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Learn Music While You Sleep

Hearing a song during the night might improve your playing


If you have been practicing a piece of music, hearing it again while you are sleeping could help you play it more accurately the next time, according to a study from Northwestern University published online in June in Nature Neuroscience.

Sixteen participants with a range of musical education learned to play two melodies by pressing keys in time with a sequence of moving circles, as in the video game Guitar Hero. During a 90-minute nap, one of the tunes was played over and over during slow-wave sleep, which is thought to be an important period for memory consolidation. When the participants awoke, they were better at both tunes, but their accuracy was especially improved for the tune they had heard (without knowing it) in their sleep.

“Memory processing during sleep happens, and it can be beneficial,” says senior author Ken A. Paller. “The findings we have suggest that slow-wave sleep is a very important part of the process.” Future research will focus on the memory mechanisms at work during this stage of the sleep cycle—and their practical implications.

Tomado de: http://www.scientificamerican.com/article.cfm?id=learn-music-while-you-sleep&WT.mc_id=SA_CAT_MB_20121205

¿Cuánto ejercicio hay que practicar para tener buena memoria?

El ejercicio breve e intenso mejora la memoria. Así lo han demostrado investigadores del Centro de Neurobiología del Aprendizaje y la Memoria de la Universidad de California. Sus conclusiones se publican en el último número de la revista Journal of Alzheimer's Disease.

Los neurobiólogos realizaron un experimento para tratar de descubrir qué efecto surtía pedalear sobre una bicicleta estática durante 6 minutos al 70% de la capacidad máxima después de visualizar una serie de fotografías de naturaleza y animales. Cuando una hora después a los sujetos se les sometió por sorpresa a un test de memoria sobre las imágenes que habían visto previamente, los resultados mostraron claramente que quienes habían hecho ejercicio físico tenían mejor memoria que quienes no habían hecho deporte. Los sujetos participantes tenían edades comprendidas entre 50 y 85 años. Sabrina Segal y sus colegas californianos lo atribuyen a que mientras practicamos un ejercicio físico intenso se libera norepinefrina, un mensajero químico del cerebro que juega un papel importante en la modulación del aprendizaje y la memoria.

“Con una población cada vez más envejecida, necesitamos averiguar cómo mejorar la calidad de vida y prevenir el deterioro mental”, afirma Segal, que confía en que el ejercicio sea una de las respuestas.

Tomado de: http://www.muyinteresante.es/icuanto-ejercicio-hay-que-practicar-para-tener-buena-memoria

Fumar deteriora la memoria, el aprendizaje y el razonamiento

Una investigación realizada en el Reino Unido profundiza sobre los perjuicios del tabaco

Fumar deteriora las funciones de memoria, aprendizaje y razonamiento del cerebro, tal y como evidencia una investigación del King College de Londres (Reino Unido) que publica la revista especializada 'Age and Ageing', y que recoge la BBC.

En concreto, los expertos de este centro británico afirman que el hábito tabáquico "pudre" este órgano del ser humano. Por ello, consideran que la gente "necesita ser consciente de que los estilos de vida pueden dañar la mente y el cuerpo".

No obstante, los científicos del King College han llegado a estas conclusiones a partir de otra investigación que estudiaba los vínculos entre la probabilidad de un ataque al corazón o un derrame cerebral y el estado del cerebro. En éste, en el que han participado 8.800 personas de más de 50 años, se ha descubierto que la presión arterial alta y el sobrepeso también parecían afectar al cerebro, "pero en menor medida", afirman.

Las pruebas realizadas sobre estos pacientes fueron efectuadas también a los cuatro y a los ocho años de comenzar el estudio. Los resultados de las mismas demuestran que el riesgo general de ataque cardiaco o accidente cerebrovascular está "significativamente asociado con el deterioro cognitivo", por lo que también deducen que hay "una asociación consistente entre fumar y las puntuaciones más bajas en las pruebas".

Dejar de fumar podría evitar enfermedades como la demencia

Para uno de los investigadores del King College, el doctor Alex Dregan, a pesar de que el deterioro cognitivo "se vuelve más común con la edad, se han identificado una serie de factores de riesgo que pueden estar asociados con el deterioro cognitivo acelerado, todo lo cual, "podría ser modificable". Con ello, podrían evitarse enfermedades "como la demencia", asegura.

En este sentido, el miembro de Alzheimer's Research UK, el doctor Simon Ridley, manifiesta que la investigación "ha vinculado repetidamente tabaquismo e hipertensión arterial con un mayor riesgo de deterioro cognitivo y demencia". Por ello, apuesta por "cuidar la salud cardiovascular a partir de la mediana edad".

