Low temperature may stop human cells’ daily rhythms through a critical change in their activity

Cold exposure suppressed circadian oscillations in cultured human cells in a reversible pattern consistent with Hopf bifurcation.

Human cell culture experiments and a mammalian circadian clock mathematical model tested low temperature, rewarming, and 24-hour temperature-cycle resonance effects on circadian amplitude.

The key cold-sensitive rhythm loss was shown in cultured cells, while human hair follicle cells were not significantly temperature-sensitive and whole-body effects were not tested.