Neurovascular signal changes in response to glucose infusion measured with resting-state fMRI at 7T

Motivation: To examine the impact of 2-hour glucose infusion on neuronal activity, potentially advancing our understanding of diseases such as diabetes and their regulation of intake, thermogenesis, and the neuroendocrine system. Goal(s): Determining whether prolonged glucose infusion affects neuronal activity as measured using rsfMRI at 7T. Approach: High resolution resting-state (rsfMRI) were acquired before and directly after glucose infusion in 9 healthy adult subjects. Neuronal fluctuations were characterized using Fourier-based spectral analysis. Results: In grey matter, significant differences between pre- and post-glucose infusion were observed, with higher post-infusion rsfMRI amplitudes across various frequencies, especially in the 0-0.15Hz range associated with neuronal fluctuations. Impact: Our results confirm that changing glucose levels modulate neuronal function. Extended glucose infusion increases mean signal power and induces increased signal variation in neuronal fluctuations. Future studies are needed to further understand the mechanisms behind this variance.