Understanding the impact of early-onset and late-onset vision loss on the perception of sound source distances is crucial. People with vision loss rely heavily on their other senses for path planning, safe navigation, avoiding collisions, and general activities of daily living.
New research from Anglia Ruskin University (ARU) and the University of East Anglia (UEA) reveals that those experiencing partial vision loss in early childhood struggle more with accurately judging sound location compared to those losing sight later in life.
Published in the journal Optometry and Vision Sciences, this pioneering study is the first to compare the distance judgment of sound in individuals with early (before age 10) and later onset vision loss.
The research involved 52 participants aged under 33. Each participant completed 480 trials, estimating the distance of various sounds emitted from distances ranging from 1.2 meters to 13.8 meters away, including speech, music, and noise. Each participant took part in 480 trials over an hour and 40 minutes.
The difference in distance estimations was more pronounced for individuals with early and late onset vision loss when compared to a fully-sighted control group, particularly for nearby distances rather than distant sounds.
Individuals with early-onset vision loss were inclined to perceive sounds played from short distances, up to five meters, as originating from a greater distance, as opposed to the control group.
There were no significant differences in distance judgments between the control group and individuals with late-onset vision loss.
“These results suggest that people who suffer vision loss at birth or in early childhood are more likely to struggle to accurately judge the distance of close-range sounds,” said lead author Professor Shahina Pardhan, Director of the Vision and Eye Research Institute at Anglia Ruskin University (ARU).
“This is the first study of its kind and is important when assessing the healthcare needs of people who suffered partial vision loss early in life, such as at birth or in childhood, who tend to be reliant on their other sensory abilities. Clearly, difficulty in judging short- and medium-distance sounds could have safety implications, such as when attempting to cross the road. Hopefully, this study will add to evidence that will lead to solutions to improve the lives of people with vision loss across the world.”
“Many studies have shown that fully blind people display measurable changes in their hearing abilities, showing either better or worse performance compared to sighted people depending on the hearing task they are given,” Co-author Dr Andrew Kolarik said. “This study shows that even partial vision losses can lead to changes in hearing abilities, especially if vision is lost early on in life.”
Journal reference:
- Shahina Pardhan, Rajiv Raman, Brian C. J. Moore, Silvia Cirstea, Saranya Velu, Andrew J. Kolarik. Effect of early versus late onset of partial visual loss on judgments of auditory distance. Optometry and Vision Science, 2024; DOI: 10.1097/OPX.0000000000002125