Bilingualism, brain health, and mental training

In America, we live in one of the few countries where most of the population is exclusively monolingual. Bilingualism and multilingualism are more the human norm. Jared Diamond writes, in The Benefits of Multilingualism (Science, 330:6002 (15 October 2010), 332-333.):

Multilingualism—the ability to understand and speak several languages—is exceptional in the United States but common elsewhere, especially in small-scale traditional societies. For instance, once while I was camped with some New Guinea Highlanders conversing simultaneously in several local languages, I asked each man to name each language in which he could converse. It turned out that everyone present spoke at least 5 languages, and the champion was a man who spoke 15. What are the cognitive effects of such multilingualism? Recent studies (1–5) show that children raised bilingually develop a specific type of cognitive benefit during infancy, and that bilingualism offers some protection against symptoms of Alzheimer's dementia in old people.

...Our minds are assaulted by varied sights, sounds, and other external sensory inputs, plus thoughts and proprioreceptive sensations (which make us aware of the relative positions of our own body parts) (see the figure). To succeed in doing anything at all, we must temporarily inhibit 99% of those inputs and attend to just 1% of them, and the appropriate choice varies with the circumstances. That selective attention involves a set of processes, termed executive function, that reside in the prefrontal cortex and develop especially over the first 5 years of life.

Multilingual people have a special challenge involving executive function. Monolinguals hearing a word need only compare it with their single stock of arbitrary phoneme (sound) and meaning rules, and when uttering a word they draw it from that single stock. ...Multilinguals participating in a multilingual conversation...switch frequently and unpredictably between their stocks of phoneme/meaning rules. As a result, multilinguals have constant unconscious practice in using the executive function system.

Such pervasive multilingualism can cause enormous cross-pollination and "covergent evolution" in languages. Bill Foley says, in More on Papuan Languages:

Somewhere close to a quarter of the total of the world's languages are spoken in the New Guinea region-about 1100 languages. ...The small size of many Papuan speaking speech communities has often led to persistent multilingualism in the language of adjoining communities, the development of trade jargons for interlanguage communication or the shifting of language allegiance to languages of more powerful or economically advantaged neighbours. In such a complex, fragmented linguistic situation, Papuan languages not unexpectedly exhibit a pattern of enormous cross-influence in all areas. All types of linguistic features, basic vocabulary, pronouns, grammatical patterns, discourse styles can be and have been borrowed from one language into another. This makes the establishment of genetic links among Papuan languages doubly difficult: with no documentation for the vast majority of them older than 50 years, it is problematic indeed to sift what is true genetically inherited material from what is borrowed from other languages, especially borrowing from genetically related contiguous languages or borrowings centuries old from now deceased languages.

Diamond cites the research of Ellen Bialystok; LanguageLog and languagehat point us to The Bilingual Advantage, a Q&A with Bialystok at the NYT:

Q. One of your most startling recent findings is that bilingualism helps forestall the symptoms of Alzheimer’s disease. How did you come to learn this?

A. We did two kinds of studies. In the first, published in 2004, we found that normally aging bilinguals had better cognitive functioning than normally aging monolinguals. Bilingual older adults performed better than monolingual older adults on executive control tasks. That was very impressive because it didn’t have to be that way. It could have turned out that everybody just lost function equally as they got older.

That evidence made us look at people who didn’t have normal cognitive function. In our next studies , we looked at the medical records of 400 Alzheimer’s patients. On average, the bilinguals showed Alzheimer’s symptoms five or six years later than those who spoke only one language. This didn’t mean that the bilinguals didn’t have Alzheimer’s. It meant that as the disease took root in their brains, they were able to continue functioning at a higher level. They could cope with the disease for longer.

Which reminds me somewhat of the Gizmodo post How to Make Yourself Smarter in 20 Days, which highlights the use of n-back mental training exercises for 20 minutes a day for 20 days to increase fluid intelligence for three months. Not that I've tried it, but Brain Workshop vaguely reminds me of electronic flashcards and spaced repetition software like Anki, for memorization. Executive control, fluid intelligence, and vocabulary memorization are all very different, but it seems like 20 minutes a day of abstract memory practice would get pretty boring, and something language-related may be more interesting.

