Eponymy, obscurity, Twitmyer, and Pavlov.

The discovery of the conditioned reflex is generally credited to Ivan P. Pavlov. So closely is Pavlov associated with this phenomenon that it is commonly referred to as the Pavlovian conditioned reflex. Edwin B. Twitmyer independently discovered the conditioned reflex at approximately the same time and reported the finding in 1904 at the meeting of the American Psychological Association. Unlike Pavlov's, Twitmyer's data had little impact on psychology. There have been various hypotheses to explain the failure of the field to recognize Twitmyer's discovery. These explanations are criticized and modified to reflect an emphasis on Twitmyer's and Pavlov's respective social and intellectual contexts.