Page:The American Journal of Psychology Volume 1.djvu/24

 18

LOMBARD :

M.M

March 29th, 10.00 P. M.

which the reinforcements caused by clinching the teeth were compared with knee-jerks obtained dur- Pi gg 2. i n & rest > are shown in

Fig. 2. Had a still more active form of reenf orce- ment been employed, probably still greater differences would have been seen. The reen- forced knee-jerks, which resulted from volunta- rily clinching the teeth, were so extensive as to convince us that the unknown sources of re- continually influencing the knee-jerk, were com- paratively weak phe- nomena.
 * enforcement, which were

Aim of Experiments of Series I. — It was a great temptation to us to immediately begin to study the effects of different methods of reenforcing the knee-jerk, but we resisted the impulse, know- ing that it was much more important to lay a sure foundation for such work by patient and care- ful study of the extent of the normal knee-jerk when not subject to such exciting influences. We, there- fore, determined to make a series of experiments which should last over many days, and which should determine the extent of the knee-jerk in the case of one man who was well, and who was leading his usual regular life. We could not help hoping that in