viernes, 21 de enero de 2011

To Really Learn, Quit Studying and Take a Test


To Really Learn, Quit Studying and Take a Test

Taking a test is not just a passive mechanism for assessing how much people know, according to new research. It actually helps people learn, and it works better than a number of other studying techniques.

The research, published online Thursday in the journal Science
, found that students who read a passage, then took a test asking them to recall what they had read, retained about 50 percent more of the information a week later than students who used two other methods.
One of those methods — repeatedly studying the material — is familiar to legions of students who cram before exams. The other — having students draw detailed diagrams documenting what they are learning — is prized by many teachers because it forces students to make connections among facts.
These other methods not only are popular, the researchers reported; they also seem to give students the illusion that they know material better than they do.
In the experiments, the students were asked to predict how much they would remember a week after using one of the methods to learn the material. Those who took the test after reading the passage predicted they would remember less than the other students predicted — but the results were just the opposite.
“I think that learning is all about retrieving, all about reconstructing our knowledge,” said the lead author, Jeffrey Karpicke, an assistant professor of psychology at Purdue University. “I think that we’re tapping into something fundamental about how the mind works when we talk about retrieval.”
Several cognitive scientists and education experts said the results were striking.
The students who took the recall tests may “recognize some gaps in their knowledge,” said Marcia Linn, an education professor at the University of California, Berkeley, “and they might revisit the ideas in the back of their mind or the front of their mind.”
When they are later asked what they have learned, she went on, they can more easily “retrieve it and organize the knowledge that they have in a way that makes sense to them.”
The researchers engaged 200 college students in two experiments, assigning them to read several paragraphs about a scientific subject — how the digestive system works, for example, or the different types of vertebrate muscle tissue.
In the first experiment, the students were divided into four groups. One did nothing more than read the text for five minutes. Another studied the passage in four consecutive five-minute sessions.
A third group engaged in “concept mapping,” in which, with the passage in front of them, they arranged information from the passage into a kind of diagram, writing details and ideas in hand-drawn bubbles and linking the bubbles in an organized way.
The final group took a “retrieval practice” test. Without the passage in front of them, they wrote what they remembered in a free-form essay for 10 minutes. Then they reread the passage and took another retrieval practice test.
A week later all four groups were given a short-answer test that assessed their ability to recall facts and draw logical conclusions based on the facts.
The second experiment focused only on concept mapping and retrieval practice testing, with each student doing an exercise using each method. In this initial phase, researchers reported, students who made diagrams while consulting the passage included more detail than students asked to recall what they had just read in an essay.
But when they were evaluated a week later, the students in the testing group did much better than the concept mappers. They even did better when they were evaluated not with a short-answer test but with a test requiring them to draw a concept map from memory.
Why retrieval testing helps is still unknown. Perhaps it is because by remembering information we are organizing it and creating cues and connections that our brains later recognize.
“When you’re retrieving something out of a computer’s memory, you don’t change anything — it’s simple playback,” said Robert Bjork, a psychologist at the University of California, Los Angeles, who was not involved with the study.
But “when we use our memories by retrieving things, we change our access” to that information, Dr. Bjork said. “What we recall becomes more recallable in the future. In a sense you are practicing what you are going to need to do later.”
It may also be that the struggle involved in recalling something helps reinforce it in our brains.
Maybe that is also why students who took retrieval practice tests were less confident about how they would perform a week later.
“The struggle helps you learn, but it makes you feel like you’re not learning,” said Nate Kornell, a psychologist at Williams College. “You feel like: ‘I don’t know it that well. This is hard and I’m having trouble coming up with this information.’ ”
By contrast, he said, when rereading texts and possibly even drawing diagrams, “you say: ‘Oh, this is easier. I read this already.’ ”
The Purdue study supports findings of a recent spate of research showing learning benefits from testing, including benefits when students get questions wrong. But by comparing testing with other methods, the study goes further.

