Adaptive modulation of brain hemodynamics across stereotyped running episodes
Antoine Bergel, Elodie Tiran, Thomas Deffieux, Charlie Demené, Mickaël Tanter, Ivan Cohen
Received Date: 28th January 20
Theta and gamma rhythms coordinate large cell assemblies during locomotion, but they are spread across temporal and spatial scales hence challenging to observe. Additionally, the metabolic cost of these oscillations and their contribution to neuroimaging signals remains elusive. To finely characterize neurovascular interactions in running rats, we monitored brain hemodynamics with functional ultrasound and hippocampal local field potentials in running rats. Peaks in theta power and running speed were reliably followed by a surge in blood flow, with delays ranging from 0.8 to 1.8 seconds, depeding on the structure. Surprisingly, hemodynamics were strongly modulated across trials within the same recording session: cortical blood flow sharply decreased after 5-10 runs, while hippocampal blood flow strongly and linearly increased, particularly in the CA regions. This effect occurred while running speed and theta activity remained constant, and was accompanied by increased power in hippocampal high-frequency oscillations (100-150 Hz). Our findings reveal distinct vascular subnetworks modulated across fast and slow timescales and suggest strong adaptation processes over the repetition of a stereotyped behavior.
Read in full at bioRxiv.
This is an abstract of a preprint hosted on an independent third party site. It has not been peer reviewed but is currently under consideration at Nature Communications.