Introduction: The objective of the study was to assess how posture and vocal acoustics are modified when one needs to communicate despite environmental obstacles (i.e. vocal effort performance).
Method: 20 healthy young women participated to this study. They had to communicate numbers to a listener. Environmental obstacles were the distance between the subject and the auditor, and the noise. Segmental posture modifications were recorded and analyzed using the numerical infra-red system for movement analysis SMART. Vocal acoustics and electroglottography were also recorded and analyzed using the EVA system.
Results: The study showed the presence of objective postural modifications during vocal effort. Their amplitude increased when the environmental obstacles to communications increased, and they anticipated the vocal production.
Discussion: The vocal effort concept and its relation with the posture, the voice and the subject's feeling are reviewed on the basis of these results. Laryngeal effort is not isolated, but belongs to a global behavioral strategy which aims to improving the efficiency of the communication.