“It really bumps it up a level of importance by contrasting it with concept mapping, which many educators think of as sort of the gold standard,” said Daniel Willingham, a psychology professor at the University of Virginia. Although “it’s not totally obvious that this is shovel-ready — put it in the classroom and it’s good to go — for educators this ought to be a big deal.”
Howard Gardner, an education professor at Harvard who advocates constructivism — the idea that children should discover their own approach to learning, emphasizing reasoning over memorization — said in an e-mail that the results “throw down the gauntlet to those progressive educators, myself included.”
“Educators who embrace seemingly more active approaches, like concept mapping,” he continued, “are challenged to devise outcome measures that can demonstrate the superiority of such constructivist approaches.”
Testing, of course, is a highly charged issue in education, drawing criticism that too much promotes rote learning, swallows valuable time for learning new things and causes excessive student anxiety.
“More testing isn’t necessarily better,” said Dr. Linn, who said her work with California school districts had found that asking students to explain what they did in a science experiment rather than having them simply conduct the hands-on experiment — a version of retrieval practice testing — was beneficial. “Some tests are just not learning opportunities. We need a different kind of testing than we currently have.”
Dr. Kornell said that “even though in the short term it may seem like a waste of time,” retrieval practice appears to “make things stick in a way that may not be used in the classroom.
“It’s going to last for the rest of their schooling, and potentially for the rest of their lives.”

The Greatest




The Greatest

HERE goes. This article completes my two-week project to select the top 10 classical music composers in history, not including those still with us. The argument, laid out in a series of articles, online videos and blog posts, was enlivened by the more than 1,500 informed, challenging, passionate and inspiring comments from readers of The New York Times. As often as I could, I answered direct questions online and jumped into the discussion.
Thomas Fuchs
The Greatest

The Top 10 Composers

Anthony Tommasini explores the qualities that make a classical composer great, maybe even the best of all time.

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Left, 1. Johann Sebastian Bach (1685-1750). From top left, 2. Ludwig van Beethoven (1770-1827), 3. Wolfgang Amadeus Mozart (1756 — 91). 4. Franz Peter Schubert (1797-1828). From middle left, 5. Claude Achille Debussy (1862 — 1918), 6. Igor Stravinsky (1882 — 1971), 7. Johannes Brahms (1833 — 97). From bottom left, 8. Giuseppe Verdi (1813 — 1901), 9. Richard Wagner (1813 — 83), 10. Bela Bartok (1881 — 1945).

