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bioRxiv
BIORXIV
bioRxiv
Cold Spring Harbor Laboratory

10.1101/2024.05.23.595327
preprint
1
Article
The Effects of Locus Coeruleus Optogenetic Stimulation on Global Spatiotemporal Patterns in Rats
Anumba Nmachi
Kelberman Michael A.
Pan Wenju
Marriott Alexia
Zhang Xiaodi
Xu Nan http://orcid.org/0000-0002-3900-3220

Weinshenker David
Keilholz Shella
23 5 2024
2024.05.23.595327http://biorxiv.org/lookup/doi/10.1101/2024.05.23.595327
nihpp-2024.05.23.595327.pdf
ABSTRACT

Whole-brain intrinsic activity as detected by resting-state fMRI can be summarized by three primary spatiotemporal patterns. These patterns have been shown to change with different brain states, especially arousal. The noradrenergic locus coeruleus (LC) is a key node in arousal circuits and has extensive projections throughout the brain, giving it neuromodulatory influence over the coordinated activity of structurally separated regions. In this study, we used optogenetic-fMRI in rats to investigate the impact of LC stimulation on the global signal and three primary spatiotemporal patterns. We report small, spatially specific changes in global signal distribution as a result of tonic LC stimulation, as well as regional changes in spatiotemporal patterns of activity at 5 Hz tonic and 15 Hz phasic stimulation. We also found that LC stimulation had little to no effect on the spatiotemporal patterns detected by complex principal component analysis. These results show that the effects of LC activity on the BOLD signal in rats may be small and regionally concentrated, as opposed to widespread and globally acting.
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