A pair of
researchers with Ludwig-Maximilians-Universität München in Germany has found
that echolocation in humans involves more than just the ears. This research
describes how echolocation is thought to work in humans as compared to other
animals, and the results of a study they conducted using volunteers and a
virtual reality system. Echolocation is a means of determining the location of
an object in the near vicinity by emitting sounds and then listening to the
echoes that are bounced off objects when they come back. Bats are perhaps most
famous for their echolocation abilities but many other animals have some degree
of ability as well, including humans. Researchers note that several studies
have been conducted recently to discover just how well humans can use sounds as
a means of navigating terrain when they are unable to see. Thus far, they also
note, none of the studies conducted to date have been able to quantify such an
ability, which tends to muddy the results. In their study, they sought to do
just that.
To find out how
good people are at echolocation and what parts of the body are involved, they
enlisted the assistance of eight sighted students—each was asked to wear a
blindfold and to make clicking noises as they made their way through a long
corridor. Over several weeks' time, each learned to differentiate between
sounds that were echoed back to them, which allowed them to gauge wall distance
and eventually to walk easily through the corridor with no other assistance. Once
they'd mastered the real corridor, each of the volunteers was asked to sit at a
VR workstation that simulated a walk through the same corridor and to use the
same clicks they'd used earlier. In the simulation, the researchers varied the
experience. They found that the volunteers lost most of their echolocation
abilities when they were restricted from movement—they ran into walls that were
easily avoided when allowed to move freely. By moving echolocation to a
simulated environment, the researchers believe that they have finally found a
way to quantify echolocation ability in humans.
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