Thalamic volume in first-episode and chronic schizophrenic subjects: a volumetric MRI study

The thalamus, as a composite of several functionally very different nuclei, is a major relay and filter station in the CNS and is significantly involved in information processing and gating. The aim of our study is to investigate first-episode and chronic patients and controls to shed light on the potential pathogenetic role of the thalamus in schizophrenia and to assess the relationship between thalamic volumes and psychopathology ratings.

Forty-three male right-handed chronic and 25 male right-handed first-episode schizophrenic patients treated at the psychiatric hospital of the Ludwig-Maximilians University in Munich and 50 male control subjects were enrolled into the study. Demographic information and current symptom profile of all schizophrenic subjects were assessed using a semistructured interview, including a variety of measures relevant to the study. Volumetry of the thalamic gray and white matter was obtained with 1.5 T MRI, using the BRAINS software application.

No significant differences regarding thalamic volumes were detected across groups. However, negative symptoms were significantly correlated with thalamic volumes in first-episode patients, whereas duration of illness and extrapyramidal symptoms were related to thalamic volumes in chronic patients.

Our findings indicate that, while the thalamus might be involved in the pathogenesis of negative symptoms, thalamic volume reduction is not a required element in the pathophysiology of the schizophrenic phenotype.