Por último, desde la Sociedad de Alzheimer alerta, además de que "una de cada tres personas mayores de 65 años desarrollará demencia" en el futuro, de que fumar "también es malo para el corazón". En contrapartida recomienda "una dieta equilibrada, mantener un peso saludable y hacer ejercicio regularmente".

Tomado de: http://www.farodevigo.es/vida-y-estilo/salud/2012/11/27/fumar-deteriora-memoria-aprendizaje-razonamiento/718228.html

How Long Will a Lie Last? New Study Finds That False Memories Linger for Years

True memories fade and false ones appear.

Each time we recall something, the memory is imperfectly re-stitched by our brains. Our memories retain familiarity but, like our childhood blankets, can be recognizable yet filled with holes and worn down with time.

To date, research has shown that it is fairly easy to take advantage of our fallible memory. Elizabeth Loftus, cognitive psychologist and expert on human memory, has found that simply changing one word in a question can contort what we recall. In one experiment, Loftus had participants watch a film of a car crash, and then asked about what they saw. They were either asked “How fast were the cars going when they hit each other,” or “How fast were the cars going when they smashed into each other.” One week later the participants returned for some memory questions. Loftus asked whether or not there was broken glass at the scene of the accident. Those participants that heard the word “smashed” were more than twice as likely to recall seeing broken glass than those who heard the word “hit.” Keep in mind, there was in fact no broken glass at the scene[2].

This kind of insight—that our memories are terrible camcorders of reality—had serious pop culture ramifications. “Repression” and “repressed memories” have entered our culture’s lexicon, without evidential support. Even with numerous accusations of sexual abuse and other childhood horrors filed in court with the explosion of “recovered memory therapy,” the same research pioneered by experts like Loftus has suggested that most if not all of these “repressed” memories are merely false ones[1]. At CSICon, a skeptic’s conference earlier this year in Nashville, Tennessee, Loftus herself noted that the same techniques used to implant false memories in psychological experiments are precisely the techniques used by repression therapists to recover supposedly buried traumas.

Nearly four decades later, Loftus and colleagues aim to further memory science once again. Introducing a false memory in experiment can be done quickly and with some degree of reliability, but how long does the lie last? Surely bolstered by a digital age reverberating with misinformation, the results point to a disturbingly long half-life of lies.

Memory Fades

Earlier this year, Zhu et al.[3] tested the veracity of a quickly incepted false memory. After selecting 342 participants, the research team set about twisting their memory with two events, shown on slides, crafted to encourage endorsement of a falsehood. The researchers showed participants 50 slides of each event in quick succession, one depicting a man breaking into a car and stealing things from it, and the other depicting a girl’s wallet being stolen by a seemingly nice man.

To create a false memory, the researchers followed this slideshow with a narration of the events that took place, mimicking “eyewitness” accounts. 50 sentences were presented to participants that supposedly accurately described each slide seen in the events. However, 12 “key” slides were manipulated in the narration sentences. For example, if participants saw the thief put the woman’s wallet in his jacket pocket, the narration would describe the thief putting the wallet in his pants pocket. Other participants would see different combinations of these memory manipulations.

From Zhu, et al., 2012, pg. 303

The research team then tested for the implantation of false memories by giving participants both a recognition test (what did you see in the pictures?) and a source-monitoring test (did you choose that answer because you read it, saw it, both, or guessed?).

Importantly, the researchers made sure that false memories could be separated from simply wrong ones. For example, the slides would show a man stealing a woman’s wallet and then hiding behind a tree, while the narration would describe him hiding behind a door after the petty theft. When asked, “where was the man hiding?” in the recognition test, participants could answer either “behind a tree” (true memory), “behind a door” (false memory), or “behind a car” (wrong/“foil” memory). In this way, Zhu et al. could determine if their false memories incepted by the narrations stuck in the participants’ minds.

A year and a half later the same event slides were presented to the original participants. But this time during the slideshow, the experimenters paused it and asked participants what would happen next, right before the “key” slides from the original test. What was remembered from the testing 1.5 years prior would the participants’ only way to advance the slideshow.

Disturbingly, as the researchers note, “the false memory briefly introduced in an experimental setting seemed to have similar strength…as true memory” (pg. 306).

In the first test, participants endorsed 61% of the true items and 31% of the misinformation items as what really happened in the 12 manipulated slides. A year and a half later, only 45% of the true items were endorsed, showing a decent memory. But this time, 39% of the misinformation items were taken as true, a statistically significant increase.

We seem to think that misinformation is somehow “weaker” than the truth, that it does not last as long or pierce as deep. The research disagrees. Misinformation can be just as enduring, and even increase in strength over time. This has real world consequences. Consider how critically we must view eyewitness testimony (even more so than usual) when there is conflicting video and verbal accounts. Maybe a policeman has a witness watch a burglary caught on tape, pausing the video to ask what happens next. Distinguishing between a true and a false memory based on strength of recall then seems a futile exercise.

