THE NORMAL ACTIVITY OF THE WHITE RAT AT 

 DIFFERENT AGES. 



JAMES ROLLIN SLONAKER. 



{Stanford University, California.) 



With Eight Figures. 



While observing Dr. Watson's experiments to test the abiHty 

 of white rats at different ages to learn new tricks/ it occurred to 

 me that possibly their greater susceptibility to education at a cer- 

 tain age might be due, to some extent at least, to the fact that they 

 were more active at that age than at any other, and that they were 

 thus able to try more avenues of approach to their food in a given 

 time. With this thought in mind, I planned to test their volun- 

 tary activity at different ages to ascertain how the age of greatest 

 activity compared with that at which they were the most capable 

 of education. 



Three preliminary experiments were performed in the Neuro- 

 logical laboratory of the University of Chicago, and other experi- 

 ments are now being carried on in the Physiological laboratories 

 of Stanford University. In this connection I wish to thank Dr. 

 Henry H. Donaldson for his ready cooperation and assistance 

 in providing necessary materials for the apparatus and Dr. 

 Watson for his aid in constructing the apparatus. 



The apparatus employed was very similar to that used by Dr. 

 C. C. Stewart- in his experiments on different animals. Several 

 improvements have been made w^hich will be described in a later 



The apparatus consists of two essential parts: first, the revolvmg 



> Watson, J. B., Animal Education;An Experimental Study on the Psychical De\elopment of 

 the White Rat, Correlated with the Growth of its Nervous System. The University of Chicago Press. 

 1903. 



- Stewart. C. C, Variations in Daily Activity Produced by Alcohol and by Changes in Barometric 

 Pressure and Diet, with a description of Recording Methods. Am. Journ. Physiol., vol. i, pp. 40-56. 



