The main goal of this study was to investigate how visual impairment affects speech intelligibility in noisy environments, comparing individuals with normal hearing and those with presbycusis using bilateral hearing aids. Participants underwent an audiovisual FraMatrix test under different visual acuity conditions. The study found a significant reduction in audiovisual intelligibility in noise as visual acuity worsened. These findings underscore the importance of addressing both hearing and vision impairments in clinical practice to enhance patient well-being and reduce social isolation
The reality of sound propagation outdoors is more complicated than simple geometrical spreading above a flat hard ground. Most common grounds, such as grass covered ground and layers of snow, are acoustically soft. This implies a complex reflection coefficient leading to a measured spectrum that is strongly influenced by the type of ground surface between source and receiver. Grounds may not be flat, leading to shadow zones or alternatively multiple reflections at the ground. Gradients of wind and temperature refract sound either upwards (upwind or in a temperature lapse) or downwards (downwind or in a temperature inversion), also leading to shadow zones or multiple reflections, respectively. Atmospheric turbulence causes fluctuations and scatters sound into acoustical shadow zones. Many of these features mutually interact and accurate predictions of sound transmission from source to receiver must somehow account for all of these phenomena simultaneously. Thus for example, ISO 9613 Part 2 in wide use today, attempts to account for all the phenomena empirically. In recent years the application of numerical techniques has led to significant advances. This plenary will review the various phenomena. Emphasis will be put on field measurements and simple physical interpretations. In a few cases, the predictions of ISO 9613 Part 2 will be compared with physical or numerical models
Updated regulations, improved noise reduction, and increased use of hearing protective devices (HPDs) may result in better hearing for noise-exposed workers. In a retrospective longitudinal (1980-2015) cohort study, we conducted a secondary analysis of a database of annual hearing tests from noise-exposed workers aged 20-55 years old. Sample size per cohort ranged from n=1386 to n=5165. No clinically-meaningful cohort differences in thresholds of 5 dB or greater were found for 20- or 30-year olds. For 45- and 55-year olds, later-born cohorts had better thresholds than earlier-born cohorts. Prevalence of hearing loss decreased for later-born cohorts for 30, 45, and 55-year olds. Twenty-year olds in later cohorts were more likely to use HPD than those in earlier cohorts. The lower prevalence of hearing loss and better thresholds in these noise-exposed workers may be due to increased HPD use, changes in workplace regulations, improved workplace noise control, or changed attitudes towards recreational noise exposure.
