Autism As A Developmental Disorder Of Brain Functi
Earlier viewed as the behavioral response of toddlers or preschool children to inadequate parenting, we know today that autism is a developmental disorder of the immature brain that affects (1) sociability, (2) verbal and nonverbal communication and imaginative play, and (3) cognitive and behavioral flexibility. It has a wide range of severity and is not rare. It has many non-genetic and genetic etiologies. Single gene defects are rare as recurrence within sibships is under 10%. Some children may inherit excess vulnerability to particular--as yet undefined--trivial, usually easily tolerated environmental insults. As autism is behaviorally defined, it has no exclusionary etiologic or physical criteria: what counts is what brain circuits are dysfunctional, not what made them so. Stereotypic purposeless movements, joint laxity, toe walking, and apraxia and a mixture of hyper- and hypo-reactivity to sensory stimuli in any modality are common. Sleep disorders and difficulty attending to activities introduced by another person are troublesome. Cognition ranges from mental retardation to normal IQ, with uneven underlying skills and concreteness. A third will have experienced at least two unprovoked epileptic seizures by adolescence or have had subclinical EEG epileptiform activity in slow sleep. All children who do not speak well require definitive assessment of hearing. For clinical purposes, if the history and clinical examination do not suggest a diagnosable biologic condition, results of powerful research tools like extensive cytogenetic, molecular, biochemical, and imaging tests rarely modify management. The most effective interventions are early intensive education of the child that addresses both language and behavior, and training of parents in behavior management strategies. Medications do not alter outcome but may help some troublesome behaviors., http://www.100md.com