Well: Ask Well: Squats for Aging Knees

You are already doing many things right, in terms of taking care of your aging knees. In particular, it sounds as if you are keeping your weight under control. Carrying extra pounds undoubtedly strains knees and contributes to pain and eventually arthritis.

You mention weight training, too, which is also valuable. Sturdy leg muscles, particularly those at the front and back of the thighs, stabilize the knee, says Joseph Hart, an assistant professor of kinesiology and certified athletic trainer at the University of Virginia, who often works with patients with knee pain.

An easy exercise to target those muscles is the squat. Although many of us have heard that squats harm knees, the exercise is actually “quite good for the knees, if you do the squats correctly,” Dr. Hart says. Simply stand with your legs shoulder-width apart and bend your legs until your thighs are almost, but not completely, parallel to the ground. Keep your upper body straight. Don’t bend forward, he says, since that movement can strain the knees. Try to complete 20 squats, using no weight at first. When that becomes easy, Dr. Hart suggests, hold a barbell with weights attached. Or simply clutch a full milk carton, which is my cheapskate’s squats routine.

Straight leg lifts are also useful for knee health. Sit on the floor with your back straight and one leg extended and the other bent toward your chest. In this position, lift the straight leg slightly off the ground and hold for 10 seconds. Repeat 10 to 20 times and then switch legs.

You can also find other exercises that target the knees in this video, “Increasing Knee Stability.”

Of course, before starting any exercise program, consult a physician, especially, Dr. Hart says, if your knees often ache, feel stiff or emit a strange, clicking noise, which could be symptoms of arthritis.

Read More..

Well: Ask Well: Squats for Aging Knees

You are already doing many things right, in terms of taking care of your aging knees. In particular, it sounds as if you are keeping your weight under control. Carrying extra pounds undoubtedly strains knees and contributes to pain and eventually arthritis.

You mention weight training, too, which is also valuable. Sturdy leg muscles, particularly those at the front and back of the thighs, stabilize the knee, says Joseph Hart, an assistant professor of kinesiology and certified athletic trainer at the University of Virginia, who often works with patients with knee pain.

An easy exercise to target those muscles is the squat. Although many of us have heard that squats harm knees, the exercise is actually “quite good for the knees, if you do the squats correctly,” Dr. Hart says. Simply stand with your legs shoulder-width apart and bend your legs until your thighs are almost, but not completely, parallel to the ground. Keep your upper body straight. Don’t bend forward, he says, since that movement can strain the knees. Try to complete 20 squats, using no weight at first. When that becomes easy, Dr. Hart suggests, hold a barbell with weights attached. Or simply clutch a full milk carton, which is my cheapskate’s squats routine.

Straight leg lifts are also useful for knee health. Sit on the floor with your back straight and one leg extended and the other bent toward your chest. In this position, lift the straight leg slightly off the ground and hold for 10 seconds. Repeat 10 to 20 times and then switch legs.

You can also find other exercises that target the knees in this video, “Increasing Knee Stability.”

Of course, before starting any exercise program, consult a physician, especially, Dr. Hart says, if your knees often ache, feel stiff or emit a strange, clicking noise, which could be symptoms of arthritis.

Read More..

DealBook: Jefferies C.E.O. Earned $19 Million in 2012

3:48 p.m. | Updated

The head of the Jefferies Group was one of the better-paid chief executives on Wall Street in 2012, as the firm put a difficult period behind it.

Richard B. Handler, the chief executive of Jefferies, earned a total of $19 million for 2012, the firm said in a filing on Tuesday. That included a $5 million cash bonus and a $13 million long-term equity incentive award, on top of a $1 million base salary.

The board’s compensation committee was “unanimously impressed with our financial performance and Mr. Handler’s role in that performance,” Jefferies said in the filing. The board said that Mr. Handler was eligible for a bonus of $8.1 million but volunteered to take a smaller amount.