EDIT
Brain Calisthenics for Abstract Ideas (NYT)

The 11th day of Winter

The winter solstice is, technically, not the shortest day of the year, but the brief instant at which the Earth's axial tilt is farthest away from the sun; this occurred on Dec. 21, at 17:47 UTC. More colloquially, it is the day on which this instant occurs, which is commonly known as the first day of winter. So, today is the 11th day of Winter. The solstice can occur at varying times; in 2006, it happened 22 minutes after midnight UTC, according to the USNO. The solstice being an instant rather than a day can be a source of some confusion, as when pagans celebrate the solstice on the wrong day, showing up at Stonehenge a day early (since it seems Stonehenge observes the first sunrise after the moment of the solstice).

Measuring this precise moment is difficult for non-astronomers, but ancient peoples built many structures aligned with the changing position of the rising or setting sun throughout the year. The summer solstice is easier to determine using their methods than the winter, because around the winter solstice, the "sun stands still". More modern instruments can use this phenomena, the analemma, in an analemma calendar.

This New Year's Eve will also see the second full moon in the month of December, a "blue moon" (1, 2, 3, 4). The next winter solstice, on December 21, 2010, will feature a total lunar eclipse visible in all stages throughout North America.

I reckon everyone will celebrate the end of the Aughties tonight, since 2010 begins in a few hours. Of course, the 10th year is the final year in a set of ten years; 2010 is the last year of the first decade of the 21st century, and the second decade begins in 2011. We begin counting with the number 1, not the number zero. But the common parlance will have tonight as the end of the Aughties, and (not being a fan of the decade) I'd say we should move on to a new one sooner than later.

Happy New Year!

A River of Stars in a Dark Sky

In Japanese, the Milky Way is known as "天の川 (あまのがわ)", the River of Heaven, because it appears as a mighty river of stars flowing through the night sky. Every summer, people celebrate "Tanabata", a festival that recognizes this phenomena.

Long ago, there was a princess named Vega, who was the daughter of the king of heaven. Every day, she went to the banks of the Milky Way River to weave clothes for her father. But since she worked so hard, she was very lonely. One day, she met a cowboy tending his herd on the other side of the river. His name was Altair, and they fell in love and soon got married. But after they were married, the princess didn't weave clothes for her father, and the cowboy let his animals wander all over the sky. This made Vega's father angry, so he banished Altair to the other side of the river to separate the couple. Each of the pair could only sit on opposite sides of the river and look wistfully at each other. But on one night every year, on the seventh night of the seventh month, the pair of stars are allowed to meet one another, since a flock of magpies agreed to form a bridge over the river with their wings.

This phenomena is hard to see, because of pervasive light pollution in the developed world, the extent of which is apparent in maps of Earth's city lights. In most cities, light pollution is so severe that only the very brightest starts are faintly visible, while in truly dark areas, the light of the Milky Way can cast a visible shadow.

The International Dark Sky Association advocates against light pollution. There are a few locations in the eastern US designated as a dark sky preserve, including Cherry Springs State Park in northern Pennsylvania. The park has annual star parties that attract hundreds of astronomers, which began in the late 1990s when individual hobbyists noticed an isolated black patch on nighttime satellite photos.

Similar maps can be seen at the World Atlas of Artificial Night Sky Brightness. One of the largest patches of dark skies in the eastern US appears to be in eastern West Virginia in the Monongahela National Forest. This area is the heart of the National Radio Astronomy Observatory, which has the world's largest fully steerable radio telescope in a radio quiet zone at Green Bank, WV.

For nearer places, the DarkSky Finder is a Java application that works in Firefox. Near Louisville, the darkest sites are southwest of Leavenworth, IN, in the southeastern portion of the Hoosier National Forest and across the river in the corresponding section of Kentucky. There is a slightly darker area immediately west of Hazard, KY, around Buckhorn Lake (an area with a high incidence of communities with interesting names). There are some maps and brochures of the Daniel Boone National Forest for this area; the Redbird Crest Trail, especially the eastern side, is in the middle of this dark spot. The topo maps could useful as well; 17 is Buckhorn Lake; 44 shows the area around Thousandsticks west of Hyden; and the Redbird Crest Trail is on 11 and 28, centered on Creekville.