Here is an observation that perhaps we all have known about but I have not heard of it being investigated. Twice now while running I have run up and over the steepest hill in my regular 5k course and suddenly realized I had done so without tiring my legs and without excess shortness of breath or even thought about it that has always previously been present. I wondered,"why?" Then I recalled at least three cases of clients who had problems with missing fingers who answered when asked about what happened that each had been working with with a table saw and suddenly noticed blood all over their work to discover they had cut themselves with out knowing it until seeing the blood. The question of how anyone could cut off fingers without felling it may be the same situation as my running over the hill without knowing it.
I recall reading about a surgeon who visited a medical school in China to witness acupuncture as an anesthetic who reported on a case of eye surgery on a patient with no other anesthetic. The case was one that should have created excruciating pain but did not with the Chinese surgeon. Something is happening in all those cases that indicates something to due with brain chemistry perhaps. Also I recall a Dr. G. Young friend telling how he used acupuncture on cows to do Cesarean section operations on cows in his practice. It seems that some involuntary situation occurs over which apparently we have no control. If we can learn to use whatever is responsible in a constructive way I might be able to run without feeling fatigue for example. It could be the end of the need for anesthesia in surgery. That might also be involved with forgetfulness in humans. I'm sure all reading this can recall similar situations. It seems to me that research in brain chemistry may have the answers to such questions. Of course it is known that pain can be for good reason that must be considered.