Navigation Links
Echolocation
Date:8/29/2013

Biologists at LMU have demonstrated that people can acquire the capacity for echolocation, although it does take time and work.

As blind people can testify, we humans can hear more than one might think. The blind learn to navigate using as guides the echoes of sounds they themselves make. This enables them to sense the locations of walls and corners, for instance: by tapping the ground with a stick or making clicking sounds with the tongue, and analyzing the echoes reflected from nearby surfaces, a blind person can map the relative positions of objects in the vicinity. LMU biologists led by Professor Lutz Wiegrebe of the Department of Neurobiology (Faculty of Biology) have now shown that sighted people can also learn to echolocate objects in space, as they report in the biology journal "Proceedings of the Royal Society B".

Wiegrebe and his team have developed a method for training people in the art of echolocation. With the help of a headset consisting of a microphone and a pair of earphones, experimental subjects can generate patterns of echoes that simulate acoustic reflections in a virtual space: the participants emit vocal clicks, which are picked up by the microphone and passed to a processor that calculates the echoes of a virtual space within milliseconds. The resulting echoes are then played back through the earphones. The trick is that the transformation applied to the input depends on the subject's position in virtual space. So the subject can learn to associate the artificial "echoes" with the distribution of sound-reflecting surfaces in the simulated space.

A dormant skill

"After several weeks of training, the participants in the experiment were able to locate the sources of echoes pretty well. This shows that anyone can learn to analyze the echoes of acoustic signals to obtain information about the space around him. Sighted people have this ability too; they simply don't need to use it in everyday situations," says Lutz Wiegrebe. "Instead, the auditory system actively suppresses the perception of echoes, allowing us to focus on the primary acoustic signal, independently of how the space alters the signals on its way to the ears." This makes it easier to distinguish between different sound sources, allowing us to concentrate on what someone is saying to us, for example. The new study shows, however, that it is possible to functionally invert this suppression of echoes, and learn to use the information they contain for echolocation instead.

In the absence of visual information, we and most other mammals find navigation difficult. So it is not surprising that evolution has endowed many mammalian species with the ability to "read" reflected sound waves. Bats and toothed whales, which orient themselves in space primarily by means of acoustic signals, are the best known.

Wiegrebe and his colleagues are now exploring how the coordination of self-motion and echolocation facilitates sonar-guided orientation and navigation in humans.


'/>"/>

Contact: Luise Dirscherl
dirscherl@lmu.de
49-892-180-2706
Ludwig-Maximilians-Universitt Mnchen
Source:Eurekalert

Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/22/2016)... 2016 http://www.researchandmarkets.com/research/p74whf/global_biometrics ... "Global Biometrics Market in Retail Sector ... --> http://www.researchandmarkets.com/research/p74whf/global_biometrics ) has announced ... Market in Retail Sector 2016-2020" report ... Research and Markets ( http://www.researchandmarkets.com/research/p74whf/global_biometrics ) has ...
(Date:1/20/2016)... , Jan. 20, 2016  Synaptics Incorporated ... human interface solutions, today announced sampling of S1423, ... for wearables and small screen applications including smartwatches, ... printers. Supporting round and rectangular shapes, as well ... excellent performance with moisture on screen, while wearing ...
(Date:1/13/2016)... January 13, 2016 ... addition of the  "India Biometrics Authentication ... Forecast (2015-2020)"  report to their ... has announced the addition of the  ... - Estimation & Forecast (2015-2020)" ...
Breaking Biology News(10 mins):
(Date:2/11/2016)... Germany and GERMANTOWN, Maryland ... ; Frankfurt Prime Standard: QIA) today announced the introduction ... for gene expression profiling, expanding QIAGEN,s portfolio of Sample ... enable researchers to select from over 20,000 human genes ... interactions between genes, cellular phenotypes and disease processes. ...
(Date:2/11/2016)... ... February 11, 2016 , ... ... focused on the development and manufacture of biopharmaceuticals and therapeutics, announces an ... the 2016 BioProcess International Awards – Recognizing Excellence in the People, Organizations ...
(Date:2/11/2016)... ... February 11, 2016 , ... ... than 150 years, continues today to pursue the highest level of accuracy and ... instruments: the AR9 Refractometer and the AR5 Refractometer. Accurate, reliable and tough ...
(Date:2/10/2016)... WASHINGTON , February 10, 2016 Early-career ... , Peru , Uganda ... their life-enhancing work in health and nutrition   Indonesia ... Uganda and Yemen are ... sciences and epidemiology. They are also celebrated for mentoring young women scientists ...
Breaking Biology Technology: