title: Musical experience sharpens human cochlear tuning.
abstract: The mammalian cochlea functions as a filter bank that performs a spectral, Fourier-like decomposition on the acoustic signal. While tuning can be compromised (e.g., broadened with hearing impairment), whether or not human cochlear frequency resolution can be sharpened through experiential factors (e.g., training or learning) has not yet been established. Previous studies have demonstrated sharper psychophysical tuning curves in trained musicians compared to nonmusicians, implying superior peripheral tuning. However, these findings are based on perceptual masking paradigms, and reflect engagement of the entire auditory system rather than cochlear tuning, per se. Here, by directly mapping physiological tuning curves from stimulus frequency otoacoustic emissions (SFOAEs)-cochlear emitted sounds-we show that estimates of human cochlear tuning in a high-frequency cochlear region (4 kHz) is further sharpened (by a factor of 1.5×) in musicians and improves with the number of years of their auditory training. These findings were corroborated by measurements of psychophysical tuning curves (PTCs) derived via simultaneous masking, which similarly showed sharper tuning in musicians. Comparisons between SFOAE and PTCs revealed closer correspondence between physiological and behavioral curves in musicians, indicating that tuning is also more consistent between different levels of auditory processing in trained ears. Our findings demonstrate an experience-dependent enhancement in the resolving power of the cochlear sensory epithelium and the spectral resolution of human hearing and provide a peripheral account for the auditory perceptual benefits observed in musicians. Both local and feedback (e.g., medial olivocochlear efferent) mechanisms are discussed as potential mechanisms for experience-dependent tuning.
authors.affiliation: School of Communication Sciences & Disorders, University of Memphis, Memphis, TN, USA; Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA. Electronic address: g.bidelman@memphis.edu.
authors.forename: Gavin M
authors.initials: GM
authors.lastname: Bidelman
authors.affiliation: School of Communication Sciences & Disorders, University of Memphis, Memphis, TN, USA.
authors.forename: Caitlin
authors.initials: C
authors.lastname: Nelms
authors.affiliation: School of Communication Sciences & Disorders, University of Memphis, Memphis, TN, USA.
authors.forename: Shaum P
authors.initials: SP
authors.lastname: Bhagat
mesh_terms: D000161:Acoustic Stimulation; D000162:Acoustics; D000293:Adolescent; D000328:Adult; D001299:Audiometry; D001309:Auditory Threshold; D003051:Cochlea / Q000502:physiology*; D004848:Epithelium / Q000502:physiology; D005260:Female; D006309:Hearing; D006801:Humans; D008297:Male; D009146:Music; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D010470:Perceptual Masking; D011601:Psychophysics; D013016:Sound; D055815:Young Adult
keywords: Cochlea; Experience-dependent plasticity; Hearing; Musical training; Psychophysics