Behavioral assessments of auditory sensitivity in transgenic mice

This report summarizes positive reinforcement conditioning procedures for a ssessing sensory function in transgenic mice. To illustrate these behaviora l methods auditory sensitivity was measured in mice lacking alpha 9 acetylc holine receptor subunits (alpha 9 knock-out mice). These receptors are know n to play an important role in the efferent pathways that modify cochlear r esponses to sound stimuli. The strategies of parameter manipulation that le d these subjects through their preliminary training stages to stable thresh old performances are described in detail. Techniques for estimating and int erpreting sensory thresholds are discussed from the perspective of signal d etection analyses. This study found no significant differences between alph a 9 knock-out mice and control subjects when hearing thresholds were measur ed under quiet conditions, as predicted by previous behavioral and electrop hysiological evidence. (C) 2000 Elsevier Science B.V. All rights reserved.