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."

Archaeologists Uncover World's Oldest Known Brewery in Israel

People have been knocking back beers for 13,000 years, according to new archaeological findings out of the Middle East. As Science magazine reports, evidence of wheat and barley-based beer was found inside stone mortars carved into the floor of a cave near Haifa, Israel.

The Raqefet Cave was used as a burial site by the Natufians, a group of semi-nomadic hunter-gatherers who were also responsible for the world’s oldest known bread, which was discovered in Jordan in July. These findings challenge previous evidence that traced the origin of beer back just 5000 years.

Beer was also previously believed to be merely a by-product of bread-making, but archaeologists say that isn’t necessarily the case. Instead, researchers believe beer may been served during ritual feasts “to venerate the dead and/or to enhance group cohesion among the living,” researchers wrote in their paper, published in the Journal of Archaeological Science: Reports.

Remarkably, the Stanford University researchers who made this discovery weren't even looking for evidence of alcohol. “We did not set out to find alcohol in the stone mortars, but just wanted to investigate what plant foods people may have consumed because very little data was available in the archaeological record,” Li Liu, a professor of Chinese archaeology at Stanford, said in a statement.

Researchers theorize that beer brewing may have inspired the Natufians to cultivate cereals in the region, but it’s not currently known whether beer or bread came first. The mortars dug into the cave floor were reportedly used for storing and pounding wheat and barley, as well as brewing beer.

The beverage wasn’t exactly what we know as beer today, though. According to the BBC, the prehistoric beer was “gruel-like” and similar to porridge. It was likely weaker than modern beer, too.

[h/t Science]

Newly Uncovered Galileo Letter Details How He Tried to Avoid the Inquisition

Galileo Before The Papal Tribunal by Robert Henry. Hulton Archive, Getty Images
Galileo Before The Papal Tribunal by Robert Henry. Hulton Archive, Getty Images

Galileo Galilei was one of the Roman Catholic Inquisition’s most famous targets. As a result of his outspoken support for the theory that all the planets, Earth included, revolve around the Sun, the Catholic Church charged him with heresy and he spent the last years of his life under house arrest. Galileo was well aware that he was on the Church’s hit list, and a newly discovered letter shows that at one point, he tried to tone down his ideas to avoid persecution, according to Nature and Ars Technica.

The letter in question, written in 1613, solves a long-held mystery for Galileo scholars. It was found in the library of the Royal Society, where it has been for at least 250 years.

Galileo’s beef with the Catholic Church came about because of his support for heliocentrism—the idea that the solar system centers around the Sun—as advocated in Nicolaus Copernicus’s book De Revolutionibus. Galileo’s scientific writings clearly endorsed Copernicus’s theory of the world, including in personal correspondence that was widely disseminated, and in some cases, he directly questioned the scientific merit of Biblical passages.

In 1613, Galileo wrote to a friend and former student named Benedetto Castelli who was then teaching mathematics at the University of Pisa. The letter was a long treatise on Galileo’s thoughts on Copernicus’s ideas and religion, arguing that science and astronomy should not be overpowered by religious doctrin . (He would later expand this into his Letter to the Grand Duchess Christina.) As with many of Galileo’s writings at the time, the letter was copied and disseminated widely, and eventually, a friar named Niccolò Lorini forwarded it to the Inquisition in Rome in 1615.

This is where things get tricky. Galileo claimed that the version of the letter Lorini sent was doctored to be more inflammatory. He sent a less controversial version of the letter to a friend, saying that it was the original document and should be forwarded to the Vatican, essentially to clear his name. But scholars have never been able to be totally sure if he was telling the truth about the letter being doctored.

This newly discovered letter suggests that he was lying, and that he himself was looking to tone down his rhetoric to appease the Catholic Church and keep authorities from quashing the spread of heliocentric ideas. The original copy found in the Royal Society archives shows changes to the wording in what appears to be Galileo’s handwriting. The seven-page letter, signed “G.G.,” includes changes like swapping the word “false” for the more slippery “look different from the truth,” changing “concealing” to “veiling,” and other edits that seek to tone down the rhetoric that inflamed Church leaders. The wording and handwriting corresponds to similar writing by Galileo at the time. Based on this finding, it seems that Galileo did seek to make his ideas more palatable to the Catholic Church in the hopes of escaping persecution by the Inquisition.

Discovered on a research trip by science historian Salvatore Ricciardo of Italy's University of Bergamo, the letter may have been overlooked in the Royal Society archives because it was cataloged as being dated October 21, 1613 rather than the date it actually bears, December 21, 1613. However, it’s unclear how it came to the Royal Society in the first place. The document is the subject of a forthcoming article by Ricciardo and his colleagues in the Royal Society journal Notes and Records, according to Nature.

The minor changes Galileo made did not successfully hold off the Church’s crackdown on heliocentrism. In 1616, the Inquisition ordered Galileo to stop teaching or defending the theory, and several of his books were subsequently banned. He would stand trial again almost two decades later, in 1633, on suspicion of holding heretical thoughts. He was found guilty and sentenced to house arrest, where he remained until his death in 1642.

[h/t Ars Technica]

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