True memories fade, and lies darken.

Viral Falsities

Sharing is now one of the easiest things to do, given a decent bandwidth. And rumors spread like wildfire. Numerous celebrities have been declared dead by social media and reported in the mainstream (Jeff Goldblum, Bill Nye, Morgan Freeman, etc.). A group of bloggers nearly “screwed” the entire Apple community with a simple lie, and documented just how expansive it became.

Most recently, the landfall of hurricane Sandy generated a steady stream of lies in the form of doctored pictures. Unnatural clouds loomed over New York, the Statue of Liberty was engulfed by a monstrous “Day After Tomorrow” wave, and sharks patrolled the streets of New Jersey. Though sources like The Atlantic provided real-time debunking of many of these images, I suspect that the fake photos made much more of a dent than their corrections.

So in a deluge of Sandy tweets and links and articles we witnessed a slightly flipped version of the memory study discussed above. Fake images were presented, corrected shortly after by narrations (and further pictures) from news websites and knowledgeable tweeters. The discrepancy between what was seen (“A shark on a New Jersey lawn!”) and what was read (“That shark photo was a fake!”) made for a perfect experiment in implanting false memories.

The data on this disconnect would need to be collected and crunched, but based on memory science we know what to expect. Years from now, when we think back on hurricane Sandy and the destruction it caused, we are eventually bound to hear:

“Remember when sharks were swimming the streets of New Jersey?”

Tomado de: http://blogs.scientificamerican.com/guest-blog/2012/11/14/how-long-will-a-lie-last-new-study-finds-that-false-memories-linger-for-years/?WT_mc_id=SA_WR_20121121

Coeficiente intelectual humano retrocede, perdemos imaginación y memoria

Contradiciendo la tendencia universal que afirma una evolución intelectual de los humanos a lo largo de la prehistoria y la modernidad, científicos de la Universidad de Stanford, despliegan la teoría en contrario: el coeficiente intelectual de la humanidad disminuye en forma lenta pero concreta.

El informe publicado en Trends and Genetic, refiere a la hipótesis desarrollada por el equipo que encabeza el biólogo Gerald Crabtree, donde se establece que el relacionamiento entre el ser humano y la agricultura ha sido determinante para ello.

El estudio contradice al “efecto Flynn”, la más tradicional de las teorías sobre el particular, creada por el investigador James Robert Flynn, quien centró sus certezas en la evolución del coeficiente intelectual generación tras generación desde comienzos del siglo XX.

La supervivencia individual y la colectiva

Según el nuevo estudio todo cambió en función del relacionamiento del hombre con su base de sustento. Mientras hace miles de años, los hombres vivían en un medio salvaje en pequeños grupos, cada habilidad intelectual era absolutamente clave para sobrevivir. Sin emplear el cerebro constantemente, el hombre primitivo no podía ni alimentarse ni protegerse del entorno hostil: solamente los más inteligentes sobrevivían. Esta presión hizo que la inteligencia aumentara de forma constante durante muchas centurias.

Con el advenimiento de la agricultura, los hombres pasaron a vivir en grupos más grandes y en el mismo lugar, con lo que los más débiles empezaron a ser protegidos. Al vivir en comunidades mayores la inteligencia individual deja de ser absolutamente vital. Los estudiosos afirman que ello continuó en esa suerte involutoria constantemente, tal así que un ciudadano de la antigua Grecia que viaja en el tiempo, sería hoy más inteligente que el promedio en tanto tendría mucha más imaginación y más memoria.

Según el biólogo, la inteligencia depende de entre 2.000 y 5.000 genes que son particularmente susceptibles de sufrir mutaciones en cortos períodos de tiempo.

Tomado de: http://www.lr21.com.uy/tecnologia/1075240-coeficiente-intelectual-humano-esta-retrocediendo-perdemos-imaginacion-y-memoria

Artículos:


Gerald R. Crabtree. Our fragil intelect. Part I. Trends in genetics,  Available online 12 November 2012
Gerald R. Crabtree. Our fragil intelect. Part II. Trends in genetics,  Available online 12 November 2012

Memory in Old Age Can Be Bolstered

When Mick Jagger first sang “What a drag it is getting old,” he was 23 years old. Now at 69, he is still a veritable Jumpin' Jack Flash on stage. Jagger seems to have found the secret to staying physically fit in his advancing years, but getting old can be a drag on the psyche. Many older adults fear memory loss and worry they are headed down the road to dementia, such as Alzheimer's disease. Every time they forget their keys, leave a door unlocked or fail to remember a name, they are reminded of this nagging concern. In most cases, however, such annoying incidents are part of normal age-related memory loss, not a sign of impending dementia.

