P.S. The website design is also imho a bit wacky.
Happy to answer any questions, if I'm not understanding your statement correctly.
By "regulating skeletal muscle tone" do you mean as an input? Or as a target?
We've mostly focused on neuro, though we did an experiment in Vagal stimulation, but you could never be sure what you were measuring, so we ditched that and focused on the area with the most research.
PTAS (the technical term for the stimulation) has considerable amount of research behind it with impactful results.
Always keen to learn more if there is something in muscle tone you think we should be looking at.
Insulin response and other metabolic factors seem currently not measurable non-invasively, like EEG. That's why I was focusing on muscle tone as an easily available parameter which can be measured continuously and non-invasively, in line with EEG. Temperature is another similar parameter and I've seen a couple of studies showing reduced frontal lobes' temperature promotes sleep.
It can seem tricky to reduce it without pharma or techniques performed while awake, but I've collected a corpus of research which may allow to emulate the action of e.g. GABA without adding the actual GABA (which is thought to induce muscle paralysis in sleep), thus non-invasively promoting the reduction of skeletal muscle tone.