Regional correlation between fractional amplitude of low-frequency fluctuation (fALFF) and brain glucose uptake in anesthetized rats

Motivation: Several human studies have explored the relationship between glucose metabolism and RS-fMRI metrics. However, the relationship between glucose metabolism and RS-fMRI metrics under anesthesia remains unclear. Goal(s): This study explores the correlation between the fractional amplitude of low-frequency fluctuation (fALFF) and glucose metabolism measured by 18F-FDG PET in anesthetized rats. Approach: RS-fMRI and PET. Results: There is a strong correlation between fALFF and 18F-FDG uptake in the striatum and cingulate cortex, but no significant correlation in other brain regions. Impact: The findings suggest that fALFF could serve as a non-invasive marker for glucose metabolism in certain brain areas under anesthesia. These results may advance the use of fALFF in rodent studies on brain function, especially when PET data is unavailable.