APPLICATION OF NONLINEAR METHODS FOR ANALYZING RATE OF SPEECH PRODUCTION

This pilot study has examined the rate of repetitive speech production through use of nonlinear methods. Durational measures were obtained f rom a normal subject who was required to produce a stimulus word in fo ur speaking conditions: normal, controlled-normal, accelerated, and co ntrolled-accelerated. Phase plots and accumulated time series plots we re utilized to display intra-subject variability. Attractors were obse rved in each of the four phase plots and of particular interest was th e direction of their shift for the different speaking conditions. The accumulated time series plots also revealed patterns of intra-subject variability across time. In summary, these two forms of nonlinear repr esentation successfully characterized qualitative changes within, and across, the four speaking conditions. The observed spectral distributi ons and patterns of variability have implications for differentiating normal from abnormal speaking conditions. (C) 1997 Elsevier Science In c.