PT  - JOURNAL ARTICLE
AU  - Antoine Bergel
AU  - Elodie Tiran
AU  - Thomas Deffieux
AU  - Charlie Demené
AU  - Mickaël Tanter
AU  - Ivan Cohen
TI  - “Online” modulation of brain hemodynamics despite stereotyped running
AID  - 10.1101/2020.01.11.902932
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.01.11.902932
4099  - http://biorxiv.org/content/early/2020/01/14/2020.01.11.902932.short
4100  - http://biorxiv.org/content/early/2020/01/14/2020.01.11.902932.full
AB  - Theta and gamma rhythms coordinate large cell assemblies during locomotion. Their spread across temporal and spatial scales makes them 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. Theta rhythm and running speed were strongly coupled to brain hemodynamics in multiple structures, with delays ranging from 0.8 seconds to 1.8 seconds. Surprisingly, hemodynamics was also strongly modulated across trials within the same recording session: cortical hemodynamics sharply decreased after 5-10 runs, while hippocampal hemodynamics strongly and linearly potentiated, 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 despite stereotyped behavior.