HETEROTHEPMY IN HOME OT HEP MS 



PROSSER: It might be that these other more complex inte- 

 grated functions are superimposed upon peripheral change. 1 do 

 not think one would expect a single line of defense here, but a 

 double line of defense. 



IRVING: I do not see how the nervous system can possibly work, 

 anyway. What I mean is, how can it maintain the constancy of appre- 

 ciation for external conditions through a thermo- labile system 

 which changes so grossly in many of its velocity and frequency 

 functions? A gram remains a gram, and that is that. A millimeter 

 remains amillimeterand that is that.lf the universe changed dimen- 

 sions as it changed temperature, we would go nuts; we would not be 

 here. 



EAGAN: There was an experiment we did in which four subjects 

 exposed one hand in a cold box for 12 hours per day for ten consecu- 

 tive davs, the finger temperatures being maintained between 10 C 

 and 15 G during the period of exposure. The latter was accom- 

 plished by having the subject withdraw his finger slightly as the 

 finger temperature increased or decreased towards 10 Cor insert 

 it farther into the cold box as it increased towards 15 C. The 

 subjects complained quite a bit at first, especially as it was getting 

 toward the 10 C side of things. As the days passed, their cold 



tolerance was greatly increased and they would even go to sleep 



o 

 with finger temperature at 10 C, a temperature which was too 



painful in the beginning to even consider any sleep. Interestingly 

 enough, when theydid go to sleep, the finger temperatures invariably 

 rose; we had to awaken them so that they could shove their hands 

 into the cold box a little further. In general, I feel that this experi- 

 ment nicely demonstrates a decrease in the discomfort due to cold 

 as a result of continuous exposure. 



IRVING: I think that is very important. Even though we say 

 "pain" is not physiologically definable as yet, it is nevertheless 

 a very important fact. Pain is pretty real, especially pain from cold. 

 A person unaccustomed to cold just cannot conceal it. I think the 

 mechanisms responsible for this habituation present a most inter- 

 esting question. As a result of habituation the re is repression of the 

 sense of pain, but we do not know whether there is any change in 



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