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Learning to Read as an Adult Changes Deep Regions of the Brain

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In the evolutionary history of humans, reading and writing are relatively new functions. As a result, in order to read written language, human brains have had to recruit and adapt parts of the visual system to interface with language centers. This is a process researchers have long believed occurred primarily in the cerebral cortex, the outer layer of the brain. But in a new study where illiterate people in their thirties were trained to read over six months, researchers have discovered that reading actually activates much deeper brain structures as well, opening doors to a better understanding of how we learn, and possible new interventions for dyslexia. Their results were recently published in the journal Science Advances.

In order to learn to read, "a kind of recycling process has to take place in the brain," Falk Huettig, one of the collaborating researchers at Max Planck Institute for Human Cognitive and Brain Sciences, tells Mental Floss by email. "Areas evolved for the recognition of complex objects, such as faces, become engaged in translating letters into language.”

To study this process in the brain, researchers selected participants from India, where the literacy rate is about 63 percent, a rate influenced by poverty, which limits educational access, especially for girls and women. Most of the participants in this study were women in their thirties who came into the study unable to read a single word.

They divided the participants into a group that received reading training intervention and a control group that was not trained. Both groups underwent functional magnetic resonance imaging (fMRI) brain scans before and after the six-month study. Some participants were excluded due to incomplete scanning sessions, leaving a total of 30 participants in the final analysis.

They were taught to read Devanagari, the script upon which Hindi and some other languages of South Asia are based. It's an alpha-syllabic script composed of complex characters that describe whole syllables or words.

The instructor was a professional teacher who followed the locally established method of reading instruction. During the first month of instruction, the participants first were taught to read and write 46 primary Devanagari characters simultaneously. After learning the letters and reading single words, they were taught two-syllable words. In all, they studied approximately 200 words in the first month.

In the second month, the participants were then taught to read and write simple sentences, and in the third month, they learned more complex, three-syllable words. Finally, in the second half of the program, participants learned some basic grammar rules. "For example, the participants learned about the differences between nouns, pronouns, verbs, proverbs, and adjectives, and also about basic rules of tense and gender," Huettig says.

Within six months, participants who could read between zero and eight words even before the training had reached a first-grade level of reading, according to Huettig. "This process was quite remarkable," Huettig says. "Learning to read is quite a complex skill, as arbitrary script characters must be mapped onto the corresponding units of spoken language."

When the researchers looked at the brain scans taken before and after the six-month training, Huettig says they expected to simply replicate previous findings: that changes are limited to the cortex, which is known to adapt quickly to new challenges.

What they didn't expect was to see changes in deeper parts of the brain. "We observed that the learning process leads to a reorganization that extends to deep brain structures in the thalamus and the brainstem." More specifically, learning to read had an impact on a part of the brainstem called the superior colliculus as well as the pulivinar, located in the thalamus, which "adapt the timing of their activity patterns to those of the visual cortex," Heuttig explains.

These deep brain structures help the visual cortex filter important information from the flood of visual input—even before we consciously perceive it. "It seems that these brain systems increasingly fine-tune their communication as learners become more and more proficient in reading," he says.

In essence, the more these participants read, the better they became at it. The research also revealed that the adult brain is more adaptable than previously understood. "Even learning to read in your thirties profoundly transforms brain networks," Huettig says. "The adult brain is remarkably flexible to adapt to new challenges."

Even more promising, these results shed new light on a possible cause of dyslexia, a language-processing disorder, which researchers have long attributed to dysfunctions of the thalamus. Since just a few months of reading training can modify the thalamus, Huettig says, "it could also be that affected people show different brain activity in the thalamus, just because their visual system is less well-trained than that of experienced readers."

Huettig feels that the social implications of this kind of research are huge, both for people effected by dyslexia as well as the hundreds of millions of adults who are completely or functionally illiterate around the world. Huettig says the new findings could help "put together literacy programs that have the best chance of succeeding to help these people."

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Women Suffer Worse Migraines Than Men. Now Scientists Think They Know Why
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Migraines are one of medicine's most frustrating mysteries, both causes and treatments. Now researchers believe they've solved one part of the puzzle: a protein affected by fluctuating estrogen levels may explain why more women suffer from migraines than men.

Migraines are the third most common illness in the world, affecting more than 1 in 10 people. Some 75 percent of sufferers are women, who also experience them more frequently and more intensely, and don't respond as well to drug treatments as men do.

At this year's Experimental Biology meeting in San Diego, researcher Emily Galloway presented new findings on the connection between the protein NHE1 and the development of migraine headaches. NHE1 regulates the transfer of protons and sodium ions across cell membranes, including the membranes that separate incoming blood flow from the brain.

When NHE1 levels are low or the molecule isn't working as it's supposed to, migraine-level head pain can ensue. And because irregular NHE1 disrupts the flow of protons and sodium ions to the brain, medications like pain killers have trouble crossing the blood-brain barrier as well. This may explain why the condition is so hard to treat.

When the researchers analyzed NHE1 levels in the brains of male and female lab rats, the researchers found them to be four times higher in the males than in the females. Additionally, when estrogen levels were highest in the female specimens, NHE1 levels in the blood vessels of their brains were at their lowest.

Previous research had implicated fluctuating estrogen levels in migraines, but the mechanism behind it has remained elusive. The new finding could change the way migraines are studied and treated in the future, which is especially important considering that most migraine studies have focused on male animal subjects.

