Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


The dual functions of sight – perception and action – demonstrated for first time


The dissociation in the visual system between two separate functions – one that enables us to identify objects and the other to interact with them – has been clearly demonstrated for the first time in healthy humans by researchers at the Hebrew University of Jerusalem.

These separate vision-related actions have been documented from the beginning of the 20th century in patients who suffered damage to the visual system as a result of illness or injuries in which one or the other function – identification or action – was damaged.

For example, persons suffering from ataxia are able to verbally identify an object presented to them but have difficulty in grasping it, while those who have agnosia can grasp an object if handed to them but are unable to name or indicate the position, size or texture of the object.

This dissociation between action and perception suggests the existence of two separate visual streams However, despite the wide research triggered by this theoretical concept, it had not been proved in subjects in whom both streams are functioning normally.

Now, through the use of functional magnetic resonance imaging (fMRI), Prof. Ehud Zohary and his graduate student Lior Shmuelof of the Department of Neurobiology at the Alexander Silberman Institute of Life Sciences at the Hebrew University have been able to demonstrate dissociation between perception of objects and actions in the brains of healthy persons. An article detailing their findings was published as the cover story in the journal Neuron.

In the article, the researchers described how they were able to observe dissociation between dorsal and ventral activation patterns in the brains of participants who were shown video scenes of objects and actions directed towards those objects.

What Shmuelof and Zohary saw in the fMRI images were that a complex in the occipito-temporal cortex area of the brain responded to the identity of an object presented on the screen, while a different complex in the parietal lobe region reacted when the subjects were shown actions directed at those objects.

The researchers point out that the areas of the brain responsible for motor action were activated when the experimental subjects were shown scenes of action, even though the subjects were in a passive state, viewing only video clips presenting actions by others, and were not involved in any way with the activities being screened.

What this suggests is that there is an interrelationship between guiding of our own actions and understanding actions taken by others – a kind of "stepping into another’s shoes" that may be one of the bases underlying social communication.

Jerry Barach | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Scientists develop tiny tooth-mounted sensors that can track what you eat
22.03.2018 | Tufts University

nachricht NIH scientists describe potential antibody treatment for multidrug-resistant K. pneumoniae
14.03.2018 | NIH/National Institute of Allergy and Infectious Diseases

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

Modular safety concept increases flexibility in plant conversion

22.03.2018 | Trade Fair News

New interactive map shows climate change everywhere in world

22.03.2018 | Earth Sciences

New technologies and computing power to help strengthen population data

22.03.2018 | Earth Sciences

Science & Research
Overview of more VideoLinks >>>