Properties and Quantification of Linear and Nonlinear Systems

ABSTRACT

Linear and nonlinear mechanisms are prevalent within the auditory system. Our understanding of these mechanisms requires a knowledge of the properties of both linear and nonlinear systems. In this review, we discuss the properties of these systems and techniques used to quantify them. Linear systems are defined in terms of the properties of homogeneity and superposition. Examples are provided in terms of physical systems such as hearing aids and filters as well as physiologic systems present in the auditory periphery. Nonlinear systems are discussed in terms of their lack of superposition. This is illustrated with a saturating nonlinear system and the generation of distortion products. Finally, five different approaches to characterizing nonlinear systems are discussed. Examples from three techniques are provided for characterizing the nonlinearity associated with the mechanical-to-electrical transduction process in the cochlea.

KEYWORD

Distortion products - homogeneity - superposition - slope

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