IRVING 



the rate, the velocity, the thresholds, or the temperature of cold 

 block for the actual nerve tissues in the periphery. There must be 

 some way to get at this question. 



PROSSER: What would be the best animal to use? Hensel's 

 work has been done almost exclusively with cats. 



IRVING: People are pretty good. 



PROSSER: But you cannot go in and record the nerve impulses. 

 I want an animal in which you can go in and record the nerve 

 impulses. 



IRVING: I would take a bird, like a gull, because for one thing 

 they are not pleasing animals; you have no sympathy for them at 

 all. By just putting blindfolds over their heads you can pretty well 

 immobilize them, and when so quieted you can readily expose 

 their long bare legs to cold. 



EAGAN: I think a lot could be done by using Irving's and 

 Miller's ball-bearing test on fingers. When you use bilateral com- 

 parisons you can so simply compare the adapted side with the 

 controlled side. 



PROSSER: Is this sensory adaptation which may be occurring 

 due to the temperature per se, or might it be due to changes in 

 oxygen supply? 



IRVING: Temperature, per se, must beafactorin this habitua- 

 tion. However, since cold does reduce the circulation, then oxygen 

 supply is also a probable factor. 



ADAMS: You can superimpose the effects of anxiety, induced 

 either by emotional stress or by pain on the cold induced vaso- 

 dilation response. In some subjects where we have measured cold 

 induced vasodilation responses, we find that we can prolong the 

 period of the peripheral vasoconstriction (with the finger surface 

 temperature at G) up to 25 minutes in the ice bath by super- 

 imposing the effects of anxiety on the basic pattern of the response. 



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