New Delhi, Jul 20 (IANS): Children who partially lose vision before age 10 may be at risk of developing hearing issues, according to a study led by an international team, including from India.

Researchers from Sankara Nethralaya Eye Hospital in Chennai included 52 participants under 33 years old, who took part in 480 separate trials.

In the trial, they were exposed to sounds that were emitted from distances ranging from 1.2m to 13.8m away and also varied between speech, music, or noise.

Participants had to estimate the distance the sound came from.

The results showed that children who experience partial vision loss found it more difficult to accurately judge the location of a sound than those who lose sight later in life

They tended to judge that sounds played from close distances, up to five metres, were actually coming from further away.

This, the researchers said, may impact their general day-to-day living while path planning, safe navigation, and avoiding collisions.

Further, the team found that distance judgments were not found to be significantly different between the control group and those with late-onset vision loss.

The study, published in the journal Optometry and Vision Sciences, is the first to compare how people with early (before the age of 10) and later onset vision loss judge the distance of sound, said lead author Professor Shahina Pardhan, Director of the Vision and Eye Research Institute at Anglia Ruskin University (ARU).

She noted that the findings can help 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".

"This study shows that even partial vision losses can lead to changes in hearing abilities, especially if vision is lost early on in life," added Andrew Kolarik, of the University of East Anglia's School of Psychology.