STUART, D. G. 
EFFECTS OF DECORTICATION ON SHIVERING 
Methods . Removal ofthe cerebral cortex by aseptic surgery was 
performed on 21 cats all under pentobarbital sodium anesthesia (35 
mg/kg I. P.). On the first three post-operative days these animals 
were given injections of Diciystin Fortis and were maintained in a 
25 C environment. 
Figure 2 is a film positive of buffered thionine sections at 
various frontal levels of a decorticate cat brain. It demonstrates 
that in preserving the medial aspects of the anterior heads of the 
caudate nuclei, the septum is preserved, even thou^ the corpus 
callosum is removed (Fig. 2A). Additionally, althougji the fomices 
were removed, direct paleocortical- diencephalic connections still 
existed by virtue of the integrity of the ri^t amygdaloid nucleus 
(Fig. 2B). The thalamus, hypothalamus andmidbrain are undamaged 
by this surgery (Fig. 2C and 2D). 
Immediately prior to and three days after surgery, the resting 
and shivering oxygen consumption rates were determined. One cat 
was tested at3,28and470days after surgery. A mild cooling stress 
induced active and continuous shivering at a rectal temperature of 
36 C to 37 C. This stress consisted of immersing each animal in 
o o 
10 C water for two minutes and 40 C water for one minute. This 
was repeated once and finally the animal was immersed in 10 C 
water for one minute. The rectal temperature of each cat was mon- 
itored during the determination of VO . 
At the conclusion of these tests an attempt was made to keep 
the animals alive for 28 days, but, with the exception of one animal, 
this met with failure. Of the 21 cats on which the decortication was 
performed, 10 livedthree days or longer, 5 lived one week or longer, 
2 lived two weeks or longer, and one animal was sacrificed 570 days 
after surgery. The most frequent cause of death was aspiration of 
vomitus. This was probably caused by undue traumatization of the 
vagus nerve during temporary clamping of the common carotid 
artery. If such traumatization permanently damages afferent fibers 
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