FREQUENCY SPACING OF MULTIPLE SPONTANEOUS OTOACOUSTIC EMISSIONS SHOWSRELATION TO CRITICAL BANDS - A LARGE-SCALE CUMULATIVE STUDY

Multiple spontaneous otoacoustic emissions (SOAEs), recorded in one ea r, are not randomly spaced on the frequency scale. Extent and origin o f spacing order, however, are not clear. Therefore, the raw data of al l human SOAE surveys were pooled, and the intervals of all possible em ission pairs in each ear were in total outlined according to size on a distribution diagram (n = 5245, for intervals up to 2/3 octave). Prev alence was increased for intervals between the benchmarks of 1 and 2 c ritical bands (CB). This CB-2CB range was further characterized by pre ference of intervals with low-order frequency ratios like 5:4 or 6:5, whereas outside CB-2CB there were no such effects. The results are dis cussed in the context of current knowledge of the origin of critical b ands. Experiments are proposed that test the hypothesis of an influenc e of the olivocochlear efferents on SOAE spacing. (C) 1997 Elsevier Sc ience B.V.