Early-onset schizophrenia as a progressive-deteriorating developmental disorder: evidence from child psychiatry.

The developmental perspective as reflected by investigations of childhood and early-onset schizophrenia has become a major research area during recent years and contributed much to the understanding of schizophrenia at all ages. This paper reviews clinical features, neurobiological and neuropsychological findings in childhood and adolescent onset schizophrenia including some results of studies of the author on age at onset, premorbid symptoms, treatment and course. Childhood-onset schizophrenia is a rare disorder with a prevalence of one child in 10,000 before the age of 12 and a remarkable increase around puberty and early adolescence. Developmental events and precursors of schizophrenia cover a wide range of dysfunctions and disturbances including elevated rates of soft neurological signs and birth complications, slow habituation and high baseline autonomic activity, high rate of developmental disorders of speech and/or language and overall and specific cognitive deficits. Brain morphological studies and intelligence testing as well as investigations of the course provide evidence of deterioration. Therefore, early-onset schizophrenia can be understood as a progressive-deteriorating developmental disorder.