Readers' Comments

I am about to reveal my list, though as those who have been with me on this quest already know, I’ve dropped hints along the way. And the winner, the all-time great, is ... Bach!
To step back for a moment, I began this project with bravado, partly as an intellectual game but also as a real attempt to clarify — for myself, as much as for anyone else — what exactly about the master composers makes them so astonishing. However preposterous the exercise may seem, when I found myself debating whether to push Brahms or Haydn off the list to make a place for Bartok or Monteverdi, it made me think hard about their achievements and greatness.
Ah, greatness. Early on I received a friendly challenge from a reader (“Scott”) who questioned the whole notion of greatness in music. He cited the title essay in “Listen to This,” a collection of astute, lively writings by Alex Ross, the music critic for The New Yorker and my good friend, which was published last year (Farrar, Straus & Giroux). In this essay he argues that the very term “classical music” makes this vibrant art form seem dead. Indeed, as he writes, “greatness” and “seriousness” are not classical music’s defining characteristics; it can also “be stupid, vulgar and insane.”
All true. Yet what came through in the comments from readers and, I hope, my articles and videos is that for most of us these composers are not monumental idols but living, compelling presences. Just as we organize our lives by keeping those we love in a network of support, we do something similar with the composers we rely on.
I was moved by how many readers could not wait to share their lists of favorite composers, whom, naturally, they also considered the greats. Even many of those who dismissed the exercise jumped right in: “This is absurd, of course. But here’s my list. And don’t you dare leave out Mahler.” OrBerg. Or Ligeti. Or, from one Baroque music enthusiast, Albinoni!
As a longtime champion of contemporary music, I was gratified to receive so many objections to my decision to eliminate living composers from consideration. Still, for me there was no other way. We are too close to living composers to have perspective. Besides, assessing greatness is the last thing on your mind when you are listening to an involving, exciting or baffling new piece.
So humbled by the discerning music lovers who wrote in, I now offer my own list. And remember: my editors gave the go-ahead for this project on condition that I go all the way and rank my 10 in order.
My top spot goes to Bach, for his matchless combination of masterly musical engineering (as one reader put it) and profound expressivity. Since writing about Bach in the first article of this series I have been thinking more about the perception that he was considered old-fashioned in his day. Haydn was 18 when Bach died, in 1750, and Classicism was stirring. Bach was surely aware of the new trends. Yet he reacted by digging deeper into his way of doing things. In his austerely beautiful “Art of Fugue,” left incomplete at his death, Bach reduced complex counterpoint to its bare essentials, not even indicating the instrument (or instruments) for which these works were composed.
On his own terms he could be plenty modern. Though Bach never wrote an opera, he demonstrated visceral flair for drama in his sacred choral works, as in the crowd scenes in the Passions where people cry out with chilling vehemence for Jesus to be crucified. In keyboard works like the Chromatic Fantasy and Fugue, Bach anticipated the rhapsodic Romantic fervor of Liszt, even Rachmaninoff. And as I tried to show in the first video for this project, through his chorales alone Bach explored the far reaches of tonal harmony.
The obvious candidates for the second and third slots are Mozart and Beethoven. If you were to compare just Mozart’s orchestral and instrumental music to Beethoven’s, that would be a pretty even match. But Mozart had a whole second career as a path-breaking opera composer. Such incredible range should give him the edge.
Still, I’m going with Beethoven for the second slot. Beethoven’s technique was not as facile as Mozart’s. He struggled to compose, and you can sometimes hear that struggle in the music. But however hard wrought, Beethoven’s works are so audacious and indestructible that they survive even poor performances.
I had an epiphany about Beethoven during the early 1980s when I heard the composer Leon Kirchner conduct the Harvard Chamber Orchestra. He began with a Piston symphony, a fresh, inventive Neo-Classical piece from the 1950s. “La Mer” by Debussy came next, and Kirchner, who had studied with Schoenberg and had a Germanic orientation, brought weighty, Wagnerian intensity to this landmark score, completed in 1905. The Debussy came across as more modern than the Piston.
After intermission Peter Serkin joined Kirchner for a performance of Beethoven’s Fourth Piano Concerto that brought out the mysticism, poetic reverie and wildness of the music. The Beethoven sounded like the most radical work in the program by far: unfathomable and amazing. I’m giving Beethoven the second slot, and Mozart No. 3.
Four? Schubert. You have to love the guy, who died at 31, ill, impoverished and neglected except by a circle of friends who were in awe of his genius. For his hundreds of songs alone — including the haunting cycle “Winterreise,” which will never release its tenacious hold on singers and audiences — Schubert is central to our concert life. The baritone Sanford Sylvan once told me that hearing the superb pianist Stephen Drury give searching accounts of the three late Schubert sonatas on a single program was one of the most transcendent musical experiences of his life. Schubert’s first few symphonies may be works in progress. But the “Unfinished” and especially the Ninth Symphony are astonishing. The Ninth paves the way for Bruckner and prefigures Mahler.




Debussy, who after hundreds of years of pulsating Germanic music proved that there could be tension in timelessness, is my No. 5. With his pioneering harmonic language, the sensual beauty of his sound and his uncanny, Freudian instincts for tapping the unconscious, Debussy was the bridge over which music passed into the tumultuous 20th century.

