i6o 



Scientific Proceedings (76). 



in the study of cerebral control of body temperature, 1 is performed 

 aseptically under light ether anesthesia. As soon as the animal 

 is free from the narcotic certain cerebral functions may be in- 

 fluenced by the passage through the tube of hot or cold water. 



The advantages of such a method are (1) the confinement of 

 the effective agent entirely to the cerebrum (or a portion of it), 

 (2) the absence of an anesthetic, and (3) the ease with which the 

 functional activity of the brain can be quickly altered in either 

 of two opposite directions. 



The uterine activity was recorded by air conduction from a 

 finger cot inflated within the rabbit's uterus. Most of the animals 

 used were in early pregnancy. The results obtained by this 

 method show that under a few minutes of cerebral cooling (io° C.) 

 the cavity of the uterus becomes much diminished in volume 

 and there is a tendency to an increase in the amplitude and fre- 

 quency of the individual contractions; on the other hand a change 

 to heating (45 0 C.) soon causes a reversion to original conditions. 

 Although voluntary limb movements are sometimes a disturbing 

 factor we have been able to exclude these entirely as the cause of 

 the changes described. 



There is however no doubt that the changes in volume of the 

 uterine cavity are largely dependent upon changes in tone of the 

 abdominal musculature. One can readily follow with the hand 

 the contraction and relaxation of the recti, for example, which 

 are associated respectively with cooling and heating of the cere- 

 brum. Furthermore the uterine changes were not observed in 

 two curarized animals, nor were they obtainable in an animal 

 with cord completely transected between the sixth and seventh 

 dorsal vertebrae. However, under both of the latter conditions the 

 normal activity of the uterus was very feeble. 



The method of excluding the voluntary abdominal muscles 

 by suspending the intact uterus, surrounded by warm oil, in a 

 cylinder has failed to give very positive evidence of a direct cere- 

 bral control of the uterus. This method has always been pursued 

 under light anesthesia however. In one of six animals there was 

 under cerebral cooling a marked increase in tone which was not 

 diminished by cessation of the cooling process. In another the 



1 Barbour, H. G., Arch. exp. Path. u. Pharm., 1912, 70, 1. 



