Speech intelligibility under various degrees of anoxia

Abstract

"Under standard conditions speech intelligibility is shown to decrease with increasing altitude. If the original sound level is low the decrement in articulation is large, discrete word intelligibility falls percipitately and speech rapidly becomes unintelligible. The effects of anoxia are minimal if sea level articulation is high… . The fact that 67% of the subjects (8 of 12) showed a decrement in performance at 13,600 ft. suggests the importance of using oxygen equipment on long flights even at low altitudes." (PsycInfo Database Record (c) 2025 APA, all rights reserved)