Course of psychopathology, cognition and neurobiological abnormality in schizophrenia: developmental origins and amelioration by antipsychotics?

Abstract

It is argued that schizophrenia has origins in events occurring during the first or early second trimester that are reflected in minor physical anomalies and which may at least in part predispose to later obstetric complications. This neurodevelopmental basis underlies certain neuromotor and psychosocial abnormalities of infancy and childhood, which are the early manifestations of what will be reconceptualised later as negative symptoms and (particularly frontal) cognitive dysfunction, but gives rise to positive symptoms only on the maturation of other systems necessary for their expression. This later emergence of psychosis reflects an active morbid process that is associated with increased accrual of negative symptoms and of general (but not frontal) cognitive impairment that may be ameliorated by effective antipsychotic treatment. The psychological or biological basis of this heuristic process is poorly understood. Contemporary re-appraisal of any impact of antipsychotics on the long-term course of schizophrenia must take into account what is known of the origins of the disease process with which such drugs might interact. Much recent work continues to indicate that very early events, during the embryonic\\fetal period, are important in, if not fundamental to, the genesis of schizophrenia; i.e. that there is a neurodevelopmental basis to the disorder. The present article seeks to establish a time-line relating early intrauterine adversity and dysmorphogenesis, through the onset of psychosis, to the chronic phase of the illness over adulthood; from this time-line, a schema is elaborated for a beneficial impact of antipsychotics on the course of psychopathology, cognition and, less clearly, neurobiological abnormality.