I'm trying nowadays to pay attention to symptoms and patterns. I've noticed that the nap followed by tingling in hands and feet is typically followed by heat.

My hands and feet get cold quite often now, so I've been trying to nap lately to get them warm again. It invariably works even if the nap is short.

Anyway, I think it must be vascular, as suggested, at the same time as nerves are affected, or shortly thereafter.

I wonder what cortisol does to/for/with/against B12. Stress of course typically affects cortisol levels and we know stress depletes B12.

Whatever chemical it is that's being released after I nap - I wish I knew what it was. Then I'd take more of it from other sources. The 'tingling' isn't painful or annoying; it's almost comforting. It seems to be related to the body's effort at healing.

I have not yet found a medical reference that shows that "stress" depletes B12.

If you have one I'd like to see it.

There are laymen oriented sites on the net that clump Bcomplex together as helpful for "stress". But I do not think that the B12 in them is adequate for supplementation.

More on B12.
http://lpi.oregonstate.edu/infocente...ns/vitaminB12/

When body parts get cold and then warm up, tingling is typically felt by everyone.

There is a long list of hormones and other substances that are released before, during, and following sleep. Many of them are dependent upon ambient light, which is naturally controlled by sunlight (day and night). This changed significantly only a little over a century ago as electric lighting became common in homes & workplaces, raising havoc, for the first time, with human circadian rhythms. So part of it depends on how you take your naps; time of day, light or dark room, blindfolds, etc. (The amount of light necessary to bring about these changes is small enough to penetrate eyelids; even some/most blind people get enough light somehow to effect these changes).

So even if you knew the list of substances, you would then need to determine which one - or ones in combination - out of dozens (hundreds?) produced the effects you mention.

Messing with these substances is risky unless there is a legitimate medical need/reason to supplement them artificially, and even then there are still risks attached - as with anything we take in - there's an equation of benefit vs. risk that needs to be addressed. There are LOTS of natural substances & hormones that we could take artificially that would make us "feel" better/good. Some athletes do it for "performance enhancement", and as with street drugs (and some of the hormones athletes take are now considered street drugs) these substances make the takers feel great at first, and then the hell (and problems) begins....

For example, endorphins (a.k.a. "endogenous morphine") are opioid-like hormones that can make us feel better in a lot of ways, and have many useful functions when released naturally/normally, but too much of them can result in depersonalization disorder, and sudden cessation is believed to play a part in postpartal depression/psychosis.
http://en.wikipedia.org/wiki/Endorphin

Messing with these substances and their delicate balance requires a lot of research, testing, and monitoring, and should only be considered when there is proven medical need and guidance/supervision. The same can be said for many of the supplements and natural substances marketed online and elsewhere. Natural ≠ safe.

Doc

Doc

Haven't been able to look into it very much as computer is gimpy, google
cortisol and microphage migration inhibitory factor. Kind of hard to understand the biochemistry and I'm not sure if I have it all straight but it stated cortisol stimulates MMIF which is a cytokine that intensifies pain and was said to eventually override the pain killing effects of cortisol. I wondered if the pain and stress of PN stimulated cortisol and the resulting MMIF stayed around longer when cortisol levels dropped, caused more pain which again stimulated cortisol which again stimulated MMIF. I don't know if I have it all straight at this point or if its is too complicated for us to understand anyhow.
Zygo