Although lots of older adults think such a decline is inevitable, there is good news for many of them. Researchers have developed an array of helpful methods and activities that exercise our minds and bodies that can help keep the older mind in relatively good condition. In this column, we examine the most promising ways to shore up memory in the normal aging brain.

Memory Divided

Memory is not a single entity. The term encompasses several types of remembering, not all of which decline with age. For instance, older people still retain their vocabulary, along with general knowledge about the world (semantic memory). They can also perform certain routine tasks, such as making an omelet or typing on a computer (procedural memory), about as well as they could when they were younger. People do become worse, however, at recalling recent events in their lives (episodic memory) or where they first learned a piece of information (source memory), managing the temporary storage of short-term information (working memory), and remembering to do things in the future (prospective memory).

Prospective memory, in particular, is an important target for memory strategies because forgetting upcoming tasks or appointments can cause considerable frustration or embarrassment. In 2002 psychologist Narinder Kapur of Southampton General Hospital in England and his colleagues reviewed studies on the effectiveness of various common techniques to bolster prospective memory. They found that external aids such as making lists or programming reminders into a cellphone could be helpful in reducing memory problems such as failing to pay bills or attend meetings.

Another successful strategy involves associating information to be recalled with an image, sentence, phrase or word. The more personally relevant the association is, the more likely it is to be remembered, an approach known as self-referential processing. For example, if we need to return a book to the library, we might imagine ourselves doing just that. Made-up acronyms also can be a big help. In this strategy, a person forms a new word from the initial letters of what he or she wants to remember. To remember to buy a birthday gift for his wife, for example, a man might construct the acronym “BIG” for “Buy Gift.”

In 2008 psychologists Betty L. Glisky of the University of Arizona and Martha L. Glisky of the Evergreen Hospital Medical Center described other useful methods for improving memory that involve visual or semantic elaboration. In one of these, a person conjures up images related to something he or she wants to retain. To remember the name “Peggy,” you might imagine a pirate with a wooden (peg) leg. Such a tactic could be helpful as long as you do not end up calling her “Pegleggy.”

A semantic approach entails tacking on words to what you wish to recall. For example, in a music appreciation class that one of us (Arkowitz) took in elementary school, the teacher asked the class to associate the main musical theme of the classical piece, the Peer Gynt Suite, with the following rather silly sentence: “Morning is dawning and Peer Gynt is yawning and music is written by Grieg.” The tie-in with the phrase was designed to help the kids remember the name of the composer.

Although Glisky and Glisky found support for these visual and semantic techniques, among others, they cautioned that memory improvements in the laboratory do not necessarily translate to enhancements in daily life, because these benefits depend on people practicing and using the tactics regularly. This gap in efficacy may be widest for strategies that take considerable time and effort to learn. Also, improvements in one area of memory often do not generalize to others.

Studies have found some support for the validity of the saying “Use it or lose it.” The more we use our memory—for example, reading, doing crossword puzzles and playing board games—the better it may be, probably because such activities involve considerable use of memory. Of course, those with better memories may also be more likely to exercise their minds in the first place, accounting for some (but probably not all) of the association between good memory and amount of cognitive stimulation.

Fit Body, Fit Mind

If Jagger is as physically fit as he looks, his mind may be following suit. Some studies have found that higher levels of aerobic exercise are associated with better memory in older adults. Although many of these studies do not prove that aerobic exercise causes the memory improvements, some do suggest a causal connection. When psychologist Stanley Colcombe of the University of Illinois at Urbana-Champaign and his colleagues reviewed 18 controlled studies addressing this association in 2003, they found evidence that aerobic exercise did indeed lead to enhancements in memory.

Sustained aerobic activity may not be the only way to keep your mind agile and your memory sharp. In a study published in 2011 neurologist Ruth Ruscheweyh of the University of Münster in Germany and her colleagues assessed total physical activity in 62 older adults over six months. Their questionnaire included both formal exercise and daily routines such as walking to work, climbing stairs and gardening. The researchers linked reported increases in overall activity, no matter its type, with improvements in episodic memory at the end of six months. The greater the rise in activity levels, the bigger the memory boost. Thus, keeping physically active through regular workouts along with everyday errands and tasks may be the best recipe for reinvigorating your powers of recollection. [For more on the connection between physical and mental fitness in old age, see “Fit Body, Fit Mind?” by Christopher Hertzog, Arthur F. Kramer, Robert S. Wilson and Ulman Lindenberger; Scientific American Mind, July/August 2009.]
The research suggests that many memory techniques as well as a physically and mentally energetic lifestyle can improve memory in older adults. We still have a long way to go before we have highly effective methods, but given the vigor of this field, we can expect great progress in the near future.

Tomado de:  http://www.scientificamerican.com/article.cfm?id=memory-in-old-age-can-be-bolstered&page=2

El cerebro, ¿cómo memorizamos y aprendemos?

