title: Postnatal development of cochlear microphonic and compound action potentials in a precocious species, Chinchilla lanigera.
abstract: The development of sound-evoked responses in Chinchilla lanigera was studied from postnatal ages P0-1 (first 24 h) to adult. Cochlear microphonic (CMs) and compound action potentials (CAPs), representing ensemble sound-evoked activities of hair cells and auditory nerve fibers, respectively, were present as early as age P0-1. The data indicate that CM thresholds and sensitivities were generally adult-like (i.e., fall into adult ranges) at birth, but suprathreshold CM amplitudes remained below adult ranges through P28. CAP thresholds reached adult-like values between P7-P14, but the suprathreshold CAP amplitude continued to increase until ∼P28. The results confirm the auditory precociousness of the chinchilla.
authors.affiliation: Neuroscience Training Program and Department of Physiology and Biophysics, University of Colorado School of Medicine, Aurora, Colorado 80045, USA. Heath.jones@ucdenver.edu
authors.forename: Heath G
authors.initials: HG
authors.lastname: Jones
authors.forename: Kanthaiah
authors.initials: K
authors.lastname: Koka
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Tollin
mesh_terms: D000161:Acoustic Stimulation; D000367:Age Factors; D000375:Aging; D000818:Animals; D001309:Auditory Threshold; D002682:Chinchilla / Q000254:growth & development*; D003051:Cochlea / Q000254:growth & development*; D003055:Cochlear Microphonic Potentials; D003056:Cochlear Nerve / Q000254:growth & development*; D005072:Evoked Potentials, Auditory