THE WHITE RAT AND THE MAZE PROBLEM 155 



period in Experiment II, and some slight evidence of the same 

 thing in Experiment I. (See curves Fig. 1 and 2). 



The only interpretation 1 can offer is this: It was the result 

 of the changing sensory control. The initial control was dom- 

 inantly olfactory: but with repeated trials the kinaesthetic 

 experience grew and strengthened and finally began to come 

 into its own. The running became easy and rapid and the 

 accuracy was becoming habitual. Attention, now being released 

 from the control of the movement, was free to be attracted by 

 the olfactory trail in the cut de sacs and errors became more 

 frequent. The final elimination may have been, and probably 

 was, a relearning with kinaesthesis more firmly established. But 

 besides accuracy there is also speed to consider. 



The conditions of the two experiments give results which 

 differ radically here. As compared with the normal maze, 

 Experiment 1 showed slow initial speed and quick final. Ex- 

 periment II showed quick initial speed and slow final. Let us 

 first discuss Experiment II. 



There is no need to take much time here to discuss the speed 

 in Experiment II. The true path resembled that of the normal 

 maze and the beginning speed was comparable. The slower 

 final speed was a result of the increase of errors. The variable 

 curve seen in Fig. 3 has the same explanation. But let us turn 

 to Experiment 1, where the facts are better seen. 



Olfaction has two uses. First it functions as a distance sense. 

 The reaction in this case is always running — toward food, away 

 from danger. The second function is associated with food- 

 taking. Olfaction is so intimately associated with food-taking 

 that, in man, taste and smell are difficult to disassociate. The 

 point which is here to be emphasized is that when the second 

 of these functions is set up in animals in connection with food it 

 inhibits the first. It seems probable that olfaction furnishes 

 animals with a more accurate criterion of distance than it fur- 

 nishes man and that the nearness of food, with the consequent 

 increased intensity, is the stimulus for the food-taking reaction 

 and the running ceases or slows up. The one response is antici- 

 patory, as Sherrington says, 10 the other consummatory. The one 

 is a somatic reaction, involving the whole body, the other is 

 visceral and confined to certain organs and segments. 



10 Sherrington, C. S. Integrative action of the nervous system. 



