Rationale for Critical Bands

[Daniel Bowling <danielliubowling@xxxxxxxxx>]

Dear List,

Has anyone considered why humans exhibit critical bands in psycho-acoustical experiments (e.g. masking, loudness summation, detectability of phase changes)? Is the assumption that the origin of critical bands is in the physiology of the cochlea? If so, how is this justified? If critical bands result from overlap/interference of vibrations on the basilar membrane one would expect their bandwidths to change significantly at different sound pressure levels (because more auditory nerve afferents over longer portions of the cochlea are activated by higher SPLs, and fewer afferents within restricted areas of the cochlea are activated by lower SPLs), but this does not seem to be the case.

In vision, attempts to rationalize psychophysical phenomena in terms of retinal physiology have had very limited success.

Any thoughts would be much appreciated.

Thanks,

Dan