Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Evidence for expanded color vision for some colorblind individuals

06.12.2005


Some forms of colorblindness may actually afford enhanced perception of some colors, according to findings reported this week in Current Biology by John Mollon and colleagues at the University of Cambridge.



The most common form of colorblindness is an X-chromosome-linked variant form of color vision technically known as deuteranomaly. Colors are detected by humans through the combined action of three different types of so-called cone photoreceptors, each of which is optimally activated by different wavelengths of light. These sensitivities are altered in deuteranomalous colorblind individuals because they possess a variant form of one of the cone photoreceptors--the sensitivity of cones that should be "middle-wave" is shifted toward that of "long-wave" cones, resulting in decreased ability to differentiate between some colors that are easily distinguishable by those with normal color vision. In theory, however, it is possible that owing to the altered sensitivities of their cone photoreceptors, deuteranomalous individuals may be sensitive to color differences that are not apparent to those with normal color vision.

In the new work, researchers tested this idea by asking deuteranomalous and "color-normal" individuals to report whether they were able to distinguish between pairs of colors that were theoretically predicted to look different to deuteranomalous colorblind individuals but to appear the same to those with normal color vision. Indeed, the researchers found that some color pairs were only seen to be different by deuteranomalous individuals. The finding suggests that although these individuals may be blind to some colors accessible by color-normal individuals, they also have a sensitivity to a "color dimension" that is inaccessible to those with normal color vision. In their paper, the researchers remark that "[f]or a color-normal experimenter, it was striking to watch a deuteranamolous subject giving large difference ratings to apparently identical stimuli, and doing so without hesitation."


The researchers point out that because deuteranamolous colorblindness is caused by an X-chromosome-linked genetic alteration, and because women randomly inactivate one of their two X chromosomes in each of their cells, women who are carriers of the deuteranamoly trait (and hence have one normal X chromosome) are predicted to express four types of cone photoreceptor--the three normal cone types, as well as the cone with a shifted wavelength sensitivity. Thought it is unclear whether this would appreciably affect color vision in a way that allows expanded color sensitivities without the colorblindness experienced by deuteranamolous individuals, a test similar to that utilized in the present study could potentially be used to test this possibility.

Heidi Hardman | EurekAlert!
Further information:
http://www.current-biology.com

More articles from Life Sciences:

nachricht Copper hydroxide nanoparticles provide protection against toxic oxygen radicals in cigarette smoke
29.05.2017 | Johannes Gutenberg-Universität Mainz

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Camera on NASA's Lunar Orbiter survived 2014 meteoroid hit

29.05.2017 | Physics and Astronomy

Strathclyde-led research develops world's highest gain high-power laser amplifier

29.05.2017 | Physics and Astronomy

A 3-D look at the 2015 El Niño

29.05.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>