Readers' Comments

One who later walked that bridge was Stravinsky, my No. 6. During the years when “The Firebird” and “The Rite of Spring” were shaking up Paris, Stravinsky was swapping ideas with his friend Debussy, who was 20 years older. Yet Stravinsky was still around in the 1960s, writing serial works that set the field of contemporary music abuzz. One morning in 1971 I arrived at the door of the music building at Yale, on which someone had posted an index card with this simple news: “Igor Stravinsky died today.” It felt as if the floor had dropped out from under the musical world I inhabited. Stravinsky had been like a Beethoven among us.
I’m running out of slots. In some ways, as I wrote to one reader, either a list of 5 or a list of 20 would have been much easier. By keeping it to 10, you are forced to look for reasons to push out, say, Handel or Shostakovich to make a place for someone else.
Some musicians I respect have no trouble finding shortcomings in Brahms. He did sometimes become entangled in an attempt to extend the Classical heritage while simultaneously taking progressive strides into new territory. But at his best (the symphonies, the piano concertos, the violin concerto, the chamber works with piano, the solo piano pieces, especially the late intermezzos and capriccios that point the way to Schoenberg) Brahms has the thrilling grandeur and strangeness of Beethoven. Brahms is my No. 7.
In an earlier installment of this series I tried to weasel out of picking Romantic composers other than Brahms by arguing that the era fostered originality and personal expression above all. To a genius like Chopin, having a distinctive voice and giving vent to his inspirations were more important than achieving some level of quantifiable greatness.
But the dynamic duo of 19th-century opera, Verdi and Wagner, aimed high. As I already let slip, they both make my list. That a new production of a Verdi opera, like Willy Decker’s spare, boldlyreimagined staging of “La Traviata” at the Metropolitan Opera, can provoke such heated passions among audiences is testimony to the enduring richness of Verdi’s works. A production of Wagner’s “Ring” cycle has become the entry card for any opera company that wants to be considered big time. The last 20 minutes of “Die Walküre” may be the most sadly beautiful music ever written.
But who ranks higher? They may be tied as composers but not as people. Though Verdi had an ornery side, he was a decent man, an Italian patriot and the founder of a retirement home for musicians still in operation in Milan. Wagner was an anti-Semitic, egomaniacal jerk who transcended himself in his art. So Verdi is No. 8 and Wagner No. 9.
One slot left. May Haydn forgive me, but one of the Vienna Four just had to go, and Haydn’s great legacy was carried out by his friend Mozart, his student Beethoven and the entire Classical movement. My apologies to Mahler devotees, so impressively committed to this visionary composer. Would that I could include my beloved Puccini.
I was heartened by the hundreds of readers who championed 20th-century composers like Ligeti, Messiaen, Shostakovich, Ives, Schoenberg, Prokofiev and Copland, all of whom are central to my musical life. Then there is Berg, who wrote arguably the two greatest operas of the 20th century. His Violin Concerto, as I explained in my first video, would make my list of top 10 pieces. I was disappointed that an insignificant number of readers made a case for Britten. I have some advocacy work to do.
I received the most forceful challenges from readers who thought that pre-Bach composers simply had to be included, especially Monteverdi. Though Monteverdi did not invent opera, he took one look at what was going in Florence around 1600 and figured out how this opera thing should really be done. In 1607 he wrote “Orfeo,” the first great opera. His books of madrigals brought the art of combining words and music to new heights. The Monteverdi contingent is probably right.
But forced to pick only one more composer, I’m going with Bartok. In an earlier piece I made my case for Bartok, as an ethnomusicologist whose work has empowered generations of subsequent composers to incorporate folk music and classical traditions from whatever culture into their works, and as a formidable modernist who in the face of Schoenberg’s breathtaking formulations showed another way, forging a language that was an amalgam of tonality, unorthodox scales and atonal wanderings.
So that’s my list.
And now, in an act of contrition, I am beginning a personal project to listen nonstop to recordings of Britten, Haydn, Chopin, Monteverdi, Ligeti and those composers whom I could not squeeze in but whose music carries me through my days.

Efectos circadianos sobre el bloqueo subaracnoideo con bupivacaína hiperbárica


Efectos circadianos sobre el bloqueo subaracnoideo con bupivacaína hiperbárica
Circadian Effects on Neural Blockade of Intrathecal Hyperbaric Bupivacaine
Cheol Lee, Deok Hwa Choi, and Soo Uk Chae.
Departments of Anesthesiology and Pain Medicine, Orthopaedic Surgery, Wonkwang University School of Medicine, Iksan, Korea
Korean J Pain 2010; 23: 186-189. 
Background: Circadian variations in the absorption, distribution, protein binding, elimination and metabolism of drugs account for many of the administration-time-dependent differences in their pharmacokinetics. The aim of this study is to determine whether the time of intrathecal injection influences spinal anesthesia. Methods: Ninety patients scheduled for orthopedic surgery were randomly assigned to three groups. Each group received spinal anesthesia with 0.5% bupivacaine 10 mg at different times; group AM (8 am to 12:00), group Noon (12:00 to 4:00 pm) and group PM (4:00 pm to 8:00 pm). Sensory and motor blockade were assessed by pinprick and a four-point modified Bromage scale. Time to first postoperative analgesic requirement and side effects such as hypotension, bradycardia, nausea, and shivering were recorded. Results: No significant differences were found among the three groups in peak sensory blockade, duration of motor block to Bromage 1 or side effects, but time to first postoperative analgesic requirement (P = 0.008), and recovery time of S1 sensation to pinprick were significantly prolonged in group Noon compared with the other groups (P = 0.03). Conclusions: The time of administration of spinal local anesthetics influences the duration of local anesthesia.

