This paper aims to quantify the evolution of voice fundamental frequency and the slowing down of the speech tempo of 3 divers during the simulated dive HYDRA X at COMEX (Marseille, Nov-Dec 92). The average voice fundamental frequency which is higher in hyperbaric conditions than in free atmosphere conditions appears to be unrelated to breathing mixtures. The higher fundamental frequency shows a steady decrease along the saturation dive. Our study highlights a good stability of pitch frequency for the 2 divers who are in good condition and a bad stability for the other diver who lacks calmness and self confidence. The slowing down of the speech tempo is very important (20% to 40%) during the first week of the dive, then the tempo steadily increases toward a standard value. The data related to the speech tempo is difficult to explain. One can think that it is correlated with some difficulties to breathe and to behavioural problems for the divers. The evolution of pitch frequency during the dive can also be related to psychological and behavioural problems.
Bibliographic reference. Caminero-Gil, M. GuittonF. Javier / Crestel, Joel / Charonnat, Laure (1995): "Pitch and elocution rate of diverts speech", In EUROSPEECH-1995, 2035-2038.