Psychologists find more sensitive tests for predicting Alzheimer's as well as changes in cognition
Implicit-memory tests are stronger predictors than the common Mini Mental exam; Alzheimer's may hurt attention well before obvious memory loss.
Two recent studies may help clinicians and researchers better predict and understand dementia of the Alzheimer's type early in its history. Both studies appear in the September issue of Neuropsychology, which is published by the American Psychological Association (APA). Psychologists focus on early detection in part because current medications are useful only when given very early in the course of the disease.
In the first study, psychologists Pauline Spaan, PhD, and Jeroen Raaijmakers, PhD, from the University of Amsterdam in collaboration with neurologist Cees Jonker, MD, PhD, from the Vrije Universiteit in Amsterdam analyzed the data on 119 participants in the Longitudinal Aging Study Amsterdam, a large, population-based study of older people. The researchers visited older people in their homes and gave them memory tests loaded on laptop computers. Two years later, they compared the test scores of people who went on to develop Alzheimer's with the scores of those who stayed healthy.
The researchers analyzed memory components that included episodic (what happened; what did you hear or read); semantic (vocabulary, facts); and implicit (learning without awareness of learning, "priming"). Three tests were very good at predicting who would develop Alzheimer's by two years later. Participants for whom "priming" information didn't aid memory or whose learning wasn't aided by semantic knowledge -- were significantly more likely to develop Alzheimer's.
We Are the Web
The Netscape IPO wasn't really about dot-commerce. At its heart was a new cultural force based on mass collaboration. Blogs, Wikipedia, open source, peer-to-peer - behold the power of the people.
Ten years ago, Netscape's explosive IPO ignited huge piles of money. The brilliant flash revealed what had been invisible only a moment before: the World Wide Web. As Eric Schmidt (then at Sun, now at Google) noted, the day before the IPO, nothing about the Web; the day after, everything.
Computing pioneer Vannevar Bush outlined the Web's core idea - hyperlinked pages - in 1945, but the first person to try to build out the concept was a freethinker named Ted Nelson who envisioned his own scheme in 1965. However, he had little success connecting digital bits on a useful scale, and his efforts were known only to an isolated group of disciples. Few of the hackers writing code for the emerging Web in the 1990s knew about Nelson or his hyperlinked dream machine.
At the suggestion of a computer-savvy friend, I got in touch with Nelson in 1984, a decade before Netscape. We met in a dark dockside bar in Sausalito, California. He was renting a houseboat nearby and had the air of someone with time on his hands. Folded notes erupted from his pockets, and long strips of paper slipped from overstuffed notebooks. Wearing a ballpoint pen on a string around his neck, he told me - way too earnestly for a bar at 4 o'clock in the afternoon - about his scheme for organizing all the knowledge of humanity. Salvation lay in cutting up 3 x 5 cards, of which he had plenty.
Although Nelson was polite, charming, and smooth, I was too slow for his fast talk. But I got an aha! from his marvelous notion of hypertext. He was certain that every document in the world should be a footnote to some other document, and computers could make the links between them visible and permanent. But that was just the beginning! Scribbling on index cards, he sketched out complicated notions of transferring authorship back to creators and tracking payments as readers hopped along networks of documents, what he called the docuverse. He spoke of "transclusion" and "intertwingularity" as he described the grand utopian benefits of his embedded structure. It was going to save the world from stupidity.
I believed him. Despite his quirks, it was clear to me that a hyperlinked world was inevitable - someday. But looking back now, after 10 years of living online, what surprises me about the genesis of the Web is how much was missing from Vannevar Bush's vision, Nelson's docuverse, and my own expectations. We all missed the big story. The revolution launched by Netscape's IPO was only marginally about hypertext and human knowledge. At its heart was a new kind of participation that has since developed into an emerging culture based on sharing. And the ways of participating unleashed by hyperlinks are creating a new type of thinking - part human and part machine - found nowhere else on the planet or in history.
Not only did we fail to imagine what the Web would become, we still don't see it today! We are blind to the miracle it has blossomed into. And as a result of ignoring what the Web really is, we are likely to miss what it will grow into over the next 10 years. Any hope of discerning the state of the Web in 2015 requires that we own up to how wrong we were 10 years ago.
The new science of race
Henry Harpending is about to titillate the world's conspiracy theorists with one of the most politically incorrect academic papers of the new millennium.
