Scientists at Durham University have confirmed that colour contrast is first detected by part of the brain called primary visual cortex, which is located at the very back of the head where visual information first enters the cortex of the brain. This was recently discovered to be the case in animals but has not been tested on human beings until now.
The research also confirms that the brain does most of the work in seeing the difference between colours, rather than the eye.
The team of neuropsychologists identified a patient with damage to this specific part of the brain. They showed the patient visual illusions in which the contrast between the coloured spots in the foreground and their background colour affected the way the spots looked. People with this part of the brain intact would see the spots as different as they look different on varying backgrounds. The patient was not able to detect that difference.
The research, which is published in the Proceedings of the National Academy of Sciences this week, makes a significant contribution to the understanding of how the brain functions.
Dr Robert Kentridge, lead researcher and lecturer in Durham University’s Psychology Department explains: “Colour is a product of our nervous system – it is a ‘pigment’ of our imagination. The colours that we see are more related to the materials that things are made of than the light reflected from them into our eyes. Making this happen involves many complex processes. One of the earliest involves seeing contrast between pairs of colours. We have found that this important step of seeing colour contrast happens much earlier in the brain than we had realised up to now.”
The research study used a common approach in neuropsychology, that of extensive testing of a single patient, in this case one who had portions of the right primary visual cortex surgically removed in 1973 for treatment of abnormal blood vessels in the brain.
Professor Charles Heywood, who leads Durham’s Psychology Department, added: “People can distinguish between colours partly because of the contrast with its background. If someone has lost that ability through brain damage, it means that they might see colours as changing all the time. The colour of clothes, and indeed everything else we see, would change dramatically, depending on the colour of light which shines on them.”
The study was supported by a grant from the Medical Research Council.
Media and Public Affairs Team | alfa
Researchers simplify tiny structures' construction drip by drip
12.11.2018 | Princeton University, Engineering School
Mandibular movement monitoring may help improve oral sleep apnea devices
06.11.2018 | Elsevier
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
19.11.2018 | Event News
09.11.2018 | Event News
06.11.2018 | Event News
19.11.2018 | Materials Sciences
19.11.2018 | Information Technology
19.11.2018 | Life Sciences