14th International Congress of Phonetic Sciences (ICPhS-14)
San Francisco, CA, USA
Five kindergarten children who lateralized /s/ were recorded as they imitated sentences with /s/ embedded in various phonetic contexts. They were rerecorded using identical stimuli in ninth or tenth grade of high school. Their /s/ productions were extracted from contexts in which /i, u, œ, _, k, l/ followed /s/. Noise spectrum parameters: mean, standard deviation, skew, and kurtosis, were computed, as were four 3-point rating scale estimates of spectral fitness: 1) number, and 2) frequency of spectral peaks, 3) low frequency energy, and 4) compactness of spectral bandwidth. All subjects exhibited spectral evidence of lateralization; four improved with age by 4-47% more satisfactory measurements, and one declined in satisfactory measures by 13%. The speech pathologists who tested the high school students observed that all displayed oral gestures indicative of lateralization, and four blatantly lateralized. The most perceptually normal subject ended with 79% of spectral profile noise measures satisfactory as versus 85% for normals. Clinical implications are discussed.
Bibliographic reference. Stephens, M. Irene / Lu, F. Ling / Kao, Kuen / Kahvazadeh, Linda / Daniloff, Ray (1999): "Fishing for the past: remanents of early lateralization of [s]", In ICPhS-14, 819-821.