Dr. Mel Goodale from University of Western Ontario
Visual” Activity in the Blind Brain: Neural Underpinnings of Echolocation in the Blind
“I can hear a building over there”
Everybody has heard about echolocation in bats and dolphins. These creatures emit bursts of sounds and listen to the echoes that bounce back to detect objects in their environment. What is less well known is that people can echolocate, too. In fact, there are blind people who have learned to make clicks with their mouth and tongue – and to use to use the returning echoes from those clicks to sense their surroundings. Some of these people are so adept at echolocation that they can use this skill to go mountain biking, play basketball, or navigate through unfamiliar buildings. In this talk, we will learn about several of these echolocators – some of whom train other blind people to use this amazing skill.
Testing in our laboratory has revealed that, by listening to the echoes, blind echolocation experts can sense remarkably small differences in the location of potential obstacles. They can also perceive the size and shape of objects, and even the material properties of those objects – just by listening to the reflected echoes from mouth clicks. It is clear that echolocation enables blind people to do things that are otherwise thought to be impossible without vision, providing them with a high degree of independence in their daily lives.
Using neuroimaging (functional magnetic resonance imaging or fMRI), we have also shown that the echoes activate brain regions in the blind echolocators that would normally support vision in the sighted brain. In contrast, the brain areas that process auditory information are not particularly interested in these faint echoes. This work is shedding new light on just how plastic the human brain really is.
For more information about echolocation, see:
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0020162
http://www.uwo.ca/bmi/news/bmi_news/bat_man.html
http://motherboard.vice.com/read/what-its-like-for-someone-whos-blind-to-see-by-echolocation
Reception to follow in PAS (3005) Lounge