title: Long-term and short-term characteristics of speech: implications for hearing aid selection for young children.
abstract: This study examined the effects of distance and postural position of both parents and children on the long-term and short-term spectral characteristics of speech produced by the parents. Thirty children (ages 2 months to 3 1/2 years) and their parents (30 mothers and 15 fathers) participated. Third-octave band and overall levels of the long-term average speech spectrum (LTASS) for each speech sample were analyzed in three postural positions and a 1-meter reference condition for each age category. Short-term spectral characteristics of three phonemes (/s/, /integral of/, /t integral of/) also were analyzed. Results show that typical levels at the input to a child's hearing aid microphone may be as much as 20 dB higher than those found in face-to-face adult conversation. Furthermore, the spectral shape may deviate substantially from an idealized version of the LTASS. Results of the short-term analysis reveal that the peak levels of the three selected phonemes often exceed the LTASS by more than the 12 dB that is often quoted to represent the 1% rms levels of speech in relation to the long-term average. Implications of these results for specific hearing losses are discussed.
authors.affiliation: Boys Town National Research Hospital, Omaha, NE.
authors.forename: P G
authors.initials: PG
authors.lastname: Stelmachowicz
authors.forename: A L
authors.initials: AL
authors.lastname: Mace
authors.forename: J G
authors.initials: JG
authors.lastname: Kopun
authors.forename: E
authors.initials: E
authors.lastname: Carney
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000367:Age Factors; D001309:Auditory Threshold; D002675:Child, Preschool; D007758:Ear, Inner / Q000503:physiopathology; D005260:Female; D006309:Hearing; D006310:Hearing Aids; D006319:Hearing Loss, Sensorineural / Q000503:physiopathology / Q000534:rehabilitation; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D010287:Parent-Child Relations; D010700:Phonetics; D011187:Posture; D013060:Speech; D013067:Speech Perception; D014705:Verbal Behavior