Temporal Patterning in Speech: The Implications of Temporal Resolution and Signal-Processing

Abstract

There are wide variations in behavioural indices of temporal resolution in humans, with degradation of resolution accompanying both brain damage (Lackner and Teuber 1973), and hearing impairment (Tyler et al. 1982). The presence of only minimal abnormalities of temporal processing in animal models of cochlear pathology (Harrison and Evans 1979; Evans 1984, and papers cited therein) raises some doubt as to whether degradation of temporal resolution is a direct consequence of cochlear pathology, or some loosely associated correlate, or the result of abnormal central neural organisation following the lack of afferent stimulation. While physiological answers are being sought to such questions, it is profitable (i) to develop the ecological description of temporal structure in significant auditory events; (ii) to develop an understanding of the perceptual processes and phenomena resulting from temporal structure; and (iii) to develop ways of transforming that structure which are scientifically and technologically useful. This paper is directed to those three ends. We must remember, however, that the contrast between time- and frequency-based structures is more a dichotomy of our explanatory framework than a dichotomy in the reality we seek to describe.