In the March/April 2009 edition of Acta Acustica Journal, a research paper by Spanish scientists entitled "Physical Analysis of Several Organic Signals for Human Echolocation: Oral Vacuum Pulses" was published. This research has shown scientifically that human beings can develop echolocation, the system of acoustic signals used by dolphins and bats to explore their surroundings. Producing certain kinds of tongue clicks helps people to identify objects around them without needing to see them, something which would be especially useful for the blind.
In order to learn echo-location, the scientists are developing protocols to allow any person learn this unique ability.
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