The effect of timing errors on the intelligibility of deaf children's speech

Abstract

At the 93rd meeting of the Acoustical Society of America, we presented a preliminary report on a technique to correct deviant timing errors in deaf children's speech by computer processing of recorded speech samples. Timing modifications were accomplished by direct manipulation of the waveform in which whole pitch periods were deleted from steady‐state portions of speech segments, leaving all other aspects of the speech unchanged. The following six‐stage approximation procedure was used to correct the deviant timing patterns: (1) original, unaltered utterance, (2) correction of pauses only, (3) correction of relative timing (stressed/unstressed ratio), (4) correction of absolute syllable duration, (5) correction of relative timing and pauses, and (6) correction of absolute syllable duration and pauses. This report will present preliminary data on the changes in intelligibility that occurred as a result of the systematic timing corrections Intelligibility measures were obtained by playing the original sentences and the computer‐modified versions to persons not familiar with the speech of the deaf. The measure of intelligibility was the proportion of words correctly understood by the listeners. The data showed that, on the average, intelligibility improved slightly when relative timing errors only were corrected. A decrease in intelligibility was observed for the other forms of timing modification. There were marked individual differences and the correction of deviant timing patterns was relatively more important for improving the intelligibility of some children's speech than others. [Research supported by PHS Grant NS 09252.]