The neurodevelopmental model of schizophrenia suggests that the brains of individual who develops schizophrenia may either experience over aggressive pruning or because of developmental issues during 2nd trimester of oregnancy, their brains may have fewer dendrite branches to begin with. In later case, the normal pruning process leaves them with an inadequate number. Parental developmental abnormalities are often reflected in minor physical abnormalities, alternatively known as physical anomalies, that can be detected after birth. These anomalies include minor abnormalities of the head, feet, hands or face.
Many infants have single anomaly, but those who later diagnosed with schizophrenia may have several. Thigh it's not known exactly at what point of parental development these anomalies occur, it's thought that they are associated with the process of neurodevelopment that occur in 2nd trimester. The number of anomalies don't likely to have any genetic basis because siblings of schizo patients don't have an excess number. This excess of anomalies found in schizophrenia is not found in other psychotic disorders but found in Down Syndrome where parental neural involvement is clear.
Apart from brain development issues, neuromotor system development seems to be affected in schizophrenia. Kids who may later develop schizophrenia often show unusual expressions emotion & motor behavior. One finding that has emerged from use of scanning techniques is that some individual with schizophrenia jave significantly larger cerebral ventricle. However, some enlargement of ventricle seem to occur naturally. In general, people's ventricle become larger with age. Though enlarged ventricles are found in conditions like alcoholism, traumatic head injury & severe mood disorder involving psychosis.
Result of a study of 15 sets of MZ twins, in which only one of each pair had been diagnosed with schizophrenia were of particular interest in understanding the role of enlarged ventricles. The twins with schizophrenia had enlarged lateral & 3rd ventricles compared to their twins who didn't have diagnosis. They were also found to have a reduction in size of brain's areas that are involved in thinking, concentration, memory & perception. All these aspects of behavior are affected in schizophrenia. In all but one of the twin pairs with schizophrenia also had reduced brain volume when compared to his/her healthy twin.
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