Quantifying motor stability in singing and speech production: an investigation in rate and loudness manipulations

Background: Choirs require precise articulation in order for the lyrics to be understood. Maintaining consistent diction in singing and speaking may contribute to motor stability. Previous research shows that there are many factors that impact the stability of speech; however, little research has been done on the stability of singing.

Methods: Nineteen people were recruited for this study, nine experienced singers and ten naïve singers. They each sang and spoke sentences while wearing infrared light-emitting diodes (IREDs). They produced these sentences at baseline and were also told to speak/sing loudly, softly, quickly, and slowly. Both the duration and stability of the productions were analyzed.

Results: The duration of the phrases was shorter under the fast condition and longer under the slow condition for both speaking and singing. Singing had a longer duration than speaking overall. Stability data revealed that speaking loudly was significantly more stable than speaking at baseline. Singing quickly and slowly were both less stable than singing at baseline. There were no significant differences in speaking and singing between the experienced singers and naïve singers.

Conclusion: These results suggest that, in some instances, participants behaved similarly when speaking and singing, whereas some manipulations differentially changed their stability in speaking as opposed to singing. This research is important because it contributes to current knowledge of how common changes in volume or speed can contribute to consistency in singing. This study also provides a valuable contribution to the current body of research and suggests ways in which singing may be an effective treatment for speech and communication disorders.