Echolocation
© MattLphotography/AlamyEcholocation is the ability to sense oneโ€™s surroundings by interpreting how sounds reflect off nearby objects
People who are blind are able to better complete various practical and navigation tasks with the help of echolocation, new research suggests.

Echolocation occurs when an animal emits a sound that bounces off objects in the environment, returning echoes that provide information about the surrounding space.

While the technique is well known in whales and bats, some people who are blind use click-based echolocation to judge spaces and improve their navigation skills.

Lore Thaler at Durham University in the UK and colleagues looked into the factors that determine how people learn this skill.

Over the course of a 10-week training programme, the team investigated how level of vision and age affect the learning of click-based echolocation, and how learning this skill affects the daily life of people who are blind.

Blind and sighted participants aged between 21 and 79 took part in 20 two-to-three-hour training sessions over the study period.

Blind participants also took part in a three-month follow-up survey assessing the effects of the training on their daily life.

The researchers found that people who are blind and those who are sighted improved considerably on all measures, and in some cases performed comparably with expert echolocators at the end of the training.

In the follow-up survey, all participants who were blind reported improved mobility, and 83 per cent reported better independence and well-being. The results are published in the journal PLoS One.

The results suggest the ability to learn click-based echolocation isn't strongly limited by age or level of vision, the researchers say, and this has positive implications for the rehabilitation of people with vision loss or in the early stages of progressive vision loss.

"I cannot think of any other work with blind participants that has had such enthusiastic feedback," said Thaler.

"People who took part in our study reported that the training in click-based echolocation had a positive effect on their mobility, independence and well-being, attesting that the improvements we observed in the lab transcended into positive life benefits outside the lab.

"We are very excited about this and feel that it would make sense to provide information and training in click-based echolocation to people who may still have good functional vision, but who are expected to lose vision later in life because of progressive degenerative eye conditions," said Thaler.

Click-based echolocation is currently not taught as part of mobility training and rehabilitation for people who are blind. Experts say there is a possibility that some people are reluctant to use it due to a perceived stigma around making the required clicks in social environments.

Despite this, the results indicate that people who use echolocation, and people new to echolocation, are confident about using it in social situations, the researchers say.

Journal reference: PLoS One, DOI: 10.1371/journal.pone.0252330