Subject: Re: Implicit human echolocation From: Harry Erwin <harry.erwin@xxxxxxxx> Date: Thu, 31 May 2007 08:50:37 +0100 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>The phenomenon is known as facial vision. Dr. Lawrence Scadden could do it well enough to ride a bicycle in traffic despite his total blindness. He was a participant in at least one published study. Most people who use it use passive echolocation as schools for the blind discouraged their students in the past from making echolocation sounds. Humans can also use active echolocation, but not with the range accuracy of bats. I've used passive echolocation. Sighted humans are about as accurate as bats in azimuth and elevation. It's effortful. Once you've memorised your environment, you prefer to operate by dead reckoning, which means you don't notice changes unless they're obvious. This phenomenon is also seen in bats and rodents, and Don Griffin discussed it in Listening in the Dark. -- Harry Erwin, PhD, Senior Lecturer of Computing, University of Sunderland. Computational neuroethologist: http://scat-he-g4.sunderland.ac.uk/~harryerw/phpwiki/index.php/ AuditoryResearch