Jefferies reported a profit of $71.6 million in the fourth quarter, an increase of 48 percent from a year earlier. It was the final independent earnings report for the boutique investment bank, which is becoming part of the Leucadia National Corporation in a $3.6 billion deal. Mr. Handler is set to become Leucadia’s chief executive.

Jefferies said in the filing on Tuesday that Mr. Handler was also granted restricted stock worth $39 million to cover three future years: 2013, 2014 and 2015.

Mr. Handler’s pay package for 2012 was higher than that of Jamie Dimon, head of JPMorgan Chase. Mr. Dimon earned $11.5 million, compared with $23 million a year earlier.

Mr. Handler got a significant raise from 2011, when he earned $14 million. That year, he declined to accept a bonus after a period in which investors feared for the firm’s health.

But those fears, which emerged in the wake of MF Global‘s collapse, appear to have largely receded. The firm’s shares rose about 35 percent in 2012 and were virtually flat on Tuesday.

Read More..

The Lede Blog: Fire at a Nightclub in Southern Brazil

Medics in Brazil rushed to care for the victims of a deadly fire at a nightclub on Sunday.

Last Updated, Monday, 3:36 p.m. An intense fire ripped through a nightclub crowded with university students in southern Brazil early on Sunday morning, leaving behind a scene of horror, with bodies piled in the club’s bathrooms and on the street. At least 233 people were killed, many of them students in the agronomy and veterinary medicine programs at a local university, police officials said. By Sunday evening, the authorities had released a preliminary list of the dead.

As Simon Romero reports, a flare from a band’s pyrotechnic show ignited the fire in the nightclub, called Kiss, in the southern city of Santa Maria. Rescue workers continued to haul bodies from the still-smoldering building on Sunday.

Extremely disturbing video uploaded to YouTube by witnesses showed scenes of chaos in a makeshift morgue and on the street outside, as medics scurried over the bodies of victims who appeared to be unconscious, checking for signs of life.

Victims of the fire are attended by medics — this video contains very disturbing images.

Officials and witnesses say that security guards at the club had locked some exits, sowing panic as people attempted to flee the flames and smoke.

“Only after a multitude pushed down the security guards did they see the crap they had done,” Murilo de Toledo Tiecher, 26, a medical student who survived the fire, said in comments posted on Facebook.

Shortly before the fire, a club D.J. posted a photo on Facebook from inside the crowded club apparently showing the pyrotechnic display on stage.

A short time later, another photo that was said to be taken outside the club and widely disseminated through social media showed smoke billowing from the front entrance.

The fire quickly engulfed the building.

Firefighters and volunteers who used T-shirts to protect themselves from the smoke struggled to pull people from the burning building.

Firefighters and volunteers tried to pull people from the burning building

Photos from the scene showed frantic friends and family members gathered outside the club and a hospital.

As Mr. Romero reports, witnesses said the fire started about 2 a.m. after the band, Gurizada Fandangueira, took the stage. At least one member of the five-person band, which is based in Santa Maria and advertised its use of pyrotechnics, was said to have been killed in the fire.

In a statement posted on its Facebook page, the nightclub said that its operations are on hold and that it would assist the authorities with an investigation. “We would still like to reiterate that our staff has the highest technical qualifications and was properly trained and prepared for any contingency,” it added.

Overcrowding and a disregard for fire safety codes have led to deadly blazes at nightclubs in the past, though Sunday’s tragedy in Brazil is among the worst.

In 2003 in Rhode Island, also fire set off by a pyrotechnic display at a club killed about 100 people. A fire that erupted under similar circumstances in Russia left almost as many dead in 2009.

And in Luoyang, China in 2000, 309 people were killed in a fire that broke out at a dance hall, forcing some to leap from high-rise windows.



This post has been revised to reflect the following correction:

Correction: January 28, 2013

An earlier version of this post included video of a fire that was not recorded in Brazil on Sunday, but had been mislabeled and uploaded to a fake BBC News channel on YouTube.

Read More..