Why, he and his colleagues at the University of Utah asked, have Jews of European descent won 27 per cent of the Nobel Prizes given to Americans in the past century, while making up only 3 per cent of the population? Why do they produce more than half the world's chess champions? And why do they have an average IQ higher than any other ethnic group for which there's reliable data, and nearly six times as many people scoring above 140 compared with Europeans?
Prof. Harpending suggests that the reason is in their bloodline — it's genetic.
The 61-year-old anthropologist's explanation is not easily dismissed, but it crosses into the territory scientists fear most.
"Cogent Confabulation"
A leading expert in artificial intelligence and neural networks argues that cognition in humans and many animals occurs in a very different, non-algorithmic and less complex way than has been widely assumed until now.
Robert Hecht-Nielsen, an adjunct professor in electrical and computer engineering at the University of California, San Diego’s Jacobs School of Engineering, has also been a vice president of R&D at Fair Isaac Corporation since the company acquired a software firm he co-founded, HNC Software. He outlined his theory of the fundamental mechanism of cognition in a seminar on the UCSD campus yesterday, and details appear in the February issue of the journal Neural Networks, in an article titled “Cogent Confabulation.”
Sharper Minds
It would be hard to imagine improving on the intelligence of computer engineer Bjoern Stenger, a doctoral candidate at Cambridge University. Yet for several hours, a pill seemed to make him even brainier.
Participating in a research project, Stenger downed a green gelatin cap containing a drug called modafinil. Within an hour, his attention sharpened. So did his memory. He aced a series of mental-agility tests. If his brainpower would normally rate a 10, the drug raised it to 15, he said.
"I was quite focused," said Stenger. "It was also kind of fun."
The age of smart drugs is dawning. Modafinil is just one in an array of brain-boosting medications — some already on pharmacy shelves and others in development — that promise an era of sharper thinking through chemistry.
These drugs may change the way we think. And by doing so, they may change who we are.
Long-haul truckers and Air Force pilots have long popped amphetamines to ward off drowsiness. Generations of college students have swallowed over-the-counter caffeine tablets to get through all-nighters. But such stimulants provide only a temporary edge, and their effect is broad and blunt — they boost the brain by juicing the entire nervous system.
The new mind-enhancing drugs, in contrast, hold the potential for more powerful, more targeted and more lasting improvements in mental acuity. Some of the most promising have reached the stage of testing in human subjects and could become available in the next decade, brain scientists say.
Apply Current, Boost Brain Power
Sending a weak electrical impulse through the front of a person's head can boost verbal skills by as much as 20 percent, according to a new study by the U.S. National Institute of Neurological Disorders and Stroke.
In the study, researchers at the institute asked 103 volunteers to recall as many words that begin with a particular letter as possible. The researchers then passed a 2-milliamp current -- one-tenth of what is needed to power a small LED (light-emitting diode) light -- through electrodes attached to the surfaces of the volunteers' foreheads. When the volunteers were quizzed again while the current was still on, this time with a different letter, they were able to come up with 20 percent more words on average.
The Wisdom of Crowds
Why the Many Are Smarter Than the Few and How Collective Wisdom Shapes Business, Economies, Societies, and Nations
In the summer of 2003, analysts at the Department of Defense had an unusual idea. To predict important events in the world, including terrorist attacks, they would create a kind of market in which ordinary people could actually place bets. The proposed Policy Analysis Market would allow each of us to invest in our predictions about such matters as the growth of the Egyptian economy, the death of Yasir Arafat, and the likelihood of terrorist attacks in the United States. Investors would win or lose money on the basis of the accuracy of their predictions. Predictably, the Policy Analysis Market produced a storm of criticism. Ridiculed as "offensive" and "useless," the proposal was abandoned.
Amid the war on terrorism, why was the Defense Department so interested in the Policy Analysis Market? The answer is simple: it wanted to have some help in predicting geopolitical events, including those that would endanger American interests, and it believed that a market would provide that help. It speculated that if a large number of people could be given an incentive to aggregate their private information, in the way that the Policy Analysis Market would do, government officials would learn a great deal.
