Aspects of connectivity in schizophrenia: Introduction

The hypothesis of prefrontal-temporolimbic disconnectivity, considered to b e relevant to the pathogenesis of schizophrenia, has been tested in 29 drug -naive schizophrenic patients, comparing the active with the remitted state . Method: A pre-post treatment design was applied to 29 drug-naive schizoph renic inpatients, 18 male, mean age 32 years, 11 female, mean age 32 years, mean duration of illness 29 months. Psychopathological symptoms were asses sed using PANSS, regional cerebral blood (rCBF) was measured by HMPAO-SPECT . RCBF values were calculated for 21 regions of interest after normalizatio n to cerebellum, and plotted by Euklidean diagrams using the ordinal, nonme tric, multidimensional scaling method. These diagrams represent similarity correlations visualized as spatial distances. High correlation levels as in dicated by small Euklidean distances have been interpreted as functional co nnectivity. Results: In active schizophrenia, functional disconnectivity wa s observed between prefrontal and temporal cortex. After remission, connect ivity was improved between temporolimbic and frontal cortex. Conclusion: Co mparing active with remitted schizophrenia, a frontotemporal disconnectivit y appears. Temporolimbic as well as frontolimbic connections restitute para llel to psychopathological improvement.