Central physiological correlates of ageing and presbycusis in mice.
Responses of neurons in the central auditory system of ageing mice suggest several sources of age-related problems in hearing. The central representation of frequency (tonotopic organization) is disrupted in mice with presbycusis, implying a cause of problems with frequency coding. In very old mice with only minimal hearing loss, normal-responding neurons co-exist with "sluggish" neurons, which suggests there is a process of attrition that affects some neurons more than others. Spontaneous activity increases in neurons of older mice, implying a decrease in the physiological signal-to-noise ratio. The effects of age-related hearing loss are more severe in the ventral cochlear nucleus than in the dorsal cochlear nucleus, suggesting that various functional circuits may be more or less vulnerable to presbycusis.
Willott
J F
JF
Department of Psychology, Northern Illinois University, DeKalb.
D000161:Acoustic Stimulation; D000375:Aging / Q000502:physiology*; D000818:Animals; D003056:Cochlear Nerve / Q000503:physiopathology*; D007245:Inferior Colliculi / Q000503:physiopathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009474:Neurons / Q000502:physiology; D011304:Presbycusis / Q000503:physiopathology*