A SPECULATION ABOUT THE PARALLEL EAR ASYMMETRIES AND SEX-DIFFERENCES IN HEARING SENSITIVITY AND OTOACOUSTIC EMISSIONS

Hearing sensitivity and the prevalence of spontaneous otoacoustic emis sions show parallel ear and sex differences in humans. Here it is prop osed that these lateral asymmetries and sex differences may all result from differences in the 'strength' of the efferent inhibition deliver ed to individual cochleas. Specifically, it is proposed that the amoun t of efferent inhibition is relatively less in right ears and in femal es than in left ears and males. While it is unclear why or how ear asy mmetries or sex differences would develop in the efferent system, by a ssuming that they do, one can begin to explain a number of basic facts of hearing. It is even possible that the lateral asymmetry in the eff erent system may be related to the well-known cortical asymmetries tha t are believed to underlie speech perception, speech production, and o ther human abilities.