NEUROMUSCULAR ORGANIZATION OF SHIVERING 
diaphragm active, you get accessory muscles that are inspiratory 
and these are predominantly in the neck and jaw. I wonder if you 
made any attempt to correlate the pattern of onset of shivering in 
muscles with the pattern of onset of these accessory muscles as 
asphyxia is brought into play? 
DR. KAWAMURA.: This was not measured. It would be worth- 
while to investigate this to determine whether or not the phasic 
activity of the accessory muscles facilitates shivering. 
DR. LIM: There is one comment. Dr. Hensel tells me that the 
carbon dioxide inhalation, five to six percent, increases shivering 
which phenomenon may be in favor of this last possibility in raising 
the respiratory activity. 
DR. HENSEL: Yes. 
DR. STUART: One important aspect ofthis paper is the demon- 
stration of synchronous activity in antagonistic muscles during shiv- 
ering. This, together with the shivering tremor frequency of 10-12 
cps, is distinctly different from the Parkinson tremor (4-7 cps) in 
which antagonistic muscle activity is alternating. Now, you showed 
us evidence that the flexor and extensor fire synchronously. 
DR. KAWAMURA: Yes, I did. 
DR. STUART: I h ink this is unique in the literature. Have you 
recorded the tension developed in antagonistic muscles during shiv- 
ering? Or do you know of any accounts of it? 
DR. KAWAMURA: No, I have never measured that. 
DR. HENSEL: Did you record hypothalamic temperature during 
your experiments with local cutaneous heating? 
DR. KAWAMURA: No, I did not. 
DR. HENSEL: That is the question, because we found in the cat 
that local cutaneous heating might cause quite considerable changes 
in hypothalamic temperature without any considerable change in 
rectal temperature. 
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