“Lasers Stimulate New techniques in Nerve Studies” Biophotonics Oct 2006.
Pretty cool review article on how they can use lasers for stimulation of nerves without using electrical impulses. The primary advantages are they they do not damge the nerves and have less artifacts to deal with. Wavelength optium is 2.1 to 4.0 um They have been using a Ho:YAG at 2.12 um. They have now developed a diode laser at 1.85um wavelength. They are looking at 300 to 600um tissue penetration for peripheral nerve stimulation.
So far it appears the mechanism for the change in the action potential in the nerves requires a change in a temperature gradient.
It appears that maybe someday we will get some answers…… So it is looking like our laser anesthia maybe a thermal effect???