A FDG-PET and fMRI Study on Glucose Metabolism and Hemodynamic Response during Visual Attentional Performance in Schizophrenia

Abstract

This research investigated the correlation between regional cerebral glucose metabolism rate (rGMR) of [18F] fluorodeoxyglucose positron emission tomography (FDG-PET) and hemodynamic response of blood-oxygen-leveldependent (BOLD) fMRI in schizophrenia during visual attentional performance. PET, MRI and fMRI images of 17 unmedicated schizophrenia patients and 38 healthy controls were acquired. A visual attention task was administered during the FDG uptake period and during the fMRI scan. Statistical parametric mapping (SPM) analysis was performed on the PET and fMRI images. Hemodynamic response curves were extracted from the frontal and temporal cortices, Anterior Cingulate Cortex (ACC), caudate and thalamus. The Area under the Curve (AUC) was calculated for each region and correlated with rGMR obtained from PET images. The results indicated that (1) Although the spatial patterns of rGMR and hemodynamic response SPMs are different, the rGMR and hemodynamic responses were significantly correlated in the frontal and temporal cortex, anterior cingulate cortex, caudate and thalamus for all subjects; (2) The patterns of the correlations are different between schizophrenia patients and controls. These results confirm the findings of our previous PET and fMRI study during auditory attentional performance, suggesting that altered blood flowmetabolic processes during neuronal activities may underlie the attention deficits in schizophrenia, which may be useful for the early diagnosis of schizophrenia.