ROLE OF THE PROSENCEPHALON IN SHIVERING 
inhibit shivering. Now, if these two statements are incorrect, I 
should like to know about it now, before I take this information 
back to the laboratory . 
DR. STUART: In reply toyour second statement, a report of the 
suppression of shivering by heating the anterior hypothalamus is 
not new. It was reported by Magoun and co-workers in 1938, by 
Hemingway and co-workers in 1940, and more recently by Strom 
and co-workers, and Freeman and Davis. Today Ihave reported the 
suppression of shivering during septal, anterior and posterior hy- 
pothalamic stimulation. The suppression during septal stimulation 
and the comparison of stimulus intensities at the three loci is new 
information, but the suppression during electrical stimulation of the 
anterior hypothalamus confirms the previous work of Hemingway, 
Forgrave and Birzis and Andersson, Grant and Larsson. Therefore, 
there is nothing in this work to conflict with your second statement. 
Your first statement that the posterior hypothalamus is blind to 
temperature has no direct relation to these experiments which are 
concerned with localization of neural regions relatedtothe efferent 
(motor) arm of shivering rather than the reception of temperatures. 
However, I would like to comment on your statement to the extent 
that it relates to a neurophysiolgical problem and involves neuro- 
physiological techniques of investigation. The experimental evidence 
on which you base your statement involves, I believe, gradient 
calorimetiy and very accurate measurements of temperature at 
various body sites. Such experiments have obviously been of great 
value, but before accepting the fact that the posterior hypothalamus 
is blind to temperature, I would expect reasonable experimental 
evidence showing that the firing pattern of single hypothalamic 
neurons is reversibly altered by cooling and warming, and evidence 
that such neurons are in the anteriorhypothalamus^and not the pos- 
terior hypothalamus. Since an animal with anterior hypothalamic 
lesions can shiver, it migjitwell be that third or second order skin 
temperature neurons impinge upon posterior hypothalamic neurons 
and that their discharge is capable of instigating and maintaining 
shivering. None of these things have ever been demonstrated and 
they will, I believe, involve microelectrode experimentation. 
DR. FREEMAN: The only evidence that I know that bears direct- 
ly on this is the series of attempts that Davis and I made to heat and 
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