A functional model of peripheral auditory system in speech processing

Peripheral auditory system model consists of several parts : the first one being representative of the middle-ear whereas the last one takes place at the first neuron level of the auditory nerve. Experimental data from basilar membrane motion and auditive nerve fiber activity for sinusoidal and click stimuli have been used to define the transfer function of each part. A digital simulation of this model and an analog construction have been investigated and are discussed here. This model reproduces, with a good approximation, the harmonic and transient behavior of the peripheral auditory system and allows one to study the transmission of acoustical information towards the higher-level brain centers. Thus, the temporal pattern of basilar membrane motion during speech perception and the kind of frequency analysis occurring at the level of the first neuron layers is explained by the model.