Ralph N. Ohde
Div. of Hear. and Speech Sci., Box 552, Station 17, Vanderbilt Univ. School of Medicine, Nashville, TN 37232-8700
During production, there are frequent abrupt changes in the amplitude or
in the spectrum of the sound, and these variations are regarded as boundaries
between speech sounds. The information appears rich in cues for phonetic
features of the segments occurring within 10 to 30 ms of the acoustic
boundaries. Recent research examining children's speech shows that the
information contained within the acoustic boundaries of their productions
provides important cues for consonant place of articulation. In addition,
interspeaker variability for these segments is low, as compared to properties
such as formant transitions. Current studies also reveal that for both adult
and child speech a principal mechanism involved in processing acoustic boundary
cues involves short-term memory, and that the elimination of boundary
information negatively affects perception of place of articulation,
particularly for children's speech. Furthermore, the importance of acoustic
boundaries in children's speech extends to their perception of place of
articulation of both consonants and vowels. Young children accurately process
place of articulation from very short duration stimuli, which includes the
period of rapid spectrum change. In the current paper, this evidence supporting
the salience of acoustic boundary information in children's speech and
children's perception of speech will be presented. [Work supported by NIH,
DC00464.]