Enlace para leer el articulo completo en PDF


Atentamente
Anestesiología y Medicina del Dolor

Remifentanil en pacientes cardiacos graves y Comparación de la efectividad de lidocaína y salbutamol sobre la tos provocada por remifentanil intravenoso durante la inducción de la anestesia


Remifentanil en pacientes cardiacos graves
Remifentanil in critically ill cardiac patients
Laura Ruggeri, Giovanni Landoni, Fabio Guarracino, Sabino Scolletta, Elena Bignami, Alberto Zangrillo
Department of Anesthesia and Intensive Care Medicine, Università Vita-Salute San Raffaele, Milan, Italy.  Department of Cardiothoracic, Cardiothoracic Anesthesia and Intensive Care Medicine, University Hospital of Pisa, Pisa, Italy.  Department of Surgery and Bioengineering, Unit of Cardiothoracic Anesthesia and Intensive Care, University of Siena, Siena, Italy
Ann of Cardiac Anaesth 2011;14: 6-12.     DOI: 10.4103/0971-9784.74393

Remifentanil has a unique pharmacokinetic profile, with a rapid onset and offset of action and a plasmatic metabolism. Its use can be recommended even in patients with renal impairment, hepatic dysfunction or poor cardiovascular function. A potential protective cardiac preconditioning effect has been suggested. Drug-related adverse effects seem to be comparable with other opioids. In cardiac surgery, many randomized controlled trials demonstrated that the potential benefits of the use of remifentanil not only include a profound protection against intraoperative stressful stimuli, but also rapid postoperative recovery, early weaning from mechanical ventilation, and extubation. Remifentanil shows ideal properties of sedative agents being often employed for minimally invasive cardiologic techniques, such as transcatheter aortic valve implantation and radio frequency treatment of atrial flutter, or diagnostic procedures such as transesophageal echocardiography. In intensive care units remifentanil is associated with a reduction in the time to tracheal extubation after cessation of the continuous infusion; other advantages could be more evident in patients with organ dysfunction. Effective and safe analgesia can be provided in case of short and painful procedures (i.e. chest drain removal). In conclusion, thanks to its peculiar properties, remifentanil will probably play a major role in critically ill cardiac patients. 

Comparación de la efectividad de lidocaína y salbutamol sobre la tos provocada por remifentanil intravenoso durante la inducción de la anestesia
Comparison of the effectiveness of lidocaine and salbutamol on coughing provoked by intravenous remifentanil during anesthesia induction.
Bang SR, Ahn HJ, Kim HJ, Kim GH, Kim JA, Yang M, Kim JK, Cho HS.
Department of Anesthesiology and Pain Medicine, Haeundae Paik Hospital, Inje University School of Medicine, Busan, Korea.
Korean J Anesthesiol. 2010 Nov;59(5):319-22. Epub 2010 Nov 25. 

Abstract
BACKGROUND: Coughing is a side effect of opioids that is rarely studied. Here, we evaluated the incidence of remifentanil induced coughing during anesthesia induction in an attempt to identify its risk factors and to examine the preventive effects of lidocaine and salbutamol.
METHODS: A total of 237 patients scheduled to undergo general anesthesia were allocated randomly into three groups. Group C received no medication, while Group L received 2% lidocaine at 0.5 mg/kg intravenously 1 minute prior to remifentanil infusion and Group S inhaled one metered aerosol puff of salbutamol 15 minutes prior to entering the operating room. Remifentanil was infused at 5 ng/ml by target controlled infusion and coughing was measured for five minutes and graded as none, mild, moderate, or severe based on the number of coughs. RESULTS: The incidences of coughing were 30.4%, 25.3%, and 35.4% in Groups C, L, and S, respectively. The incidences, onset times, and severity of coughing did not differ significantly among groups. In addition, multivariate analysis showed that non-smoking and a lower body weight were risk factors of remifentanil-induced coughing (odds ratio, 8.13; P = 0.024, 1.11, and 0.004, respectively). CONCLUSIONS: The incidence of remifentanil-induced coughing was 30%. A total of 0.5 mg/kg lidocaine and 1 metered aerosol puff of salbutamol did not prevent coughing. Non-smoking and low body weight were found to be risk factors of remifentanil-induced coughing

Atentamente
Anestesiología y Medicina del Dolor