TIMESCAST: Changes Unveiled at The New Republic

January 28, 2013

TimesCast Media+Tech: The right to unlock cellphones expires. | Chris Hughes, publisher of The New Republic, discusses its redesign. | An animated look at how technology may change our daily routines.

Read More..

Well: Keeping Blood Pressure in Check

Since the start of the 21st century, Americans have made great progress in controlling high blood pressure, though it remains a leading cause of heart attacks, strokes, congestive heart failure and kidney disease.

Now 48 percent of the more than 76 million adults with hypertension have it under control, up from 29 percent in 2000.

But that means more than half, including many receiving treatment, have blood pressure that remains too high to be healthy. (A normal blood pressure is lower than 120 over 80.) With a plethora of drugs available to normalize blood pressure, why are so many people still at increased risk of disease, disability and premature death? Hypertension experts offer a few common, and correctable, reasons:


Jane Brody speaks about hypertension.




¶ About 20 percent of affected adults don’t know they have high blood pressure, perhaps because they never or rarely see a doctor who checks their pressure.

¶ Of the 80 percent who are aware of their condition, some don’t appreciate how serious it can be and fail to get treated, even when their doctors say they should.

¶ Some who have been treated develop bothersome side effects, causing them to abandon therapy or to use it haphazardly.

¶ Many others do little to change lifestyle factors, like obesity, lack of exercise and a high-salt diet, that can make hypertension harder to control.

Dr. Samuel J. Mann, a hypertension specialist and professor of clinical medicine at Weill-Cornell Medical College, adds another factor that may be the most important. Of the 71 percent of people with hypertension who are currently being treated, too many are taking the wrong drugs or the wrong dosages of the right ones.

Dr. Mann, author of “Hypertension and You: Old Drugs, New Drugs, and the Right Drugs for Your High Blood Pressure,” says that doctors should take into account the underlying causes of each patient’s blood pressure problem and the side effects that may prompt patients to abandon therapy. He has found that when treatment is tailored to the individual, nearly all cases of high blood pressure can be brought and kept under control with available drugs.

Plus, he said in an interview, it can be done with minimal, if any, side effects and at a reasonable cost.

“For most people, no new drugs need to be developed,” Dr. Mann said. “What we need, in terms of medication, is already out there. We just need to use it better.”

But many doctors who are generalists do not understand the “intricacies and nuances” of the dozens of available medications to determine which is appropriate to a certain patient.

“Prescribing the same medication to patient after patient just does not cut it,” Dr. Mann wrote in his book.

The trick to prescribing the best treatment for each patient is to first determine which of three mechanisms, or combination of mechanisms, is responsible for a patient’s hypertension, he said.

¶ Salt-sensitive hypertension, more common in older people and African-Americans, responds well to diuretics and calcium channel blockers.

¶ Hypertension driven by the kidney hormone renin responds best to ACE inhibitors and angiotensin receptor blockers, as well as direct renin inhibitors and beta-blockers.

¶ Neurogenic hypertension is a product of the sympathetic nervous system and is best treated with beta-blockers, alpha-blockers and drugs like clonidine.

According to Dr. Mann, neurogenic hypertension results from repressed emotions. He has found that many patients with it suffered trauma early in life or abuse. They seem calm and content on the surface but continually suppress their distress, he said.

One of Dr. Mann’s patients had had high blood pressure since her late 20s that remained well-controlled by the three drugs her family doctor prescribed. Then in her 40s, periodic checks showed it was often too high. When taking more of the prescribed medication did not result in lasting control, she sought Dr. Mann’s help.

After a thorough work-up, he said she had a textbook case of neurogenic hypertension, was taking too much medication and needed different drugs. Her condition soon became far better managed, with side effects she could easily tolerate, and she no longer feared she would die young of a heart attack or stroke.

But most patients should not have to consult a specialist. They can be well-treated by an internist or family physician who approaches the condition systematically, Dr. Mann said. Patients should be started on low doses of one or more drugs, including a diuretic; the dosage or number of drugs can be slowly increased as needed to achieve a normal pressure.

