Tight Coupling of Resting-State BOLD Fluctuations with Intracortical DC Changes in Rat Somatosensory Cortex during Prolonged Medetomidine Sedation

Wen-ju Pan¹, Matthew Magnuson¹, Garth Thompson¹, Dieter Jaeger², Shella Keilholz¹

To investigate the neural correspondence of the resting-state BOLD signal fluctuations, simultaneous fMRI and intracortical electrophysiological recording were performed in rat somatosensory cortex under medetomine sedation. During prolonged medetomine administration (1-6 hours), the BOLD signal in the low frequency powers changed from <0.1-Hz to a combination of <0.1 Hz and a localized peak at 0.2-Hz. The intracortical DC/LFPs were correlated to both peaks of the BOLD signal at a time lag of ~2.5 s.