Hot damn! This is a question I've been wondering about for some time.

Scientists Uncover How Brain Perceives Color

Scientists have discovered how the brain perceives color in a finding that could one day help people who have lost their sight.

By studying macaque monkeys, researchers at the University of Texas-Houston Medical School have shown how modules of cells called "thin stripes" in a particular region of the brain are arranged and perceive colors.

"This finding provides the first physiological basis for the perception of the full gamut of color," said Daniel Felleman, a professor of neurobiology and anatomy.

Felleman and his team mapped changes in blood flow along the stripes in the brains of the monkeys while showing them a series of colors. Their findings are reported in the science journal Nature.

While the monkeys looked at different colors, the blood flow peaks in their brains shifted systematically in specific portions of the stripes. An area with a peak flow for red was next to the portion that peaked for orange, then yellow, etc.

"We believe that the brain uses a spatial code for color such that the location of the peak activity within these color maps determines the color that you see," Felleman added in a statement.

Snagged from debate

This is apparently off the AP Wire.

NEW YORK (AP) - The White House said Wednesday it postponed a poetry symposium because of concerns that the event would be politicized. Some poets had said they wanted to protest military action against Iraq.

The symposium on the poetry of Emily Dickinson, Langston Hughes and Walt Whitman was scheduled for Feb. 12. No future date has been announced.

"While Mrs. Bush respects the right of all Americans to express their opinions, she, too, has opinions and believes it would be inappropriate to turn a literary event into a political forum." Noelia Rodriguez, spokeswoman for first lady Laura Bush, said Wednesday.

Mrs. Bush, a former librarian who has made teaching and early childhood development her signature issues, has held a series of White House symposiums to salute America's authors. The gatherings are usually lively affairs with discussions of literature and its societal impact.

But the poetry symposium soon inspired a nationwide protest.

Sam Hamill, a poet and founder of the highly regarded Copper Canyon Press, declined the invitation and e-mailed friends asking for anti-war poems or statements. He encouraged those who planned to attend to bring along anti-war poems.

Hamill said he's gotten more than 1,500 contributions, including ones from poets W.S. Merwin, Adrienne Rich and Lawrence Ferlinghetti.

"I'm putting in 18-hour days. I'm 60 and I'm tired, but it's pretty wonderful," says Hamill, based in Port Townsend, Wash., and author of such works as "Destination Zero" and "Gratitude."

Marilyn Nelson, Connecticut's poet laureate, said Wednesday that she had accepted the White House invitation and had planned to wear a silk scarf with peace signs that she commissioned.

"I had decided to go because I felt my presence would promote peace," she said.

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Meth Mouth

Another Danger of Drug Abuse: Cavities, Gum Disease

As the number of regular users of the illegal drug methamphetamine has increased, so has a peculiar set of dental problems linked to the drug--aptly named "meth mouth," according to US dentists.

The exact rate of meth mouth is unknown, but dentists who practice in areas where people have regular access to methamphetamine--also known as "crystal meth" and "crank," among other terms--are beginning to see a pattern.

"I have a certain number of patients who are starting to show up with it," said Dr. Eric Curtis, a dentist in private practice in Safford, Arizona, and a spokesman for the Academy of General Dentistry.

And the patients it crops up in most commonly are teenagers, he noted.
Approximately one year ago, Curtis said he began to notice patients with symptoms of meth mouth--specifically, a great deal of tooth decay, gum disease and cracks in the teeth.

He said he first became aware of the existence of meth mouth when a friend called and said her son was found in possession of methamphetamine, and she wanted Curtis to check his teeth.

"It was a surprise to me that a person I knew, a long-time patient, a long-time friend, called me and said 'I need you to screen my son for meth mouth.' And I said, 'what's that?"' Curtis recounted.

In an interview, Curtis explained that meth use could produce the symptoms ascribed to meth mouth because the drug dries out the salivary glands. Saliva acts as a buffer against acidic substances in the mouth, he explained, normally protecting teeth against acidic foods like lemons, acid from the gut or acidic plaque.

Without saliva, these substances can wreck havoc on teeth and gums, Curtis said.

[...] Most medications also dry out the mouth, he said, but methamphetamine "is especially bad this way."

Regular meth users may develop cracks in teeth because the drug can also make people feel anxious or nervous, causing them to clench or grind their teeth, Curtis added.

The dentist said he assembled the symptoms of meth mouth through his own experience with the handful of patients he sees with the condition, and by discussing it with his colleagues.

He added that he does not treat the tooth decay and gum disease associated with meth mouth any differently than he treats the conditions in other patients.

Ah. The right motivation for exercise.

Keeping Your Mind Fit

If you want to keep your brain healthy as you age, make sure you get plenty of exercise.

A new study, from the University of Illinois at Urbana-Champaign, says three areas of the brain that are adversely affected by aging stay in better shape when a person keeps their body physically fit. The study appears in the February issue of the Journal of Gerontology.

This is the first study to show anatomical differences in white and gray brain matter between older people who are physically fit and those who are less fit.

The study included 55 people over the age of 55. The researchers used high-resolution magnetic resonance imaging to assess the brains of the study participants.

The researchers focused on three areas -- the frontal, temporal and parietal cortexes. The study found distinct differences between the physically fit people and the less fit people. Those differences were especially apparent in two types of brain tissue -- white and gray matter.

The gray matter in your brain consists of thin layers of cell bodies such as neurons. Gray matter also includes support cells that are important in learning and memory. White brain matter is the myelin sheath that contains nerve fibers that transmit signals throughout the brain.

As you age, these white and gray matter tissues shrink in a pattern that closely matches declines in cognitive performance.