Specialists, he said, are most useful for treating the 10 percent to 15 percent of patients with so-called resistant hypertension that remains uncontrolled despite treatment with three drugs, including a diuretic, and for those whose treatment is effective but causing distressing side effects.

Hypertension sometimes fails to respond to routine care, he noted, because it results from an underlying medical problem that needs to be addressed.

“Some patients are on a lot of blood pressure drugs — four or five — who probably don’t need so many, and if they do, the question is why,” Dr. Mann said.


How to Measure Your Blood Pressure

Mistaken readings, which can occur in doctors’ offices as well as at home, can result in misdiagnosis of hypertension and improper treatment. Dr. Samuel J. Mann, of Weill Cornell Medical College, suggests these guidelines to reduce the risk of errors:

¶ Use an automatic monitor rather than a manual one, and check the accuracy of your home monitor at the doctor’s office.

¶ Use a monitor with an arm cuff, not a wrist or finger cuff, and use a large cuff if you have a large arm.

¶ Sit quietly for a few minutes, without talking, after putting on the cuff and before checking your pressure.

¶ Check your pressure in one arm only, and take three readings (not more) one or two minutes apart.

¶ Measure your blood pressure no more than twice a week unless you have severe hypertension or are changing medications.

¶ Check your pressure at random, ordinary times of the day, not just when you think it is high.

Read More..

An Italian Bank Caught in the Vortex of Election Politics


MILAN — The chief executive of a regional Italian bank embroiled in a scandal with political and even Europe-wide implications said Monday that recent revelations of past mismanagement and questionable deals would not impede efforts to turn around the beleaguered institution.


“This is still a solid bank,” Fabrizio Viola, chief executive of Monte dei Paschi di Siena, said Monday at a news conference in Milan.


In the past week revelations of transactions that may have disguised the extent of the bank’s losses during the global financial crisis have become political fodder ahead of Italy’s national elections next month.


And the disclosures have raised questions about the degree of scrutiny given Monte dei Paschi di Siena by Mario Draghi, who was still head of Italy’s central bank when the problems developed. Mr. Draghi, of course, is now president of the European Central Bank.


At issue is whether Monte dei Paschi di Siena, or M.P.S. as it is known, hid losses it incurred after acquiring the Italian bank Antonveneta in 2008, for €9 billion — a price that even at the time was widely derided as far too high. Now under scrutiny are two complex transactions M.P.S. conducted with Deutsche Bank and Nomura that critics say enabled M.P.S. to mask some of its losses.


Mr. Viola, part of the new management that came to the bank last year, said Monday that an investigation now under way would produce findings by mid-February, ahead of national elections scheduled for Feb. 24 and 25.


With M.P.S. based in Siena, in a part of northern Italy that is a stronghold of the leftist Democratic Party, the conservative former prime minister Silvio Berlusconi, who is trying to be a spoiler in next month’s elections, has been trying to lay blame for the scandal at the Democratic Party’s doorstep. Meanwhile, the current prime minister, Mario Monti, has had to defend his government’s decision to bail out the banks with loans granted last year.


More broadly, though, the problems at M.P.S. provide an extreme example of an old-line banking pattern that analysts say is still disturbingly commonplace in Europe. As with most Italian banks, M.P.S.’s primary shareholder is a local foundation, which receives dividends that are to be used to pay for social projects as well as cultural and charitable enterprises. That gives M.P.S. an extensive veil of political relationships that can be hard for any national overseer to peer through.


The same combination of local political influence and lax control has also afflicted many banks in Germany and Spain, with taxpayers left suffering the consequences. Indeed, grave lapses by national regulators are among the main reasons European leaders have decided to put the European Central Bank in charge of bank regulation.


But now there is a possible snag in the plan: Mr. Draghi, who is expected to lead that overhaul, was at least nominally the overseer of M.P.S. while it was digging itself into a deep hole.


