The Function Of Noise In Auditory Signal Transduction

Noise was traditionally regarded as a nuisance, which should be minimized if possible. However, recent research has shown that addition of an appropriate amount of noise can actually improve signal detection in a nonlinear system, an effect called stochastic resonance. While stochastic resonance has been described in a variety of physical and biological systems, its functional significance in human sensory systems remains mostly unexplored, especially in human's hearing system. People study human's hearing system which has about one hundred years. Now we just study hearing system from peripheral to higher neural system in primary phase. The study of single neuron's spike is weak. We need making more progress in this study. This paper mainly research on the experiments of psychological acoustics and physiological acoustics in order to investigate hearing system.In the first chapter, we demonstrate the effect of noise on information process in neural system and hearing system simply, and describe the theory, stochastic resonance, which we use in this paper.In the second chapter, we demonstrate the background of psychophysical experiment and method first. Then we particularly describe the experiment that we proceed, that is to say, when adding Gaussian White noise and the filtering neighborhood of the Gaussian White noise, the human's hearing threshold increase or decrease. We analyse the result we get and draw figures. We prove that stochastic resonance not only happens in the auditory peripheral but also in a higher auditory nerve stage.In the third chapter, we demonstrate the background of physiological experiment, the preparing of the experiment (the shield of noise, pulling the glass micropipette and injection, the anatomization of animals), registering the spike of single auditory nerve cell, analyzing the result of experiment, the difficulty in the experiment and how to deal those difficulty.The last chapter is conclusion.