A prospective follow-up study of brain morphology and cognition in first-episode schizophrenic patients: preliminary findings

Time course of cerebral ventricular enlargement in schizophrenia supports the hypothesis of its neurodevelopmental nature

In the absence of direct and conclusive data demonstrating the 'neurodevelopmental hypothesis' of schizophrenia, several neuromorphological findings provide relevant clues in support of it. In this paper, we review a number of results obtained by our group in this area of research. In particular, the demonstration of stability of cerebral ventricular dimensions both in chronic schizophrenia and around the onset of the disease, and that of an identical effect of ageing on this morphological feature in large samples of patients and controls, strongly support the neurodevelopmental nature of brain pathomorphology in schizophrenia.

Obstetric complications and age-related changes in brain morphology in schizophrenia

Birth problems can lead to changes in brain morphology in the general population and an increased prevalence of both birth problems and altered brain morphology are found in patients with schizophrenia. The purpose of this study was to test the hypothesis that these two findings are related. Birth history and the size of ventricular and sulcal spaces from nine regions of the brain were assessed in 80 male subjects with schizophrenia. No differences were found between patients with and those without a history of birth problems for the size of any brain space; however, ventricular size increased significantly with age in patients who had no birth complications but not in patients with a history of birth problems. The size of cortical sulci increased with age in patients with and those without a history of birth problems. These results suggest that region-specific rates of change in size may identify clinically meaningful patients subgroups.

Hippocampal age-related changes in schizophrenia: a proton magnetic resonance spectroscopy study

We have used proton magnetic resonance spectroscopy to study in vivo N-acetyl aspartate (NAA), choline and creatine in the hippocampi of 26 schizophrenics and 38 normal controls. Measurements of NAA suggest that age-related neuronal loss occurs at a similar rate in schizophrenics and controls. On the other hand, we observe in schizophrenics age-related choline abnormalities not present in controls. We suggest that these age-related changes may be related to an abnormal myelination process and contribute to the observed clinical deterioration associated with schizophrenia.

Schizophrenia, the heteromodal association neocortex and development: potential for a neurogenetic approach

The heteromodal association neocortex is believed to be a major site of involvement in schizophrenia. This system includes the prefrontal cortex and portions of the superior temporal and inferior parietal cortices, which are linked in cognitive networks observing complex executive functions. The heteromodal cortex is highly elaborated in humans and is believed to continue to develop past birth. The neuropathology of schizophrenia is likely to be heterogeneous and appears to involve developmental abnormalities, with a prominent genetic component. However, the genes involved in the development of the neocortex, and particularly the heteromodal cortex, are not well understood. A candidate-gene approach to schizophrenia using techniques of differential expression might now be feasible and could illuminate the basic neurobiology of the heteromodal cortical network.