Many analysts, though, question whether Mr. Draghi — or any Italian regulators — would have had enough information to recognize the bank’s problems, since there appears to have been a deliberate attempt to conceal losses. And in any case, the Bank of Italy may not have had legal power to prevent M.P.S. from making bad decisions.


But at the very least Mr. Draghi’s proximity to the scandal is untimely as the E.C.B. and euro zone leaders finally seemed to be rebuilding credibility in the common currency. The decision to create a centralized banking supervisor at the E.C.B. is a big part of the effort to restore confidence in the euro zone.


“Italy is a country where even national regulators can have a trouble getting a grip on what is happening at the local level,” said Nicolas Véron, a senior fellow at Bruegel, a research organization in Brussels. Mr. Véron stressed that there was no evidence Mr. Draghi deserved any blame for the Monti dei Paschi scandal.


But Mr. Véron said, “It clearly does create perception problems, because there’s a question mark about the appropriateness of the Bank of Italy’s response at the time.”


“At this point it’s only a question mark,” Mr. Véron said. “We don’t have any facts.”


A spokesman for the E.C.B. declined to comment Monday.


Read More..

The Lede Blog: Fire at a Nightclub in Southern Brazil

Victims of the fire are attended by medics.

An intense fire ripped through a nightclub crowded with university students in southern Brazil early on Sunday morning, leaving behind a scene of horror, with bodies piled in the club’s bathrooms and on the street.

At least 232 people were killed, many of them students in the agronomy and veterinary medicine programs at a local university, police officials said.

As Simon Romero reports, a flare from a band’s pyrotechnic show ignited the fire in the nightclub, called Kiss, in the southern city of Santa Maria. Rescue workers continued to haul bodies from the still-smoldering building on Sunday.

Amateur videos posted to YouTube showed scenes of chaos as medics scurried over the bodies of victims who appeared to be unconscious, checking for signs of life.

Medics rush to care for victims of the fire.

Officials and witnesses say that security guards at the club had locked some exits, sewing panic as people attempted to flee the flames and smoke.

“Only after a multitude pushed down the security guards did they see the crap they had done,” Murilo de Toledo Tiecher, 26, a medical student who survived the fire, said in comments posted on Facebook.

Shortly before the fire, a club D.J. posted a photo on Facebook from inside the crowded club apparently showing the pyrotechnic display on stage.

A short time later, another photo that was said to be taken outside the club and widely disseminated through social media showed smoke billowing from the front entrance.

The fire quickly engulfed the building.

Firefighters and volunteers who used T-shirts to protect themselves from the smoke struggled to pull people from the burning building.

Firefighters and volunteers tried to pull people from the burning building

Photos from the scene showed frantic friends and family members gathered outside the club and a hospital.

As Mr. Romero reports, witnesses said the fire started about 2 a.m. after the band, Gurizada Fandangueira, took the stage. At least one member of the five-person band, which is based in Santa Maria and advertised its use of pyrotechnics, was said to have been killed in the fire.

Overcrowding and a disregard for fire safety codes have led to deadly blazes at nightclubs in the past, though Sunday’s tragedy in Brazil is among the worst.

In 2003 in Rhode Island, also fire set off by a pyrotechnic display at a club killed about 100 people. A fire that erupted under similar circumstances in Russia left almost as many dead in 2009.

And in Luoyang, China in 2000, 309 people were killed in a fire that broke out at a dance hall, forcing some to leap from high-rise windows.


Read More..

Unboxed: Literary History, Seen Through Big Data’s Lens





ANY list of the leading novelists of the 19th century, writing in English, would almost surely include Charles Dickens, Thomas Hardy, Herman Melville, Nathaniel Hawthorne and Mark Twain.




But they do not appear at the top of a list of the most influential writers of their time. Instead, a recent study has found, Jane Austen, author of “Pride and Prejudice, “ and Sir Walter Scott, the creator of “Ivanhoe,” had the greatest effect on other authors, in terms of writing style and themes.


