Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Moving the mind’s eye depends upon an intact eye movement system

04.05.2004


An important aspect of human vision is the ability to attend to objects or events appearing in our peripheral vision without shifting our gaze. This way of effectively looking out of the corner of the mind’s eye is thought to be particularly important for alerting us to danger. Researchers have made the seemingly paradoxical discovery that even though eye movement itself is actually dispensable for such an attention shift, eye muscle function is nevertheless required for this ability to reflexively redirect one’s attention. The new finding tests an important theory about brain function, and represents a remarkable example of the brain’s complex relationship with movement.



The ability to attend to objects or events that are not at the current centre of gaze (e.g., rapid movements which might signal danger) is referred to as the covert orienting of attention. This mechanism can be contrasted with the overt orienting of attention which typically involves the execution of an eye movement (saccade) intended to bring the object of interest into central vision.

In their new work, researchers Daniel Smith, Chris Rorden and Stephen Jackson of the University of Nottingham, UK, address an important question concerning the precise relationship between eye movements and the covert orienting of attention. While some have argued that covert orienting of attention and eye movements are independent of one another, other researchers have supported the so-called "premotor theory" of attention, which holds that covert attention is mediated by the same system that controls saccadic eye movements, and that a covert shift of attention is simply an unexecuted eye movement.


In a novel test of the premotor hypothesis, Smith and colleagues investigated the covert orienting of attention by a woman (AI) who, because of a congenital impairment in the development of her eye muscles (opthalmoplegia), had never been able to make an eye movement, but could read and scan the visual world by making saccadic head movements.

The researchers found that in contrast to individuals who possessed the ability to move their eyes, AI could not reflexively orient her attention in response to the appearance of a salient peripheral cue. Nevertheless she had no problem orienting her attention voluntarily in response to centrally presented direction cues (i.e., an arrow pointing left or right).

The results demonstrate that intact eye movements are necessary for the normal development of reflexive attention. They also show that, contrary to what one might expect, intact brain regions alone are not sufficient for the normal development of attention. Together the new findings provide strong support for the premotor theory of attention.


Daniel T. Smith, Chris Rorden, and Stephen R. Jackson : "Exogenous Orienting of Attention Depends upon the Ability to Execute Eye Movements"

Publishing in Current Biology, Volume 14, Number 9, May 4, 2004.

Heidi Hardman | EurekAlert!

More articles from Life Sciences:

nachricht New mechanisms regulating neural stem cells
21.02.2019 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht A landscape of mammalian development
21.02.2019 | Max-Planck-Institut für molekulare Genetik

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Light from a roll – hybrid OLED creates innovative and functional luminous surfaces

Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.

The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...

Im Focus: Regensburg physicists watch electron transfer in a single molecule

For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.

The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...

Im Focus: University of Konstanz gains new insights into the recent development of the human immune system

Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens

Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...

Im Focus: Transformation through Light

Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light

When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...

Im Focus: Famous “sandpile model” shown to move like a traveling sand dune

Researchers at IST Austria find new property of important physical model. Results published in PNAS

The so-called Abelian sandpile model has been studied by scientists for more than 30 years to better understand a physical phenomenon called self-organized...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Global Legal Hackathon at HAW Hamburg

11.02.2019 | Event News

The world of quantum chemistry meets in Heidelberg

30.01.2019 | Event News

Our digital society in 2040

16.01.2019 | Event News

 
Latest News

A Volcanic Binge And Its Frosty Hangover

21.02.2019 | Earth Sciences

Cleaning 4.0 in the meat processing industry – higher cleaning efficiency

21.02.2019 | Trade Fair News

New mechanisms regulating neural stem cells

21.02.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>