A PHENOMENOLOGICAL CHARACTERISTIC 

 OF THE AUDITORY STIMULUS 



FRANK KODMAN, JR., Ph.D. 

 University of Kentucky 



Audition and vision constitute our two most important distance 

 senses. Through these sensory modalities we receive advance not- 

 ice of our physical environment before we actually come in contact 

 with it. Despite the fact that light and sound may be conceptualized 

 by wave theory, there are fundamental and significant differences 

 between them psychophysical^. To amplify this point, several com- 

 parisons are offered. Whereas the wavelength of audible sound may 

 be measured in inches or feet, the wavelength of the visual stimulus 

 is measured in millimicrons. Whereas, under certain conditions, the 

 auditory system can analyze a complex sound into its component har- 

 monics, the visual system cannot distinguish between the wavelengths 

 of reflected light from an object even when all the visible wavelengths 

 are present. This paper will call attention to a heretofore unspecified 

 phenomenological difference between visual and auditory perception 

 and offer a tentative explanation for it. 



The Phenomenon 



Aside from basic differences and similarities between vision and 

 audition, one notes the comparative ease with which the observer per- 

 ceives rotation or inversion of a visual object in space. When we at- 

 tempt to find a comparable example in audition, we are unsuccessful. 

 Although the auditory modality gives us information about distance, 

 stimulus composition and the location of sound sources, it seems that 

 we cannot perceptually invert a sound. To state the case in a different 

 way, we are unable to invert sound emanating from space. Is this 

 sound inversion phenomenon an impossibility due to the physical 

 properties of sound? Is it due to the structure and function of the 

 cochlear mechanism or can it be attributed to an inability of the CNS 

 to mirror certain properties of sound? These are some of the possi- 

 bilities which arise. 



Comparative Stimulus Characteristics 



The physical energy necessary for visual perception is a form of 

 energy described as radiant energy or electromagnetic radiations. 

 These energy particles or photons travel at approximately 186,000 



