Children's timing and repair strategies for communication in adverse listening conditions

This study investigated the development of clear speech strategies in children. Groups of 20 talkers aged 9-10 and 1314 years were recorded in pairs while they carried out ‘spot the difference’ picture tasks, either while hearing each other normally (‘no barrier’) or when one talker heard the other via a noise vocoder (VOC), which led their interlocutor (‘talker A’) to clarify their speech to maintain effective communication. Data were compared to those previously collected for 20 adults. Mean word duration, number and duration of pauses were calculated for talker A. Strategies used in response to direct requests for clarification were also classified. Children spoke at a slower rate than teens and adults, who did not differ. Relative to ‘no barrier’, all groups significantly reduced their speech rate in VOC and used longer pauses, but the relative change in pause rate across conditions was greater for adults than children or teens. In response to a direct clarification request, children and teens used a higher rate of repetitions than adults who used more varied strategies. These results suggest that although children use some strategies to clarify their speech in difficult conditions, other strategies continue to develop until late adolescence.