posted on 2022-02-23, 18:33authored byValerie Hazan, Outi Tuomainen, Michèle Pettinato
Purpose: This study investigated the acoustic characteristics
of spontaneous speech by talkers aged 9–14 years and their
ability to adapt these characteristics to maintain effective
communication when intelligibility was artificially degraded
for their interlocutor.
Method: Recordings were made for 96 children (50 female
participants, 46 male participants) engaged in a problem-solving task with a same-sex friend; recordings for 20 adults
were used as reference. The task was carried out in good
listening conditions (normal transmission) and in degraded
transmission conditions. Articulation rate, median fundamental
frequency (f0), f0 range, and relative energy in the 1- to 3-kHz
range were analyzed.
Results: With increasing age, children significantly reduced
their median f0 and f0 range, became faster talkers, and
reduced their mid-frequency energy in spontaneous speech.
Children produced similar clear speech adaptations (in
degraded transmission conditions) as adults, but only children
aged 11–14 years increased their f0 range, an unhelpful
strategy not transmitted via the vocoder. Changes made by
children were consistent with a general increase in vocal effort.
Conclusion: Further developments in speech production
take place during later childhood. Children use clear speech
strategies to benefit an interlocutor facing intelligibility
problems but may not be able to attune these strategies
to the same degree as adults.
This work was supported by the Economic and Social Research Council, Grant RES-062-23-3106 (awarded to Valerie Hazan).