Massimiliano Dieci

Language and thought disorder in schizophrenia: brain morphological correlates

In this magnetic resonance imaging study, the authors analyzed the relationships between frontal and temporal lobe volumes, volumes of ventricular system subdivisions and clinical and neuropsychological aspects of language and thought disorder in a group of 19 young schizophrenic patients. Schizophrenics showed enlargement of lateral ventricles, especially of the central and occipital segments compared with 15 age and sex matched healthy controls but no differences were present in prefrontal, temporal lobe and superior temporal gyrus volumes. Prefrontal volume was inversely correlated with Thought, Language and Communication (TLC) scale total scores; left superior temporal gyral (STG) volume was positively correlated with verbal fluency test performance; higher total ventricular volume was significantly correlated with poor performance to a sentence generation test; STG laterality index was correlated with global TLC scores, the more severe the thought and language disorders, the relatively smaller the left and larger the right STG. These results suggest a complex neuroanatomical substrate for thought and language disorders in schizophrenia.

Stability of cerebral ventricular size from the appearance of the first psychotic symptoms to the later diagnosis of schizophrenia

We report preliminary evidence that ventricular size is static in the period between the emergence of the first psychotic symptoms and the subsequent diagnosis of schizophrenia

A reconsideration of the relationship between cerebral structural abnormalities and family history of schizophrenia.

In a study of 229 schizophrenic patients for whom reliable family history information was available, ventricular size and incidence of ventricular enlargement were found to be greater in male cases without a family history of schizophrenia. A significant sex by family history interaction on cerebral ventricular dimension was detected. The age-corrected morbid risk for schizophrenia was lower among first degree relatives of male probands with ventricular enlargement vs. those with normal ventricles, but similar in relatives of females with and without ventricular enlargement. On the other hand, no association was found between family history and degree of cortical atrophy. A meta-analysis of published studies on the issue revealed 20% larger ventricles in patients without any known genetic predisposition for schizophrenia.

Cerebral ventricular enlargement as a generalized feature of schizophrenia: a distribution analysis on 502 subjects.

Enlargement of cerebral ventricles is one of the most replicated biological features, and the one quantitatively most deviant in schizophrenia. It occurs in the early phases of the disease and may have pathogenetic relevance. Whether this abnormality is limited to a specific subgroup of patients or is a common feature to most or all patients affected by schizophrenia, however, is still a matter of debate. The answer to this question would improve our comprehension of the nature of this abnormality and contribute to the debate between the competing hypotheses of biological homogeneity vs heterogeneity of schizophrenia.We performed a distribution analysis of lateral ventricular dimensions of 340 schizophrenic patients and 162 non-psychiatric controls. All subjects underwent cerebral computerized tomographic scan, and ventricular dimensions were expressed as ventricular brain ratio (VBR). After removing the effect of confounding variables (age, sex and type of scanner) on individual VBR, data were power-transformed and different distribution hypotheses were tested by means of the maximum log-likelihood ratio method. Our findings indicate that, in the mixed sample of patients and controls, a mixture of two gaussian curves represents the distribution better than a single gaussian curve, but no evidence emerged leading to rejection of the normality hypothesis in the schizophrenic patients sample. Lateral ventricular enlargement in schizophrenia is not a marker of a discrete subgroup of schizophrenia, but occurs in most, if not all, schizophrenic patients. This supports the hypothesis of biological homogeneity of the disease, at least relative to its major brain morphological abnormality.

Non-selective impairment of Wisconsin Card Sorting Test performance in patients with schizophrenia

Sixty-two schizophrenic patients and 26 healthy volunteers were administered the Wisconsin Card Sorting Test (WCST) a task putatively specific for frontal functions and the Wechsler Adult Intelligence Scale (WAIS). The purpose of this study was to evaluate the presence of specific frontal lobe deficits in the course of schizophrenia and the capacity of these tasks to discriminate between patients and controls. Schizophrenic patients showed a poorer performance than control subjects in both tests. No evidence emerged to support a higher discriminant power for the WCST in identifying schizophrenic subjects from healthy controls compared with the WAIS. Our data suggest that the deficit in WCST performance is not selective, but rather part of a more generalized neuropsychological impairment in schizophrenic patients.

Epithalamus calcifications in schizophrenia

Abstract We evaluated the prevalence and the size of epithalamus calcifications (EC) and choroid plexus calcifications (CPC) on computed tomography (CT) scans in a group of 64 schizophrenic patients and in a group of 31 healthy controls. The associations between cerebral calcifications, demographic variables, and other brain morphological characteristics (particularly cerebral ventricular size and cortical atrophy) in both, patients and controls, were also considered. A significant increase in size of the epithalamic-region calcifications in schizophrenic patients was found, whereas there was no evidence of increase in both, dimension and prevalence, of choroid plexus calcification. Such dimensional increase was unrelated to the duration of illness and therefore did not seem to be iatrogenic or secondary to the disease. A correlation was found between epithalamus calcifications and cortical atrophy and third-ventricle enlargement, suggesting that calcifications of this cerebral region may be associated with lesions of third-periventricular areas and of circuitries hypothesized to be involved in the pathophysiology of schizophrenia.

Brain morphology in schizophrenic disorder: Prevalence and correlates of diffuse (Cortical and subcortical) brain atrophy

The assessment of the prevalence of CT pictures of «diffuse brain atrophy» in schizophrenia and the analysis of the clinical correlates of this finding are the questions to which this study was addressed

Outcome of positive and negative symptoms during neuroleptic therapy in schizophrenia

Abstract In a 1-year follow-up of 40 schizophrenic patients treated with classic neuroleptic drugs, a significant improvement of both positive and negative symptoms was detected. Positive symptoms improved earlier and more consistently. A reduction of negative symptoms, although less significant, was however evident in the second semester of follow-up.