Mechanism of 'blindsight' explored

Oct 31, 2005

Rice University researchers report inducing temporary "blindsight" in healthy volunteers.

Blindsight is a phenomenon in which people with a deactivated primary visual cortex -- an area of their brain essential for visual perception -- can still sense objects in their field of vision.

Researcher Tony Ro and colleagues tested blindsight in human subjects with normal vision.

Using an electromagnetic brain stimulation technique, the researchers deactivated the primary visual cortex in 12 volunteers. An object on a screen -- such as a colored disk or a horizontal or vertical bar -- was then flashed in front of the temporarily blinded volunteers.

Although the volunteers reported no awareness of the objects' characteristics the majority of the time, they also guessed correctly at a level significantly higher than chance.

The results suggest the existence of a visual pathway that bypasses the primary visual cortex and can process some characteristics unconsciously, the scientists said.

The research appears in the online early edition of the Proceedings of the National Academy of Sciences.

Copyright 2005 by United Press International

Explore further: Changing dinosaur tracks spurs novel approach

add to favorites email to friend print save as pdf

Related Stories

NeuroImage: Multiplexing in the visual brain

Mar 24, 2011

Imagine sitting in a train at the railway station looking outside: Without analyzing the relative motion of object contours across many different locations at the same time, it is often difficult to decide ...

Researchers identify new neurological deficit behind lazy eye

Sep 10, 2010

Researchers at New York University's Center for Neural Science have identified a new neurological deficit behind amblyopia, or "lazy eye." Their findings, which appear in the most recent issue of the Journal of Neuroscience, shed a ...

Scientists find explanation for blindsight

Jun 25, 2010

(PhysOrg.com) -- The rare phenomenon of blindsight has been known for a long time, but until now has never been understood. People with blindsight are effectively blind through damage to the primary visual ...

Experience shapes the brain's circuitry throughout adulthood

Jun 15, 2010

The adult brain, long considered to be fixed in its wiring, is in fact remarkably dynamic. Neuroscientists once thought that the brain's wiring was fixed early in life, during a critical period beyond which changes were impossible. ...

Recommended for you

Newlyweds, be careful what you wish for

15 hours ago

A statistical analysis of the gift "fulfillments" at several hundred online wedding gift registries suggests that wedding guests are caught between a rock and a hard place when it comes to buying an appropriate gift for the ...

Can new understanding avert tragedy?

18 hours ago

As a boy growing up in Syracuse, NY, Sol Hsiang ran an experiment for a school project testing whether plants grow better sprinkled with water vs orange juice. Today, 20 years later, he applies complex statistical ...

Crowd-sourcing Britain's Bronze Age

18 hours ago

A new joint project by the British Museum and the UCL Institute of Archaeology is seeking online contributions from members of the public to enhance a major British Bronze Age archive and artefact collection.

Roman dig 'transforms understanding' of ancient port

19 hours ago

(Phys.org) —Researchers from the universities of Cambridge and Southampton have discovered a new section of the boundary wall of the ancient Roman port of Ostia, proving the city was much larger than previously ...

User comments : 0

More news stories

Newlyweds, be careful what you wish for

A statistical analysis of the gift "fulfillments" at several hundred online wedding gift registries suggests that wedding guests are caught between a rock and a hard place when it comes to buying an appropriate gift for the ...

Can new understanding avert tragedy?

As a boy growing up in Syracuse, NY, Sol Hsiang ran an experiment for a school project testing whether plants grow better sprinkled with water vs orange juice. Today, 20 years later, he applies complex statistical ...

Roman dig 'transforms understanding' of ancient port

(Phys.org) —Researchers from the universities of Cambridge and Southampton have discovered a new section of the boundary wall of the ancient Roman port of Ostia, proving the city was much larger than previously ...

Crowd-sourcing Britain's Bronze Age

A new joint project by the British Museum and the UCL Institute of Archaeology is seeking online contributions from members of the public to enhance a major British Bronze Age archive and artefact collection.

Better thermal-imaging lens from waste sulfur

Sulfur left over from refining fossil fuels can be transformed into cheap, lightweight, plastic lenses for infrared devices, including night-vision goggles, a University of Arizona-led international team ...

Hackathon team's GoogolPlex gives Siri extra powers

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...

Chronic inflammation linked to 'high-grade' prostate cancer

Men who show signs of chronic inflammation in non-cancerous prostate tissue may have nearly twice the risk of actually having prostate cancer than those with no inflammation, according to results of a new study led by researchers ...