V. 



INTERPRETATION OF RESULTS 



Now that the experimental results have been presented there 

 remains the important task of ascertaining, as far as we can 

 do so, the relative scope and value of the different factors in- 

 volved. In making this interpretation and evaluation the dif- 

 ferent theories that have been advanced by the various investi- 

 gators to account for the experimental results previously reported 

 will be discussed. The following questions set forth the chief 

 points of discussion: i) How can association be accounted for 

 when the two terms to be associated are presented with a certain 

 time interval between them? 2) How can association be made 

 when the two terms are presented in the reverse order? 3) Is 

 the simultaneous mode of presentation superior to the successive? 

 These questions are considered below in the order given. 



i. The nature of the connection established between the two 

 members of a pair of external stimuli, the first member of which 

 is presented for a definite time and is succeeded by the second 

 after a definite interval, is the problem to the solution of which 

 the numerous experimental investigations, beginning with Eb- 

 binghaus and continuing through the past 25 years, have aimed 

 to contribute. Thus far, three theories have been advanced for 

 the explanation of this phenomenon, i) One may assume the 

 survival of a memory image of the first member of a pair of 

 stimuli during the time interval which separated it from the 

 second stimuli. The second term of the association, then, coin- 

 cides in time with the "gradually-dying-away" memory image 

 of the first, and it is due to this simultaneity that the association 

 is formed. 2) The connection between the stimuli may be me- 

 diated by some third factor which is not only common to the two 

 stimuli, but is also present during the interval which separates 

 them. For example, a series of syllables may be more success- 

 fully memorized by associating each syllable with its position in 



