ABSTRACT
There is a growing literature on the anatomical changes in the central auditory system that accompany the aging process in the CBA/CaJ mouse, which, as described in Chapter 24, helps us understand in some measure age-related changes in auditory function, particularly the important changes in temporal acuity seen in the physiological studies that they summarize. Here we examine temporal processing in the behavioral correlates of aging, referring back where possible to certain of these anatomical and physiological effects. The subjects are CBA/CaJ mice, and also F1 hybrid mice from a C57BL/6J x CBA/CaJ cross. Both strains retain their threshold sensitivity across the spectrum until well into their second year of life, and thus provide a picture of the relatively pure effects of age on behaviors that depend on auditory processing. The history and rationale for the reflex methods used in these experiments and the procedures common to this work are given in Chapter 5. All experiments measured the acoustic startle response (ASR), as elicited by relatively intense stimuli and modified by relatively weak preliminary stimuli. This chapter addresses the question of how age affects behaviors that depend on the ability to resolve brief perturbations in the acoustic environment.
