Which characteristics of schizophrenia predate psychosis?
Neuropsychological and brain structural abnormalities are present in first onset schizophrenia; the balance of evidence is that in the majority of cases these are developmental in origin. A proportion of first degree relatives also show lateral ventricular enlargement, cortical volume decrease and possibly loss of the normal cerebral asymmetry; these findings suggest that certain families transmit a genetic defect in the control of neurodevelopment. On the contrary, decrement in left hippocampal volume appears to be secondary to perinatal hypoxia. High risk, follow-back and cohort studies all demonstrate that preschizophrenics as a group show deviant development; delayed milestones, lower IQ, solitary play, excessive anxiety, and minor neurological problems are all common. It seems likely, but not proven, that these are a manifestation of underlying neurodevelopmental disorder.
Davies
N
N
Department of Psychological Medicine, Institute of Psychiatry, London, U.K.
Russell
A
A
Jones
P
P
Murray
R M
RM
D000293:Adolescent; D000328:Adult; D002552:Cerebral Ventricles / Q000002:abnormalities; D002648:Child; D002675:Child, Preschool; D003072:Cognition Disorders / Q000150:complications / Q000175:diagnosis; D005260:Female; D006801:Humans; D008297:Male; D011618:Psychotic Disorders / Q000175:diagnosis / Q000523:psychology*; D012559:Schizophrenia / Q000150:complications / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D012917:Social Adjustment; D014888:Wechsler Scales