Norepinephrine-mediated arousal fluctuations drive inverted U-shaped functional connectivity dynamics.
Level 5 - mechanism / opinion, no new human data
Mechanistic animal research combined with human neuroimaging
PubMed 41390822 · doi:10.1038/s41467-025-66436-x
What was done
Researchers integrated simultaneous functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) across humans and awake mice to evaluate arousal-related functional connectivity (FC) dynamics and behavioral performance. In awake mice, they combined invasive multimodal neural recordings and targeted manipulations of locus coeruleus-norepinephrine (LC-NE) neurons with simultaneous EEG-fMRI to test causality.
What was found
No numerical values, sample sizes, or test statistics are reported in the abstract. Qualitatively, arousal modulated inverted U-shaped global FC dynamics peaking at intermediate arousal levels in both humans and mice. This pattern correlated with arousal-modulated behavioral performance, and LC-NE manipulations in mice causally drove these FC dynamics dependent on baseline arousal.
Why it matters
This study provides cross-species evidence linking noradrenergic arousal states to large-scale functional network dynamics, offering a neural network explanation for the Yerkes-Dodson law.
Limits
Sample sizes, participant characteristics, effect sizes, and quantitative results are omitted entirely from the abstract. Invasive causal manipulations were conducted in mice rather than humans.
Cited by
- supports The relationship between motivation or arousal and task performance follows an inverted U-shaped curve (the Yerkes-Dodson law), where both insufficient and excessive motivation impair performance.