ROLE OF THE PROSENCEPHALON IN SHIVERING 
DISCUSSION 
DR. FREEMAN: You are familiar with the experiments in which 
electrodes are implanted in the septal and hypothalamic areas 
whereby animals can be induced to stimulate their own brains, as 
power to avoid this self stimulation. I wonder, one often hears 
phrases as "trembling with joy "and "quaking with fear." How do you 
think such manifestations of tremor activity are related to the 
shivering process? 
DR. STUART: First, we must distinguish between pathological 
tremors that are 4 to 7 cycles/sec, in which the agonist- antagonist 
activity is alternating, and the 9 to 11 cycles/sec shivering tremor, 
in which the agonist-antagonist activity is synergistic. Physiological 
tremor (e.g., finger tremor) is also 9 to 11 cycles/sec in the adult 
but slower in youngsters, and to my knowledge there is no infor- 
mation as to whether or not it is an alternating or synergistic 
tremor. I do not think anyone has ever subjected "trembling with 
joy" or "shaking with fear" to neuromuscular examination, but I 
would think they are more closely allied to hypothalamically- induced 
shivering than to non- hypothalamically induced pathologic tremor. 
There is, of course, one difference in that shivering accomplishes 
something for the animal (i.e., an increase in heat production with- 
out an increase in external work), whereas the tremors you mention 
seem of little biological value. I would like to add that Dr. Kawamura 
and I have produced alternating tremor by stimulation of a prosen- 
cephalic locus that is anatomically different from those loci whose 
stimulation evoked shivering. Additionally, Dr. Hemingway, Dr. 
George, and I recently completed some experiments that demon- 
strated that reserpine blocks shivering but produces an alternating 
tremor, whereas atropine, which is known to block pathologically 
induced alternating tremor, has no effect on shivering. 
DR. FREEMAN: In other words, you draw a period of distinction 
between pathological tremors which are not related to shivering and 
other physiological tremors? 
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