CENTRAL AND PERIPHERAL MECHANISMS 
DR. LIM: That is very possible. 
DR. HENSEL: There is practically nothing. 
DR. MINARD: Dr. Lim mentioned Dr. Benzinger's work, and I 
would like to point out that Dr. Benzinger found it possible in the 
human subject to bring about this dissociation between skin and deep 
temperature. He also felt, asDr. Lim does, that this is important in 
determining the regulatory responses in the conscious unanesthe- 
tized human subject. It is possible to bring about such dissociation 
by having the man either at rest or working, in a hot or cold environ- 
ment. By selecting various environmental conditions and work rates, 
it is possible to obtain a wide variety of core and skin temperatures. 
DR. LIM: In that connection, I was very happy to learn recently 
of Dr. Benzinger's finding, that the skin temperature plays a very 
important role in the cold. This was exactly what I found. 
DR. MINARD: I would say, from what I know of Dr. Benzinger's 
work, that there is no disagreement whatever in your results and 
his regarding cold conditions. I think he has come to some interpre- 
tation of a mechanism acting centrally, but as far as the experi- 
mental findings go, there is absolutely no disagreement between his 
findings and yours. 
DR. HENSEL: I think it is necessary to emphasize that Dr. 
Benzinger's concept is applied only to sweating in human subjects, 
not to vasomotor responses, nor to any kind of cold responses. It 
is a concept that should be restricted to mechanisms. I think he 
would completely agree with your findings, and I must say that I am 
very happy about them too. They agree very well with our results 
in the unanesthetized cat, where we made the local hypothalamic 
temperature change by means of a chronically implanted the rmode. 
DR. LIM: In some of our experiments we studied the contribution 
of the vertebral arteries to the cerebral circulation. Of course, the 
brain circulation is mainly through the carotid arteries. Ligation of 
the vertebral arteries did not make much difference in our experi- 
mental results, so we think, at least in dogs, that the blood going to 
the brain through the vertebral arteries is rather small. 
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