Research led by Hideko Heidi Nakajima, MD, PhD, featuring members of the Nakajima Ear Mechanics Lab Stefan Raufer, PhD, and John J. Guinan, PhD, reveals newly discovered mechanics in human hearing. Published June 24 in PNAS, the study calls into question the classic view that cochlear mechanics are similar in most mammals. Basic properties of hearing such as its sensitivity and frequency tuning arise from the mechanical responses in the cochlea. Such responses have been measured extensively in the cochlear base of laboratory mammals, and our understanding of human cochlear mechanics is largely founded on the assumption that cochlear mechanics is similar in all mammals.
In this study, the researchers show that the anatomy and motion of the human cochlear partition differ in crucial ways from the generalized classic view of mammalian cochlear mechanics. The results are important for understanding human hearing and for comparison with results from laboratory animals.