CLARK, G. 
Andersson has reported (1957) that by electrical stimulation of the 
septal region in unanesthetized goats shivering can be easily induced. 
Figure 17 is a diagram of the active points he found. It should be 
reiterated that removal of the septum does not in any way interfere 
with a dog's ability to withstand cold or heat and the body tempera- 
tures of such preparations are within normal range (Keller, 1960). 
The role of the septum in temperature regulation is very difficult 
to visualize but any role at all is not in accord with the dual center 
theory of Ranson. 
Freeman and Davis (1959) have recently reported some results 
obtained by heating or cooling the brain of the cat that are not com- 
patible with the localization of the dual centers as proposed by Ran- 
son. Their results from heatingare shown in Figure 18, which again 
is one of those unfortunate parasagittal projections. Heating in the 
chiasmal region would be expected to bring about a fall in body 
temperature but a fall in body temperature on heating the anterior 
pons and a rise in body temperature on heating the midbrain and 
caudal hypothalamus are not in accord with the dual center hypo- 
thesis. The results with cooling as seen in Figure 19 are even less 
explicable. Cooling should give no response in the chiasmal region 
yet both a rise in some cases and a fall in others was observed. In 
the caudal hypothalamus only falls in bo(fy temperature were ob- 
served to result from coolingandthe points extend well into the mid- 
brain while the only rises in body temperature from posterior 
cooling were in the anterior pons. None of these results are in 
accord with the localization that was proposed for the dual centers 
nor would they be predicted on the basis of results of extirpations. 
This work I have covered maybe summarized as follows: In the 
past two decades, that is, since the dual center theory was thought 
to be validated by exact localization, there has appeared some con- 
firmatory work, none of which was crucial, and there has also 
appeared a body of work not explicable in terms of the localization 
proposed. Furthermore, none of the primary questions neglected by 
Ranson have been answered. 
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