ABSTRACT
The production of fluent speech requires the translation of abstract linguistic units into constantly changing movement sequences of the motor speech subsystems subserving articulation, phonation and respiration. Voice onset time refers to the time lag between the sudden opening of two articulators following a plosive consonant, and the time taken to initiate periodic vocal cord vibration subsequently. Vowel duration refers to the length of time that a vowel remains in a steady state, with the vowel quality remaining consistent and relatively uninfluenced by the sounds preceding and following it. Electromyographic (EMG) activity can be recorded when an impulse travels down an axon and causes a temporary reversal of the polarization, called an action potential, of the cell membrane at each muscle fibre. One way of evaluating the effectiveness of coordinative articulatory systems is by examining the temporal order of movement onsets and peak velocities for combined articulator movements.