Does this idea seem ludicrous? Since 1988, the University of Iowa has run the Iowa Electronic Markets, which allow people to bet on the outcome of presidential elections. As a predictor, the Iowa Electronic Markets have produced extraordinarily accurate judgments, often doing better than professional polling organizations. In the week before each of the last four elections, the predictions in the Iowa market have shown an average absolute error of just 1.5 percentage points, a significant improvement over the 2.1 percentage point error in the final Gallup Polls. Or consider the Hollywood Stock Exchange, in which people predict Oscar nominees and winners, as well as opening weekend box-office successes. Here, too, the level of accuracy has been exceptionally impressive, with (for example) correct predictions of thirty-five out of forty Oscar nominees in 2002.
In fact, prediction markets are springing up all over the Internet, allowing people to make bets on the likely outcomes of sports, entertainment, finance, and political events. On tradesports.com, people have been betting on whether Donald Rumsfeld will resign soon (extremely unlikely), whether Osama bin Laden will be captured by June 2004 (extremely unlikely), whether John Edwards will be selected as John Kerry's running mate (a good chance, but probably not), and whether George W. Bush will be re-elected (more likely than not). One can imagine prediction markets on any number of questions: Will gas prices reach $3 per gallon? Will cellular life be found on Mars? Will smallpox return to the United States? Will there be a sequel to Master and Commander? Will the Federal Communications Commission be abolished? (I didn't make these up; they are actual or proposed questions on existing markets.)
James Surowiecki is fascinated by prediction markets. In his opinion, they demonstrate that crowds are often wise. He rejects the widespread view that groups of ordinary people are usually wrong--and that we do better to ignore them and follow experts instead. Even when individuals blunder, he believes, groups can excel: "Under the right circumstances, groups are remarkably intelligent, and are often smarter than the smartest people in them." This is so even when "most of the people within the group are not especially well-informed or rational." What is wonderful, and surprising, is that "when our imperfect judgments are aggregated in the right way, our collective intelligence is often excellent." Instead of chasing experts, we should consult that collective intelligence.
Hierarchical Complexity Scoring System
The Model of Hierarchical Complexity presents a framework for scoring reasoning stages in any domain as well as in any cross cultural setting. The scoring is based not upon the content or the subject material, but instead on the mathematical complexity of hierarchical organization of information. The subject’s performance on a task of a given complexity represents the stage of developmental complexity.
Cracked Bell
The Bell Curve: Intelligence and Class Structure in American Life, by Richard J. Herrnstein and Charles Murray, New York: The Free Press, 845 pages
Charles Murray and the late Richard Herrnstein have produced a controversial and well-written book about human differences, the sources of human differences, and how we should respond to those differences. The early reactions to the book in the popular press have been emotional and denunciatory, focusing almost exclusively on the authors' discussion of racial differences and the genetic basis for those differences. This is unfortunate. The book is not devoted exclusively to a discussion of racial differences, although it certainly considers them in detail. It is obvious that most reviewers of the book have not read it as a whole, if they have read it at all. It is also clear that in an age of rampant egalitarianism, discussion of differences in cognitive skills remains taboo. The authors deserve much praise for discussing a forbidden subject and thereby initiating a public discussion that challenges the egalitarian presumptions of our day.
We don't see things as they are, we see things as we are.
We don't see things as they are, we see things as we are.
- Anais Nin
Educate for multiple intelligences
"Psychology really has had two big impacts on society," Harvard University
psychologist Howard Gardner told a packed lecture room at Teachers College,
Columbia University, Tokyo on June 8. "The first has been in advertising--mind
manipulation--and the other has been intelligence testing."
Gardner, who was on a weeklong speaking tour in Tokyo, criticized the
traditional view of intelligence as that of a single factor, largely inherited
Greg Smith's web site
Gene Enhances Prefrontal Function At A Price
Studies of a gene that affects how efficiently the brain's frontal lobes process information are revealing some untidy consequences of a tiny variation in its molecular structure and how it may increase susceptibility to schizophrenia. People with a common version of the gene associated with more efficient working memory and frontal lobe information processing may pay a penalty in adverse responses to amphetamine, in heightened anxiety and sensitivity to pain. Yet, another common version may slightly bias the brain toward a pattern of neurochemical activity associated with psychosis, report researchers at the National Institutes of Health (NIH).
The real problem is not whether machines think but whether men do.
The real problem is not whether machines think but whether men do.
- Burrhus Frederic Skinner