¿Cómo decide nuestro cerebro?

¿Decidimos antes de procesar suficientes datos del mundo exterior? Un estudio realizado por investigadores de la Universidad Autónoma de Madrid (UAM) y la Universidad Nacional Autónoma de México sostiene que, a la hora de tomar decisiones en contextos de mucha incertidumbre, lo que escogemos no sólo se fundamenta en evidencias sensoriales, sino también en mecanismos internos y complejos del cerebro. 

En un trabajo publicado en el último número de la revista PNAS (Proceedings of the National Academy of Sciences), neurocientíficos españoles y mexicanos aportan pruebas que contradicen la teoría comúnmente aceptada hasta ahora para explicar la actividad que ocurre en nuestro cerebro cuando tomamos decisiones basadas en la percepción. Según esta teoría vigente, la llegada de un estímulo sensorial aumenta la actividad neuronal y la decisión se alcanza cuando esta actividad supera cierto umbral.

Para refutar esta idea, en una serie experimentos los investigadores emplearon como estimulación sensorial una vibración táctil que era aplicada en uno de los dedos de los sujetos estudiados, sin que estos supieran en qué momento se produciría el estímulo. Además, la vibración a veces era extremadamente débil o incluso ausente.
Los voluntarios debían indicar si habían percibido o no una vibración, y se les recompensaba en los casos en que sus decisiones eran correctas. Los resultados obtenidos mostraron que existe una señal generada internamente que impulsa al individuo a afirmar categóricamente que ha percibido una vibración incluso cuando no ha sido aplicada. 

Según los autores, la conclusión de los resultados es que las decisiones tomadas en contextos de mucha incertidumbre están, en muchos casos, definidas por mecanismos cerebrales independientes de la observación. Y que la respuesta es el resultado de deducciones o inferencias que realiza el cerebro sobre lo que ocurre en el mundo sensorial, a veces antes de que suceda nada.

Tomado de: http://www.muyinteresante.com.mx/ciencia/522254/toma-decisiones-interna-del-cerebro-decide/

Borges and Memory: Encounters with the Human Brain [Excerpt]

What is the genesis of Funes the Memorious, the Jorge Luis Borges story about a mnemonist that fascinates neuroscientists, and is as famed a fictional treatise on memory as anything but Proust’s Remembrance of Things Past?

By Rodrigo Quian Quiroga

UNES AND OTHER CASES OF EXTRAORDINARY MEMORY

 

June 7, 1942, was a Sunday like any other amid the altered routine of the Second World War. The front page of the newspaper La Nación¹ reported on the British onslaught, which continued with a bombing campaign over the German industrial area in the Ruhr. On the same page one could read about the casualties inflicted on the Japanese fleet at Midway and about British infantry tanks’ attacking German positions in the desert. Pages 5 and 6 of the paper, in between advertisements for Eno’s “Fruit Salt” (a digestive aid selling at $0.70 per vial) and Fernet Branca (a beverage that should be brought home as one brings a friend), give an account of an earthquake without victims in Mendoza and announce that tire factories can start restoring used tires. In sports, Argentinos Juniors beat Sportivo Alsina by 4 goals to 1 in their campaign to reach the premier league, and the entertainment pages promote Pirates of the Caribbean, in Technicolor, and a new movie starring Olivia de Havilland and Henry Fonda at $1.50 a superpullman seat. June 7, 1942, a day like any other according to La Nación, except for a short story appearing in the Arts and Letters section that would turn this issue of the newspaper into a historic document. The first page of this Sunday supplement features a story by Stefan Zweig; the second page contains an essay by Ernesto Sabato praising Galileo; and on the third page, almost hidden in plain sight, for the first time appears “Funes the Memorious,” Jorge Luis Borges’s monumental short story, with an illustration by Alejandro Sirio.

“Funes the Memorious” tells the vicissitudes of Ireneo Funes, a peasant from Fray Bentos, who after falling off a horse and hitting his head hard recovers consciousness with the incredible skill—or perhaps curse—of remembering absolutely everything.

Says Borges of Funes:

Nosotros, de un vistazo, percibimos tres copas en una mesa; Funes, todos los vástagos y racimos y frutos que comprende una parra. Sabía las formas de las nubes australes del amanecer del 30 de abril de 1882 y podía com- pararlas en el recuerdo con las vetas de un libro en pasta española que sólo había mirado una vez y con las líneas de la espuma que un remo levantó en el Río Negro la víspera de la acción del Quebracho.²

Page 3 of the Arts and Letters section of La Nación of June 7, 1942, where "Funes the Memorious" was first published.