"Conducting research on the molecular mechanisms behind migraine is the first step in creating more targeted drugs to treat this condition, for men and women," Galloway said in a press statement. "Knowledge gained from this work could lead to relief for millions of those who suffer from migraines and identify individuals who may have better responses to specific therapies."

The new research is part of a broader effort to build a molecular map of the relationship between sex hormones and NHE1 expression. The next step is testing drugs that regulate these hormones to see how they affect NHE1 levels in the brain.

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A Founder of Earth Day Looks Back on How It Began
Vivien Killilea/Getty Images for Caruso Affiliated
Vivien Killilea/Getty Images for Caruso Affiliated

On the very first Earth Day in 1970, Denis Hayes stood on a stage in Central Park, stunned by the number of people who'd come to honor the planet. Now in his 70s, Hayes remembers it was like looking at the ocean—“you couldn’t see where the sea of people ended.” Crowd estimates reached more than a million people.

For Hayes, who is now board chair of the international Earth Day Network, it was the culmination of a year’s worth of work. As an urban ecology graduate student at Harvard University, he’d volunteered to help organize a small initiative by Wisconsin senator Gaylord Nelson. Nelson was horrified by the 1969 oil spill in Santa Barbara, California, and wanted to raise awareness about environmental issues by holding teaching events similar to those being held by civil rights and anti-war activists.

Senator Nelson saw a growing disconnect between the concept of progress and the idea of American well-being, Hayes tells Mental Floss. “There was a sense that America was prosperous and getting better, but at the same time, the air in the country was similar to the air today in China, Mexico City, or New Delhi," Hayes says. "Rivers were catching on fire. Lakes were unswimmable.”

Nelson's plan for these environmental teach-ins was for speakers to educate college students about environmental issues. But he had no one to organize them. So Hayes, Nelson’s sole volunteer, took control on a national level, organizing teach-ins at Harvard first and then across the U.S. Initially, the response was tepid at best. “Rather rapidly it became clear that this wasn’t a hot issue at colleges and universities in 1969,” Hayes says. “We had a war raging, and civil rights were getting very emotional after the Nixon election.”

Still, both Hayes and Nelson noticed an influx of mail to the senator's office from women with young families worried about the environment. So instead of focusing on colleges, the two decided to take a different tactic, creating events with community-based organizations across the country, Hayes says. They also decided that rather than a series of teach-ins, they'd hold a single, nationwide teach-in on the same day. They called it Earth Day, and set a date: April 22.

Hayes now had a team of young adults working for the cause, and he himself had dropped out of school to tackle it full time. Long before social media, the project began to spread virally. “It just resonated,” he says. Women and smaller environmental-advocacy groups really hooked onto the idea, and word spread by mouth and by information passing between members of the groups.

Courtesy of Denis Hayes

With the cooperation and participation of grassroots groups and volunteers across the country, and a few lawmakers who supported the initiative, Hayes’ efforts culminated in the event on April 22, 1970.

Hayes started the day in Washington, D.C., where he and the staff were based. There was a rally and protest on the National Mall, though by that point Hayes had flown to New York, where Mayor John Lindsay provided a stage in Central Park. Parts of Fifth Avenue were shut down for the events, which included Earth-oriented celebrations, protests, and speeches by celebrities. Some of those attending the event even attacked nearby cars for causing pollution. After the rally, Hayes flew to Chicago for a smaller event.

“We had a sense that it was going to be big, but when the day actually dawned, the crowds were so much bigger than anyone had experienced before,” Hayes said. The event drew grassroots activists working on a variety of issues—Agent Orange, lead paint in poor urban neighborhoods, saving the whales—and fostered a sense of unity among them.

“There were people worrying about these [environmental] issues before Earth Day, but they didn’t think they had anything in common with one another," Hayes says. "We took all those individual strands and wove them together into the fabric of modern environmentalism.”

Hayes and his team spent the summer getting tear-gassed at protests against the American invasion of Cambodia, which President Nixon authorized just six days after Earth Day. But by fall, the team refocused on environmental issues—and elections. They targeted a “dirty dozen” members of Congress up for re-election who had terrible environmental records, and campaigned for candidates who championed environmental causes to run against them. They defeated seven out of 12.

“It was a very poorly funded but high-energy campaign,” Hayes says. “That sent the message to Congress that it wasn’t just a bunch of people out frolicking in the sunshine planting daisies and picking up litter. This actually had political chops.”

The early '70s became a golden age for environmental issues; momentum from the Earth Day movement spawned the creation of the Clean Air Act, the Clean Water Act, the Safe Drinking Water Act, the Endangered Species Act, the Marine Mammal Protection Act, the Environmental Education Act (which was initially passed in 1970 and revived in 1990), and the Environmental Protection Agency.

“We completely changed the framework within which America does business, more than any other period in history with the possible exception of the New Deal,” Hayes says. “But our little revolution was brought entirely from the grassroots up.”

In 1990, Hayes was at it again. He organized the first international Earth Day, with about 200 million participants across more than 140 countries. Since then it’s become a global phenomenon.

Despite its popularity, though, we still have a long way to go, even if the improvements Hayes fought for have made these issues feel more remote. Hayes noted that everything they were fighting in the '70s was something tangible—something you could see, taste, smell, or touch. Climate change can seem much less real—and harder to combat—to the average person who isn’t yet faced with its effects.

Hayes also notes that people have become more skeptical of science. “Historically, that has not been a problem in the United States. But today science is under attack.”

He warns, “This [anti-science sentiment] is something that could impoverish the next 50 generations and create really long-term devastation—that harms not only American health, but also American business, American labor, and American prospects.”

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