRI studies of adolescent autistic children show increases in thickness of the cerebral cortex (gray matter) in specific areas of the brain coupled with decreases in thickness of fiber tracts (white matter) leading in and out of those and other areas.63 This provokes the idea that a combination of developmentally enlarged cortex and reduced white matter may be the structural basis of autism. But it s also possible that the anatomical differences may be a consequence of autistic behavior rather than a basis, since the development of the brain continues throughout childhood. 

Can autistic behavior be related to specifics about nerve cells A neuron fires nerve impulses either spontaneously or as a result of input of nerve impulses from other neurons. Mirror neurons are those in the brain cortex of animals (and presumably also in humans) that fire both when movements of the body occur in the animal and when the animal observes movements in another animal.64 Several regions of the animal cortex apparently contain mirror neurons, and in the analogous regions in human brain cortex of autistic patients, neuron activity is evidently depressed. This has led to the idea that autism is caused by a lack of mirror neurons, the deficiency leading to deficits in social skills, imitation, empathy, and so on. The idea is speculative. Other... 

It is thought that the causes for autistic behavior are a combination of genetic makeup and environmental factors. Although the right genes must be present, not all children with these genes develop autism. Speculate on possible environmental causes. 

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