These two were “the literary equivalent of Homo erectus, or, if you prefer, Adam and Eve,” Matthew L. Jockers wrote in research published last year. He based his conclusion on an analysis of 3,592 works published from 1780 to 1900. It was a lot of digging, and a computer did it.


The study, which involved statistical parsing and aggregation of thousands of novels, made other striking observations. For example, Austen’s works cluster tightly together in style and theme, while those of George Eliot (a k a Mary Ann Evans) range more broadly, and more closely resemble the patterns of male writers. Using similar criteria, Harriet Beecher Stowe was 20 years ahead of her time, said Mr. Jockers, whose research will soon be published in a book, “Macroanalysis: Digital Methods and Literary History” (University of Illinois Press).


These findings are hardly the last word. At this stage, this kind of digital analysis is mostly an intriguing sign that Big Data technology is steadily pushing beyond the Internet industry and scientific research into seemingly foreign fields like the social sciences and the humanities. The new tools of discovery provide a fresh look at culture, much as the microscope gave us a closer look at the subtleties of life and the telescope opened the way to faraway galaxies.


“Traditionally, literary history was done by studying a relative handful of texts,” says Mr. Jockers, an assistant professor of English and a researcher at the Center for Digital Research in the Humanities at the University of Nebraska. “What this technology does is let you see the big picture — the context in which a writer worked — on a scale we’ve never seen before.”


Mr. Jockers, 46, personifies the digital advance in the humanities. He received a Ph.D. in English literature from Southern Illinois University, but was also fascinated by computing and became a self-taught programmer. Before he moved to the University of Nebraska last year, he spent more than a decade at Stanford, where he was a founder of the Stanford Literary Lab, which is dedicated to the digital exploration of books.


Today, Mr. Jockers describes the tools of his trade in terms familiar to an Internet software engineer — algorithms that use machine learning and network analysis techniques. His mathematical models are tailored to identify word patterns and thematic elements in written text. The number and strength of links among novels determine influence, much the way Google ranks Web sites.


It is this ability to collect, measure and analyze data for meaningful insights that is the promise of Big Data technology. In the humanities and social sciences, the flood of new data comes from many sources including books scanned into digital form, Web sites, blog posts and social network communications.


Data-centric specialties are growing fast, giving rise to a new vocabulary. In political science, this quantitative analysis is called political methodology. In history, there is cliometrics, which applies econometrics to history. In literature, stylometry is the study of an author’s writing style, and these days it leans heavily on computing and statistical analysis. Culturomics is the umbrella term used to describe rigorous quantitative inquiries in the social sciences and humanities.


“Some call it computer science and some call it statistics, but the essence is that these algorithmic methods are increasingly part of every discipline now,” says Gary King, director of the Institute for Quantitative Social Science at Harvard.


Cultural data analysts often adapt biological analogies to describe their work. Mr. Jockers, for example, called his research presentation “Computing and Visualizing the 19th-Century Literary Genome.”


Such biological metaphors seem apt, because much of the research is a quantitative examination of words. Just as genes are the fundamental building blocks of biology, words are the raw material of ideas.


“What is critical and distinctive to human evolution is ideas, and how they evolve,” says Jean-Baptiste Michel, a postdoctoral fellow at Harvard.


Mr. Michel and another researcher, Erez Lieberman Aiden, led a project to mine the virtual book depository known as Google Books and to track the use of words over time, compare related words and even graph them.


Google cooperated and built the software for making graphs open to the public. The initial version of Google’s cultural exploration site began at the end of 2010, based on more than five million books, dating from 1500. By now, Google has scanned 20 million books, and the site is used 50 times a minute. For example, type in “women” in comparison to “men,” and you see that for centuries the number of references to men dwarfed those for women. The crossover came in 1985, with women ahead ever since.