[We, at a stroke, perceive three cups lying on a table; Funes would see all the shoots and clusters and fruit comprised by a vine. He knew the shapes of the southern clouds at dawn on April 30, 1882, and could compare them in his memory with the streaks on a book of Spanish cover that he had seen only once and with the swirls on the foam raised by an oar in the Río Negro on the eve of the battle of the Quebracho.]
Jorge Luis Borges (1899–1986) has received universal acclaim for the depth with which he approached matters of philosophic and scientific import in his writings. In Borges’s hands, the topic of infinity comes alive either as a point that contains the universe (“The Aleph”), impregnable labyrinths (“The Two Kings and the Two Labyrinths”), a library that is eternally repeated (“The Library of Babel”), stories that subdivide into innumerable possibilities (“The Garden of Forking Paths”), or an imperial map so perfectly detailed that it ends up having the size of the empire itself (“Of Rigor in Science”). In “Funes the Memorious,” a story of barely 12 pages that was eventually published as part of Ficciones (1944), Borges again plays with the infinite in a context no less fascinating: the vast labyrinths of memory and the consequences of having an unlimited capacity to remember.

Funes is first mentioned in an obituary of James Joyce, “A Fragment on Joyce,” published in 1941 in the magazine Sur.³ There, with some measure of sarcasm, Borges says that to read straight through a “monster” like Joyce’s Ulysses—a 400,000-word reconstruction of a single day in Dublin—requires another monster able to remember an infinite number of details. The strange thing about the obituary is that Borges barely refers to Joyce or his work and instead describes Ireneo Funes, the main character of the story he was writing at the time.
Entre las obras que no he escrito ni escribiré (pero que de alguna manera me justifican, siquiera misteriosa y rudimental) hay un relato de unas ocho o diez páginas cuyo profuso borrador se titula “Funes el memorioso”.
. . . Del compadrito mágico de mi cuento cabe afirmar que es un precursor de los superhombres, un Zaratustra suburbano y parcial; lo indiscutible es que es un monstruo. Lo he recordado porque la consecutiva y recta lectura de las cuatrocientas mil palabras de Ulises exigiría monstruos análogos.⁴
[Among the works that I have not written and will never write (but that somehow justify me, in however mysterious and rudimentary a way) there is a short story, some eight to ten pages long, whose copious draft is entitled “Funes the Memorious.” . . . Of the magical compadrito of my story I can state that he is a precursor to supermen, a suburban, incomplete Zarathustra; what cannot be denied is that he is a monster. I have remembered him because a straight, uninterrupted reading of Ulysses’s four hundred thou- sand words would require similar monsters.]

Title page of the first volume of a 1669 edition of Pliny’s Naturalis historia.

In the preface to “Artifices,” the second part of Ficciones, Borges argues that “Funes the Memorious” is a long metaphor of insomnia. In fact, toward the end of the story he mentions that Funes found sleeping difficult, because to sleep is to get distracted from the world. Borges gives more details on the way he conceived Funes during his own sleepless nights (perhaps during a sticky summer night at the quinta in Adrogué), in an interview published in the United States:

When I suffered from insomnia I tried to forget myself, to forget my body, the position of my body, the bed, the furniture, the three gardens of the hotel, the eucalyptus tree, the books on the shelf, all the streets of the village, the station, the farmhouses. And since couldn’t forget, I kept on being conscious and couldn’t fall asleep. Then I said to myself, let us suppose there was a person who couldn’t forget anything he had perceived, and it’s well known that this happened to James Joyce, who in the course of a single day could have brought out Ulysses, a day in which thousands of things happened. I thought of someone who couldn’t forget those events and who in the end dies swept away by his infinite memory. In a word that fragmentary hoodlum is me, or is an image I stole for literary purposes but which corresponds to my own insomnia.⁵
Already in the literature of the first millennium there are references to people with prodigious memory, particularly in the Naturalis historia (Natural History) of Pliny the Elder (Gaius Plinius Secundus, 23–79 A.D.), a sort of encyclopedia that in 37 books describes everything from the geography, science, and technology to the agriculture, medicinal herbs, and insects of ancient Rome. In chapter 24 of book VII, on the topic of memory, Pliny mentions king Cyrus of Persia, who knew the names of all his soldiers; Scipio, who knew the names of all in Rome; Cineas, king Pyrrhus’s ambassador, who learned the names of all the Roman senators just one day after arriving in Rome; Mithridates Eupator, who administered justice in the 22 languages spoken in his empire; Simonides, inventor of mnemonics; or Charmadas the Greek, who could recite by heart any book from a library as though he were reading it.⁶


Pliny considers it a blessing to possess an extraordinary memory. In fact, he starts chapter 24 of book VII saying:
“Memoria necessarium maxime vitae bonum cui praecipua fuerit, haut facile dictu est, tam multis eius gloriam adeptis [As to memory, the boon most necessary for life, it is not easy to say who most excelled in it, so many men having gained renown for it].”⁷

Pliny also describes the fragility of memory, arguing that it can be lost, in whole or in part, due to illness, injury, and even panic. As an example he tells the story of a man who lost the capacity to name letters after being struck by a stone, and of another who forgot certain people after falling from a roof. He also mentions Messala Corvinus, the orator, who lost recollection of even his own name.

