This page has moved. Click here to view.

 

Idiot Savant, Autism and Autistic Disorder

Autistic disorder is characterized by sustained impairments in reciprocal social interactions, communication deviance, and restricted, stereotypical behavioral patterns. According to DSM-IV, abnormal functioning in the above areas must be present by age 3 years. More than two thirds of autistic persons function on a idiot savant and autism, atism, sevant, facilitated communication, autistic, atistic

EPIDEMIOLOGY

Prevalence

Most of the epidemiological surveys have found rates of 4 to 5 out of 10,000. However, recent studies have found higher rates, which may be attributed to more thorough case ascertainment, more

Sex ratio

The higher incidence of autism in boys than in girls has been well documented, with ratios of 2.6 to 1 common and ratios up to 4 to 1 found in some studies. Girls are often more

ETIOLOGY

Biological theories

Early clues to the biological basis of autism included the high rate of associated mental retardation, the 4 to 1 male-female ratio, the increased incidence of seizure disorders, and the recognition that medical and genetic conditions such as congenital rubella and untreated phenylketonuria could be associated with the syndrome. It is now believed that

Genetic factors

Results of family and twin studies have established the likelihood that genetic factors may influence or contribute to the development of autism. Three twin studies comparing concordance rates for autism in monozygotic and same-sex dizygotic twin pairs found

DIAGNOSIS AND CLINICAL FEATURES

The diagnosis of autistic disorder requires that a certain number of criteria in three symptom areas of social interaction, verbal and nonverbal communication and play, and repertoire of activities and interests be met. However, children meeting criteria for autistic disorder may

COURSE AND PROGNOSIS

Although most autistic children show improvement in social relatedness and language ability with increasing age, autistic disorder remains a lifelong disability, with the majority of

TREATMENT

Behavior therapy

Behavior therapy, which uses specific behavior modification procedures, may be helpful in establishing desired behaviors and eliminating problem behaviors in autistic children. After a

Psychotherapy

With the recognition of the biological basis of autistic disorder came the realization that psychodynamic psychotherapy in young autistic children, including unstructured play therapy, was not appropriate. Individual psychotherapy, with or without medication, may be appropriate for higher-functioning persons who, as they get older, may become anxious or depressed as they become aware of their differences and difficulties in relating to others.

Psychopharmacological treatment

In a subgroup of autistic children with target symptoms, such as temper tantrums, aggressiveness, self-injury, hyperactivity, and stereotypies, appropriate psychoactive agents

ANTIPSYCHOTICS

It was hypothesized that the stereotypies and hyperactivity seen in many autistic children were a function of increased dopaminergic activity. That was the rationale for the use of antipsychotics, which block dopamine receptors, in autistic children. In individually regulated doses of 0.25 to 4.0 mg a day, or from 0.016 to 0.217 mg/kg a day, the high-potency antipsychotic haloperidol proved more effective than placebo in reducing target symptoms. Side effects of sedation and neuroleptic-induced dystonia were seen at doses above therapeutic doses. No negative effect on learning or cognition was found, and in two studies haloperidol was shown to facilitate language development and learning in the laboratory. In

FENFLURAMINE

The finding of hyperserotonemia in one third of autistic children led to the hypothesis that autistic symptoms may be due to increased brain serotonin levels. That hypothesis in turn led to the study of fenfluramine, a serotonin depleter, in a

NALTREXONE

Similarities between the behaviors of autistic children and the behaviors of opiate addicts while intoxicated and during withdrawal led to the theory of opioid dysregulation in

SYMPATHOMIMETICS

The efficacy of amphetamines was investigated in autistic children because hyperactivity and inattention, frequently seen in such children, are ameliorated by amphetamines in

CLOMIPRAMINE

Clomipramine (Anafranil), an antidepressant, inhibits the reuptake of serotonin, which has been implicated in the pathogenesis of autistic disorder. A recent double-blind, placebo-controlled crossover study found clomipramine to be superior to both desipramine (Norpramin) and placebo in decreasing obsessive-compulsive symptoms, anger, and

CLONIDINE

The possibility that some symptoms of autism reflect hyperarousal and dysregulation of the adrenergic system led to the study of clonidine (Catapres), an alpha2 -adrenergic agonist that

Facilitated communication

More