Peter Herman1,2, Robert N. S. Sachdev3, Basavaraju G. Sanganahalli1, Fahmeed Hyder1,4
1Department of Diagnostic Radiology, Yale University, New Haven, CT, United States; 2Institute of Human Physiology, Semmelweis University, Budapest, Hungary; 3Department of Neurobiology, Yale University, New Haven, CT, United States; 4Department of Biomedical Engineering, Yale University, New Haven, CT, United States
Evoked responses in functional studies show baseline dependence, we asked if we can observe baseline differences in power of spontaneous fluctuations of BOLD signal. We compared spontaneous neural and BOLD signal fluctuations in high and low energy baseline states of light (domitor) and deep (α-chloralose) anesthesia. Extracellular electrodes were used to measure local field potential (LFP) and multi-unit activity (MUA) from middle cortical layers of rat brain and compared these neural signals with BOLD signal (11.7T). Results show that the power of spontaneous LFP or MUA activities is correlated with the magnitude of BOLD signal fluctuations in a baseline-dependent manner.