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BELL SYSTEM TECHNICAL JOURNAL 



In the "telephone" theory, as expounded by Voltalini, Rutherford, 

 Waller and others, it is assumed that the basilar membrane vibrates 

 as a whole like the diaphragm of a telephone receiver, and conse- 

 quently responds to all frequencies with varying degress of amplitude. 

 The discrimination of pitch takes place in the brain. 



Meyers in his theory states that various lengths of the basilar 

 membrane are set in motion depending upon the intensity of the 

 stimulating tone. As in the previous theory, the pitch discrimina- 

 tion is accomplished in some way in the brain. 



In the "non-resonant" theory of Emile ter Kuile it is assumed 

 that the sound disturbance penetrates different distances into the 



Diagrammatic representation of auditory function 



Fig. 11 



cochlea depending upon the frequency of the stimulating tone. The 

 further along the membrane the disturbance reaches, the lower will 

 be the pitch sensation. A low pitch tone then stimulates all of the 

 nerve fibres that would be stimulated by tones of higher pitch plus 

 some additional nerve fibres. 



