Navigation Links
'Blind' Man Navigates Obstacle Course Without Error
Date:12/22/2008

Researchers say finding suggests alternate vision routes in the brain

MONDAY, Dec. 22 (HealthDay News) -- Call it a case of second sight: Scientists report that a blind man in Switzerland was able to make his way through a maze, even though he has no conscious sensation of seeing the world around him.

This phenomenon is an indication that the human brain has ways of processing vision beyond those that are currently understood, the scientists said.

Visual skills include mechanisms "for orienting and doing in the world rather than for understanding," study lead author Beatrice de Gelder, a researcher at Tilburg University in the Netherlands and Harvard Medical School, said in a news release.

Scientists were already aware of a phenomenon called "blindsight," in which the sightless show the ability to sense things around them. In the case of the man profiled in the new study, for example, he can sense facial expressions, and his brain shows signs of reacting to the emotions shown on the faces of others.

But the study authors said the man also has a skill not seen before in the blind -- the ability to navigate a maze, in this case a series of boxes and chairs placed in his way.

The man, whose age and name were not disclosed, suffered two strokes that damaged the visual centers of his brain. He can't see, and brain scans show no signs of activity in the visual centers, the study authors said.

The researchers wrote that the man walks like a blind man and only gets around with the assistance of another person or a cane.

Still, as the study authors reported in the Dec. 23 issue of the journal Current Biology, the man was able to navigate the maze without any problem and didn't require the help of an assistant who stood by in case he stumbled.

The researchers said it's possible, though unlikely, that the man used sound waves to detect the location of the obstacles.

Colin Ellard, associate chair of the department of psychology at the University of Waterloo in Canada, said the study findings reflect previous research that suggests the comprehension of vision isn't limited to one part of the brain.

The study "is useful in the sense that it adds to a larger story about how vision is organized in the brain," Ellard said. "The take-home message would be that our ability to 'see' consists of a constellation of different types of abilities. Some can help us to understand, think and talk about what is in the external world, but others act to help us organize movements such as reaching or walking to targets. This study highlights the fact that these different abilities depend on different parts of our brain."

More information

Learn more about blindsight from Bryn Mawr University.



SOURCES: Colin Ellard, Ph.D., associate chair, department of psychology, University of Waterloo, Ontario, Canada; Dec. 23, 2008, Current Biology


'/>"/>
Copyright©2008 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. Can brain-injured, partially-blind stroke patients regain some of their lost vision?
2. New discovery may improve treatment of one of the worlds leading causes of blindness
3. Verizon Awards $1.5 Million Grant to Expand American Foundation for the Blinds Web Site for Seniors With Age-Related Vision Loss
4. Blinded by the Light? Vision Problems and Visual Discomfort Make Driving in the Dark Difficult, Uncomfortable for Most Americans
5. Diabetes: A Top Cause of Blindness Among Adults
6. Survey Confirms Americans Have a True Blind Spot Regarding Their Eye Health - and the Real Danger of UV Rays
7. STEP HIV vaccine study to be unblinded
8. Gene therapy safety trial for childhood blindness under way
9. National Federation of the Blind to Award $100,000
10. Blind humans lacking rods and cones retain normal responses to non-visual effects of light
11. Champion of blinded soldiers, Congressman Murtha, is Man of Vision
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/27/2016)... ... June 27, 2016 , ... ... its strategic partnership with Connance, a healthcare industry leader providing predictive analytics ... proprietary technology combine to provide health systems, hospitals and ambulatory surgical centers ...
(Date:6/26/2016)... ... June 26, 2016 , ... Pixel Film Studios Released ProSlice ... "Film editors can give their videos a whole new perspective by using the ... of Pixel Film Studios. , ProSlice Levels contains over 30 Different presets to ...
(Date:6/25/2016)... ... June 25, 2016 , ... Austin residents seeking Mohs ... College of Mohs Surgery and to Dr. Russell Peckham for medical and surgical dermatology. ... treatment for skin cancer. The selective fellowship in Mohs Micrographic Surgery completed by Dr. ...
(Date:6/25/2016)... ... 25, 2016 , ... Dr. Calvin Johnson has dedicated his ... implemented orthobiologic procedures as a method for treating his patients. The procedure is ... to perform the treatment. Orthobiologics are substances that orthopaedic surgeons use to help ...
(Date:6/24/2016)... ... 24, 2016 , ... June 19, 2016 is World Sickle Cell Observance Day. ... the benefits of holistic treatments, Serenity Recovery Center of Marne, Michigan, has ... , Sickle Cell Disease (SCD) is a disorder of the red blood cells, which ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... 23, 2016 Bracket , a leading clinical ... generation clinical outcomes platform, Bracket eCOA (SM) 6.0, at ... 26 – 30, 2016 in Philadelphia , ... Outcome Assessment product of its kind to fully integrate with ... Bracket eCOA 6.0 is a flexible platform for electronic clinical ...
(Date:6/23/2016)... BOGOTA, Colombia , June 23, 2016  Astellas today announced the establishment of Astellas Farma Colombia (AFC), a ... second affiliate in Latin America . ... ... ... ...
(Date:6/23/2016)... 23, 2016 The vast majority of dialysis ... facility.  Treatments are usually 3 times a week, with ... including travel time, equipment preparation and wait time.  This ... grueling for patients who are elderly and frail.  Many ... and rehabilitation centers for some duration of time. ...
Breaking Medicine Technology: