Vibration of beads placed on the basilar membrane in the basal turn of thecochlea

Interferometric recordings of sound-evoked vibrations in the basal turn and hook regions of the guinea-pig cochlea are used to show that reflective mi crobeads (i) follow the motion of the structures on which they are placed, and (ii) do not affect this motion dramatically. Extrapolating these findin gs to other types of reflective or radioactive material lends support to th e findings of numerous studies of cochlear mechanics. (C) 1999 Acoustical S ociety of America.