The influence of the visual design of spaces on female speakers' vocal effort: an exploratory study

Vocal effort, as defined by Hunter et al, is a subjective perceptual phenomenon influenced by individual and environmental factors. This study investigates the impact of visual room design on vocal effort and measurable vocal demand response, which includes acoustic metrics such as sound pressure level, fundamental frequency (f₀), and cepstral peak prominence. Twenty female participants performed speech tasks in two acoustically identical rooms that differed visually: an undecorated room (Room A) and a visually stimulating, classroom-like room (Room B). Participants reported significantly lower vocal effort on a visual analog scale in Room A compared with Room B (P<0.001), suggesting that visual design can modulate subjective vocal experience. However, acoustic measures of vocal demand response revealed no significant differences between the two environments. These findings reinforce the need to explore multimodal influences on vocal effort, emphasizing the role of visual environments in shaping perceptual experiences of voice use without altering acoustic output. Implications for experimental design and therapeutic interventions are discussed.