Is a purpose of REM sleep atonia to help regenerate intervertebral disc volumetric loss?

The goal of this article is to stimulate spine research in sleep. Specifically, I ask whether REM atonia plays a mechanical function in assisting recuperative imbibition to diurnally influenced cartilaginous structures in mammalian species. Since the discovery of REM sleep, researchers have been looking to the midbrain and surrounding parenchyma in search for answers with much progress in the neuro-mechanisms around the reticular formation. But do we know definitively the mechanical effects of REM's atonia on all diurnally influenced mammalian tissues? To the best of the author's knowledge, this relationship has not been thoroughly investigated and requires a closer look.To appreciate the historical pursuit of REM sleep atonia's regulatory mechanisms, Michael Jouvet's study in 1962 [1] warrants honorable mention. Jouvet investigated subcortical activities in sleeping decerebrate cats. He measured EMG activity of neck muscles and found that muscle tone disappeared 4–5 times (for a period of about 6 min) over a 6 h course of sleep – even without the cortex. He also found that, during atonia, high voltage spiky waves appeared in the pontine EEG recording electrodes and waking EEG in the cortex. This apparent paradox (atonia and waking-like EEG activity) led him to coin the term "paradoxical sleep" and the research suggested the structures responsible for REM's characteristic identification of atonia were located caudal to the transection at the midbrain [2].The function of REM sleep continues to be enigmatic [3], with atonia well documented in humans and animals. Some have explained this as the loss of core muscle tone [4] and by others, as the total paralysis of the anti-gravity muscles of the body [5]. But, to date, the best functional hypothesis for this complete pseudo-paralysis is believed to be for the purpose of not acting out our dreams. It is understood that this idea has evolved from the disturbing effects of REM sleep behavior disorders. Here, an alternative