Borges, it is known, was fascinated by encyclopedias and by the Naturalis historia⁸ ( perhaps the first encyclopedia in history), which in fact he mentions in “Funes the Memorious”: Funes asks the narrator (Borges) for any Latin text, and Borges obliges with volume VII of Pliny’s encyclopedia and Quicherat’s Thesaurus, just so the rube will be rudely disappointed upon finding out that one cannot learn such a complicated language using only a book and a dictionary. On their next meeting, however, Funes welcomes Borges by reciting, mockingly, in perfect Latin: “ut nihil non iisdem verbis redderetur auditum” (which, literally translated, means: “Nothing that has been heard can be repeated with the same words”).⁹

Through Funes, Borges, just like Pliny, enters the realm of memory, though his reaction differs from the Roman’s in a crucial regard: while Pliny considers it a virtue to have a prodigious capacity to remember, Borges looks beyond and argues that an extraordinary memory can become a curse. Says Funes, midway through the story:

Más recuerdos tengo yo solo que los que habrán tenido todos los hombres desde que el mundo es mundo. . . . Mi memoria, señor, es como un vaciadero de basura.

[I alone have more memories than all men may have ever had since the world exists. . . . My memory, sir, is like a rubbish heap.]

Given their historical significance, Pliny’s stories are of undeniable value. It is, nonetheless, impossible to judge their veracity, and in fact the characters described in the Naturalis historia seem more legendary than real (perhaps arousing Borges’s curiosity even more). To a large extent this is due to the fact that many of Pliny’s descriptions are based on word-of-mouth information, inevitably altered in the telling. For example, when he describes cases of astonishing eyesight in chapter 21 of book VII, Pliny writes that Homer’s Iliad was written in such small script that the complete manuscript could fit in a nutshell; he also mentions a man called Strabo, who could recognize objects 135 miles away and who, during the Punic Wars, could sight and even count the enemy ships docked in Carthage from a promontory in Sicily.

The first properly documented case of extraordinary memory is that of Solomon Shereshevskii, studied by the celebrated Russian psychologist Alexander Luria starting in the 1920s. As Luria reports in his book The Mind of a Mnemonist: A Little Book about a Vast Memory, subject S. (as he refers to Shereshevskii to protect his name), unlike everyone else, had to make an effort if he wished to forget something. As we shall see in the following chapters, Shereshevskii possessed a very strong synesthesia—an involuntary link between different senses, like associating numbers with colors— that gave his memories a much richer content and thus made them easier to recollect. These associations, as well as the use of simple mnemonics, allowed Shereshevskii to remember long sequences of numbers and letters many years after first hearing them. After studying Shereshevskii for more than 30 years, Luria confessed his inability to find a limit to S.’s memory, a surprising statement considering that it comes not from an amateur but from one of the foremost psychologists of his time.

 Alexander Luria (1902–1977), Friedrich Nietzsche (1844–1900), and William James (1842–1910).

There are clear parallels between Shereshevskii and Funes, despite the fact that the former trained his memory based on his synesthesia while for the latter to remember everything was completely natural. It is, however, unlikely that Borges knew of Luria’s work, since Luria published his book (in English) only in 1968, more than 25 years after Borges wrote the story of Funes.

“Funes the Memorious” shows Nietzsche’s influence as well (as Roxana Kreimer describes in an interesting essay);¹⁰ in particular, Borges calls Funes “a precursor to supermen, a suburban, incomplete Zarathustra.” In a brilliant piece on the importance of forgetting, Nietzsche writes:

Imagine the most extreme example, a human being who does not possess the power to forget, who is damned to see becoming everywhere; such a human being would no longer believe in his own being, would no longer believe in himself, would see everything flow apart in turbulent particles, and would lose himself in this stream of becoming; like the true student of Heraclitus, in the end he would hardly even dare to lift a finger. All action requires forgetting, just as the existence of all organic things requires not only light, but darkness as well.¹¹

Borges’s fascination with the mind (in this philosophical context I again use “mind” rather than “brain,” though I make no distinction between the two) probably came from his father, a lawyer and psychology professor who introduced him to authors such as William James, considered by many to be the father of modern psychology. In The Principles of Psychology (1890), one of his fore- most works, James says this about memory:

If we remembered everything, we should on most occasions be as ill off as if we remembered nothing. . . . “The paradoxical result [is] that one condition of remembering is that we should forget. Without totally forgetting a prodigious number of states of consciousness, and momentarily forgetting a large number, we could not remember at all.”¹²

The relation to Funes, Shereshevskii, and Nietzsche is fascinating. Luria, for example, writes that Shereshevskii “was quite inept at logical organization.” Borges, in turn, says that Funes

había aprendido sin esfuerzo el inglés, el francés, el portugués, el latín. Sospecho, sin embargo, que no era muy capaz de pensar.

