Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

More than meets the eye

10.10.2006
Ever watch a jittery video made with a hand-held camera that made you almost ill? With our eyes constantly darting back and forth and our body hardly ever holding still, that is exactly what our brain is faced with. Yet despite the shaky video stream, we usually perceive our environment as perfectly stable.

Not only does the brain find a way to compensate for our constantly flickering gaze, but researchers at the Salk Institute for Biological Studies have found that it actually turns the tables and relies on eye movements to recognize partially hidden or moving objects. Their findings will be published in a forthcoming issue of Nature Neuroscience.

"You might expect that if you move your eyes, your perception of objects might get degraded," explains senior author Richard Krauzlis, Ph.D., an associate professor in the Systems Neurobiology Laboratory at the Salk Institute. "The striking thing is that moving your eyes can actually help resolve ambiguous visual inputs."

Our eyes move all the time, whether to follow a moving object or to scan our surroundings. On average, our eyes move several times a second – in fact, in a lifetime, our eyes move more often than our heart beats. "Nevertheless, you don't have the sense that the world has just swept across or rotated around you. You sense that the world is stable," says Krauzlis.

... more about:
»Hafed »Krauzlis »Video »Visual »eye movement »movements

Just like high-end video cameras, the brain relies on an internal image stabilization system to prevent our perception of the world from turning into a blurry mess. Explains lead author Ziad Hafed, Ph.D. "Obviously, the brain has found a solution. In addition to the jumpy video stream, the visual system constantly receives feedback about the eye movements that the brain is generating."

Hafed and Krauzlis took the question of how the brain is able to maintain perception under less than optimal circumstances one step further. "If you think of the video stream as a bunch of pixels coming in from the eyes, the real challenge for the visual system is to decide which pixels belong to which objects. We wondered whether information about eye movements is used by the brain to solve this difficult problem," says Hafed, who is an NSERC (Canada) and Sloan-Swartz post-doctoral researcher at the Salk Institute.

Krauzlis explains that the human brain recognizes objects in everyday circumstances because it is very good at filling in missing visual information. "When we see a deer partially hidden by tree trunks in a forest, we can still segment the visual scene and properly interpret the individual features and group them together into objects," he says.

However, even though recognizing that deer is effortless for us, it is not a trivial accomplishment for the brain. Teaching computers to recognize objects in real life situations has proven to be an almost insurmountable problem. Artificial intelligence researchers have spent much time and effort trying to design robots that can recognize objects in unconstrained situations, but so far, their success has been limited.

To determine whether eye movements actually help the brain recognize objects, Hafed and Krauzlis asked whether people perceived an object better when they actively moved their eyes or when they stared at a given point in space. Human subjects watched a short video that allowed them to glimpse a partially hidden chevron shape that moved in a circle.

When they kept their eyes still by fixating on a stationary spot, observers perceived only random lines moving up and down. But when they moved their eyes such that the input video streams through them were unaltered, viewers easily recognized the lines as a circling chevron.

"It turns out that eye movements not only help with image stabilization, but that this additional input also plays a fairly important role for the perception of objects in the face of all the challenges that real life visual scenes pose – that objects are obscured or are moving, and so on," says Hafed.

Gina Kirchweger | EurekAlert!
Further information:
http://www.salk.edu

Further reports about: Hafed Krauzlis Video Visual eye movement movements

More articles from Life Sciences:

nachricht When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short
23.03.2017 | Institut für Pflanzenbiochemie

nachricht WPI team grows heart tissue on spinach leaves
23.03.2017 | Worcester Polytechnic Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short

23.03.2017 | Life Sciences

Researchers use light to remotely control curvature of plastics

23.03.2017 | Power and Electrical Engineering

Sea ice extent sinks to record lows at both poles

23.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>