Color Vision

A Cure for Color Blindness May Be Found

Researchers at the University of Washington report in the journal Nature that they have been able to restore full color vision to adult monkeys born without the ability to distinguish between the colors red and green.

According to National Public Radio, scientists who study color vision are calling the study dazzling.

Until now scientists thought that this sort of therapy was not possible. However, the University of Washington team were able to introduce therapeutic genes into the light-sensing cells at the back of the eye of adult male squirrel monkeys, who are born red-green colorblind.

Furthermore, the monkeys were treated over two years ago and their improvement in color vision has remained stable since.

Link: 'Gene cure' for colour blindness [BBC]

Is There a Railroad Surgeon in the House?

I have just stumbled across an obscure and wonderful book, thanks the to efforts of Google to digitize the world's printed material. It's the 1895 edition of Color-vision and Color-blindness: A Practical Manual for Railroad Surgeons by J. Ellis Jennings, MD.  The title alone evokes all kinds of thoughts. Who knew there were such things as railroad surgeons?  They must have been the precursor to flight surgeons.  And who knew that color-blindness was such a problem in the railroads that not just a manual was required on the market, but a practical manual (no esoteric manual for me, thank you very much).

Well, it seems that in the 1890s color-blindness was a big deal. Dr. Jennings informs us that

"In 1875 a serious railway accident occurred in Sweden, which intensely excited public attention. At the investigation which followed it was found that colorblindness was one of the principal causes of the disaster."

Horrors!

You'll enjoy Jenning's history of color-blindness, the evolution of detecting color-blindness among railroaders, and the descriptions of the color blind tests used at the time.  My favorite?  Here's a picture of Thomson's Stick. 

Yep, that's the official name of the test. It's a "stick."

Link: Color-vision and Color-blindness: A Practical Manual for Railroad Surgeons

 

Using Color Without Seeing Color

Just because you're colorblind doesn't mean you can't do beautiful things with color.  I've pointed out colorblind artists before, but perhaps it's the cuttlefish that takes the prize for utilizing color while not being able to see any at all.  Okay, cuttlefish aren't human, they're cephalopods (examples of cephalopods are squids, octopus), but once you see their talents you'll certainly agree they are artists.

Take a look at the cuttlefish's amazing ability in this clip. Remember, cuttlefish can see no color.

How can they do this? Dr. Zen Faulkes, in reviewing a new research paper on the topic by Mäthger, Chiao, Barbosa, and Hanlon, says

This new paper tests the idea that the colours that cuttlefish can make are similar enough to the colours found in their natural habitat that the animals don't need to see colour. That is, if you can change colour to many different shades of brown, you are not likely to stand out too much if you inhabit an area where most things are brown. (emphasis in the original)

Not that I intend to discount the many moods of Tombi, but in my book the cuttlefish has the use-of-color talent nailed over the rest of the animal kingdom.

Link: Using Color Without Seeing Color posted at Neuro Dojo

Apparently Everyone's Colorblind

This week we see the following colorblind items coming through the tubes:

Colorblind Simualtion

Link: How to simulate colorblindness at ColorJack (via Using canvas to test your site with colorblind folk).

Software for People Who Are Colorblind

A student founded a company that produces a computer program enabling colorblind people to see color they would otherwise miss

Link: BIZOnline - Pair giving colour-blind a new vision.

Are We Ready To See Colors That Have Never Been Seen Before?

It turns out, thanks the power of genetic manipulation, that everyone may be colorblind since there are some colors that no one has ever seen. Yet.

Link: Seeing Colors That Have Never Been Seen

Giving New Meaning to the Term "Blind Review"

Suppose you're a scientist.  Suppose you write papers and proposals that are reviewed by your peers.  Suppose your paper is reviewed by three white males (not impossible). What's the probability that one of the reviewers is colorblind? 

According to Masataka Okabe and Kei Ito, the answer is 22%. 

Seriously?

Seriously. Since one in twelve Caucasians (8%) is colorblind, it goes like this:
[ 22% = 1-(1-0.92)^3 ].

If that's not enough to scare you into making figures and presentations that are friendly to colorblind people, maybe this will:  In any room of 250 or more people there are probably at least ten people who are colorblind. These demographics are, in part, why Okabe and Ito have authored a sensible guide on how to select colors and graphics that are unambiguous to both colorblinds and non-colorblinds.

While their essay is aimed at improving the lot of work created by authors in the ivory tower, their points should be heeded by scribblers of all ilk.

Among their most important points:

• Advice to not use a combination of red and green. They suggest using magenta instead of red, which really works. In the two images above, the top image contains red that is very difficult to distinguish from the green when viewed by those with red-green colorblindness.  Conversely, when the authors present the same image with magenta substituted for red, distinguishing the two colors becomes no problem for those with red-green colorblindness.
• For graphs and line drawings, Okabe and Ito suggest labeling elements of the graph on the graph itself rather than making a separate color-coded key. For those who are colorblind, matching the same colors in different places on a chart is extremely difficult. I can confirm this from experience.
• Red is not necessarily a bright color and does not stand out well against black or green.

To their credit, Okabe and Ito have created a PowerPoint slide version of their article. It contains all the key points and tips.  Unfortunately, the slide show could benefit from a touch of design. Too bad they haven't met Garr Reynolds or Cliff Atkinson.

Link: Colorblind Barrier Free: How to make figures and presentations that are friendly to colorblind people.

Next Up: Web Browser For The Color Blind

Guest post by Zack Ybara

I stumbled upon an interesting post by Alexia Golez, a self-proclaimed “geek” from Ireland. Seems that a yearly Science & Technology exhibit called the BT Young Scientist Exhibit (YSE) 2008 is currently ongoing, and the young Irish scientists have some quite impressive projects and prototypes on show.

Two of these young scientists include Adam Kielthy and Conor Scully, both from Sutton Park School. Their project was a Web Browser for the Colour Blind, and it tackled changing the approach to interpreting web content. As noted in a previous post, over 101 million of the world’s netizens are color blind, and improving the accessibility for these individuals would be praiseworthy.

These days when brick-and-mortar establishments are no longer the only way to go, and when college degrees are no longer the only ticket to a good career, it’s heartening to see bright young individuals like Adam and Conor coming up with solutions that elude scientists many years their senior. We’ll be keeping our eyes on them in the years to come.

Martian colors, or seeing colors you're not supposed to see

Bear with me. You won't regret it. I want to talk about synesthesia for a sec.

Synesthesia is "a neurologically based phenomenon in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway." [Wikipedia]

For instance, there is a form of synesthesia called "grapheme" where letters or numbers are perceived as always being a certain color. The color associated with the letter or number varies from person to person experiencing the sensation. The image above is representative of how someone with synesthesia might perceive certain letters and numbers.

Here's the interesting part.

John Fossella blogged this week about an article by V. S. Ramachandrans and  Edward M. Hubbard in which the authors said

“We also observed one case in which we believe cross activation enables a colorblind synesthete to see numbers tinged with hues he otherwise cannot perceive; charmingly, he refers to these as “Martian colors.” Although his retinal color receptors cannot process certain wavelengths, we suggest that his brain color area is working just fine and being cross-activated when he sees numbers.”

In other words, this person could see colors he wasn't supposed to be able to see. He could "cross-activate" his brain and fire up the perception of a color his retinas weren't equipped to process.

Mighty amazing.

Link: More Common Questions about Synesthesia: Scientific American.