MEASUREMENT OF GUINEA-PIG BASILAR-MEMBRANE USING COMPUTER-AIDED 3-DIMENSIONAL RECONSTRUCTION SYSTEM

Cochleas are known to have the ability to analyze a frequency widely, and this ability seems to be owed mostly to the basilar membrane (BM) configuration. However, the relationship between the cochlear frequenc y-position map and the BM configuration is not clear. Therefore, in th is paper, the internal structures of a guinea pig cochlea, especially the BM configuration, were reconstructed and measured using a computer -aided three-dimensional (3-D) reconstruction system. Then, an attempt was made to examine the influence of the BM configuration on the coch lear frequency-position map. The measurement results indicate that the width of the BM increased and its thickness decreased with an increas e in the distance from the basal turn towards the apical turn. Theoret ical consideration reveals that the wide frequency-position of the coc hlea is achieved by not only the BM configuration change along the len gth of the cochlea but also the change of the Young's modulus of the B M along the length of the cochlea. (C) 1998 Elsevier Science B.V. All rights reserved.