 |
 |
Authorised e-mail: Meditating on yogic science |
|
Re: Meditating on yogic science
With respect to unilateral forced nasal breathing
(http://www.thelancet.com/newlancet/sub/issues/vol351no9108/news_f1038.html), I wish to
bring to attention a physiological phenomenon (Influence of Lateral Posture on Sweating:
Does Posture alter the Sympathetic outflow to sweat glands? Jayant S Vaidya, Ramesh A
Dhume. Ind J of Physiol & Pharmacol April 1994, 38(4):319-322. Quoted in Minerva, Br
Med J, 4 Feb 1995, Vol 310, p 340)
When one lies down on one's side, it is only the upper half that sweats--ie, if one is
lying on the left side the right half sweats and vice versa. There is a clear mid-line
demarcation that can be measured by reduced galvanic skin resistance, felt moist, and
even seen, especially in the hot and humid climate of Goa, India, where I first observed
it. This suggests that the sympathetic chain, which controls the sweating via its
cholinergic outflow on that side, can be easily switched on or off by a simple change of
posture. The sympathetic chain theory is compatible with the finding that nasal
congestion of the left nostril is usually relieved, probably by vasocontriction by lying
on the right and vice versa. This phenomenon could have implications in
autonomic-central nervous system connections and the possibility of conscious control of
autonomic nervous activity and new therapeutic avenues. In addition, it is an easily
observable window to the autonomic system. I have wondered how this ties in with the
known changes in cardio-respiratory function and the possible yogic effects of lateral
posture. I have wished to test whether lateral posture alters activity in any other
part of the nervous system; but the conventional supine posture during scans is
difficult to change and I have yet to find someone willing to do PET or MRI scans in
lateral postures for investigating this. Any takers on the Lancet Interactive?
Jayant S Vaidya
