Pervasive Developmental Disorders: Etiology

Pervasive Developmental Disorders

Etiology

Autism Spectrum Disorders	Childhood Schizophrenia
Environmental Factors: Early in the study of autism, environmental factors were typically considered the basis of the disorder; during the 1970’s, environmental theories became less prominent and biological factors were more carefully considered	Environmental Factors: Maternal over protection, maternal rejection, stimulus deprivation, inconsistent parenting, severe emotional abuse
Biological Factors: Biochemical, sensorimotor, neurological and cognitive defects Central nervous system and brain circuits are abnormal Genetic predisposition – generally believed that there are gene mutations involved in autism; also increased likelihood of multiple incidence in siblings and second degree relatives	Biological Factors: High frequency of prenatal and perinatal complications (toxemia, vaginal bleeding, maternal illness), neurological damage, hereditary predisposition