In work published in Science magazine in 2011, Mr. Michel and the research team tapped the Google Books data to find how quickly the past fades from books. For instance, references to “1880,” which peaked in that year, fell to half by 1912, a lag of 32 years. By contrast, “1973” declined to half its peak by 1983, only 10 years later. “We are forgetting our past faster with each passing year,” the authors wrote.


JON KLEINBERG, a computer scientist at Cornell, and a group of researchers approached collective memory from a very different perspective.


This article has been revised to reflect the following correction:

Correction: January 27, 2013

An earlier version of this article misstated Matthew L. Jockers’s age. He is 46, not 48. 



Read More..

Brain Aging Linked to Sleep-Related Memory Decline


For decades scientists have known that the ability to remember newly learned information declines with age, but it was not clear why. A new study may provide part of the answer.


The report, posted online on Sunday by the journal Nature Neuroscience, suggests that structural brain changes occurring naturally over time interfere with sleep quality, which in turn blunts the ability to store memories for the long term.


Previous research had found that the prefrontal cortex, the brain region behind the forehead, tends to lose volume with age, and that part of this region helps sustain quality sleep, which is critical to consolidating new memories. But the new experiment, led by scientists at the University of California, Berkeley, is the first to link structural changes directly with sleep-related memory problems.


The findings suggest that one way to slow memory decline in aging adults is to improve sleep, specifically the so-called slow-wave phase, which constitutes about a quarter of a normal night’s slumber.


Doctors cannot reverse structural changes that occur with age any more than they can turn back time. But at least two groups are experimenting with electrical stimulation as a way to improve deep sleep in older people. By placing electrodes on the scalp, scientists can run a low current across the prefrontal area, essentially mimicking the shape of clean, high-quality slow waves.


The result: improved memory, at least in some studies. “There are also a number of other ways you can improve sleep, including exercise,” said Ken Paller, a professor of psychology and director of the cognitive neuroscience program at Northwestern, who was not involved in the research.


Dr. Paller said that a whole array of changes occurred across the brain during aging and that sleep was only one factor affecting memory function.


But Dr. Paller said that the study told “a convincing story, I think: that atrophy is related to slow-wave sleep, which we know is related to memory performance. So it’s a contributing factor.”


In the study, a research team in California took brain images from 19 people of retirement age and 18 in their early 20s. It found that a brain area called the medial prefrontal cortex, roughly behind the middle of the forehead, was about a third smaller on average in the older group than in the younger one — a difference due to natural atrophy over time, previous research suggests.


Before bedtime, the team had the two groups study a long list of words paired with nonsense syllables, like “action-siblis” and “arm-reconver.” The team used such nonwords because one type of memory that declines with age is for new, previously unseen information.


After training on the pairs for half an hour or so, the participants took a test on some of them. The young group outscored the older group by about 25 percent.


Then everyone went to bed — and bigger differences emerged. For one, the older group got only about a quarter of the amount of high-quality slow-wave sleep that the younger group did, as measured by the shape and consistency of electrical waves on an electroencephalogram machine, or EEG. It is thought that the brain moves memories from temporary to longer-term storage during this deep sleep.


On a second test, given in the morning, the younger group outscored the older group by about 55 percent. The estimated amount of atrophy in each person roughly predicted the difference between his or her morning and evening scores, the study found. Even seniors who were very sharp at night showed declines after sleeping.


“The analysis showed that the differences were due not to changes in capacity for memories, but to differences in sleep quality,” said Bryce A. Mander, a postdoctoral fellow at Berkeley, and the lead author of the study. His co-authors included researchers from the California Pacific Medical Center in San Francisco; the University of California, San Diego; and the Lawrence Berkeley National Laboratory.


The findings do not imply that medial prefrontal atrophy is the only age-related change causing memory problems, said Matthew P. Walker, a professor of psychology and neuroscience at Berkeley, and a co-author of the study.


“But these things are interrelated,” Dr. Walker said. “Essentially, with time, the less and less tissue you have in this prefrontal area, the less and less quality deep wave sleep you get, the less and less you remember of content that you just learned.”


Read More..