Psycho-mnemonic Phenomena 321 



greater or less number of specific or mnemonic potential 

 elements differing from one cell to another. But we 

 must bear in mind that this differentiation is not acquired 

 exclusively after birth, but appears already within cer- 

 tain limits, at least in relation to all the congenital 

 instincts, during ontogeny. 



"We see," writes Hering, "how an entire group of 

 sensations become reproduced with such vividness and 

 in such precise order of space and time that it can 

 deceive us as to its reality. This shows us in a most 

 striking way that even after the sensation and percep- 

 tion in question has long since disappeared, there remains 

 still in our nervous system a material trace, an alteration 

 of the molecular or atomic connections by which the 

 nervous substance is rendered capable of reproducing 

 these physical processes, with which the corresponding 

 psychic process of sensation and perception is also deter- 

 mined." "The representations do not last as representa- 

 tions but what does persist is that particular attunement 

 of the nervous substance, by virtue of which when it 

 is properly struck it sounds again today the same note 

 which it gave forth yesterday." 235 



This conception of Hering of the disposition of the 

 nervous substance to sound again the tone of yesterday 

 is derived from the physical phenomenon of acoustic 

 resonators. The nervous substance which would be made 

 to vibrate in a given specific way at a given point by a 

 definite elementary sensation or representation would re- 

 main from that moment capable of vibrating always and 

 exclusively according to that specific mode. According 

 to the hypothesis of mnemonic elements on the contrary, 



'"Hering : tlber das Gedachtnis etc. P. 8, 9. 