[had effortlessly learned English, French, Portuguese, Latin. I suspect, however, that he was not very capable of thinking.]

Again: I do not refer to Joyce, Pliny, Luria, Nietzsche, and James so as to question the originality of Borges’s story. On the contrary, these parallel writings provide a philosophical and scientific foundation in which Borges may have found part of his inspiration. Leaving aside the issue of whether Borges knew of Luria’s studies or not—I believe not—I cannot help noticing the uncanny lucidity with which he treats a topic as complex as memory in the context of a short story.

Going back to Funes and other people with extraordinary memory, we must mention Borges himself, who could quote whole passages in Spanish, English, German, and Anglo-Saxon, among other tongues. Though it is possible that blindness may have con- tributed to his incredible memory (not being distracted by visual stimuli, he could focus, like Democritus before him,¹³ on his thoughts and the stream of his remembrance), Borges’s youthful realization that he, like his father, would lose his eyesight took him on a monumental quest for knowledge while he could still see. María Kodama [his widow] remembers that, on one of her first encounters with Borges, he asked her to find an excerpt from a book. The fragment, the writer said, was on an odd-numbered page near the middle of the book. Kodama started to read a page at random and Borges, amazingly, guided her to the right page even though he had been blind for many years and—as he jotted on the first page—had read the book in 1916, decades before this encounter with Kodama.

FOOTNOTES

1. One of the main newspapers in Argentina.

2. Jorge Luis Borges, “Funes el memorioso,” in Obras completas (Buenos Aires: Emecé, 2007), vol. 1, pp. 583–590; subsequent quotations from this story are from the same source. Except where otherwise specified, all English translations of Borges in this book are by Juan Pablo Fernández.

3. I am not the first to ref lect on the roots of “Funes the Memorious” and its possible interpretations. In fact, I would like to give credit to those who have previously written on this topic (many of them cited in subsequent footnotes), and although any list I make will end up being unfair, since I will surely forget more than one reference, I would like to mention the essays by Víctor Zonana (“Memoria del mundo clásico en ‘Funes el memorioso’” [Remembrance of the classical world in “Funes the Memori- ous”], whose introduction includes an excellent summary of related work); Roxana Kreimer (“Nietzsche, autor de ‘Funes el memorioso’: Crítica al saber residual de la modernidad” [Nietzsche, author of “Funes the Memorious”: A critique of modernity’s residual knowledge]); Eduardo Mizraji (“Memoria y pensamiento” [Memory and thought], among other essays in the book Borges y la ciencia [Borges and science]); Patricia Novillo-Corvalán (“James Joyce, Author of ‘Funes the Memorious’”); Carlos Baratti (“‘Funes el memorioso’: Ficción que invita a ref lexionar acerca de la neurobiología de la memoria” [“Funes the Memorious”: A fiction that invites ref lection on the neurobiology of memory]); and the books by Iván Izquierdo (El arte de olvidar [The art of forgetting]), Guillermo Martínez (Borges y la matemática [Borges and mathematics]), and Diego Golombek (Cavernas y palacios: En busca de la conciencia en el cerebro [Caverns and palaces: Searching for consciousness in the brain]). Funes is, I would say, a classic reference in any book by an Argentine author on the topic of memory.

4. Jorge Luis Borges, “Fragmento sobre Joyce,” in Jorge Luis Borges en Sur, 1931–1980 (Buenos Aires: Emecé, 1999), pp. 167–169.

5. Jorge Luis Borges: Conversations, ed. Richard Burgin (Jackson: University Press of Mississippi, 1998), p. 166. This passage of the interview has been cited by Patricia Novillo-Corvalán in “James Joyce, Author of ‘Funes the Memorious’.”

6. Most of these characters had been earlier described by Cicero in his Tusculan Disputations. See Cicero, Tusculan Disputations, rev. ed., trans. J. E. King (Cambridge, MA: Harvard University Press; London: Heinemann, 1960).

7. Pliny, Natural History, vol. 2, trans. Harris Rackham (Cambridge, MA: Harvard University Press, 1942; London: Heinemann, 1947), pp. 562, 563.

8. Upon receiving the Cervantes Prize in 1979 (“a generous blunder that I shamelessly accept,” he said), Borges commented in an interview that with the prize money—a million pesetas, to be shared with Spanish poet Gerardo Diego—he planned to buy the Espasa Calpe encyclopedia, which he eventually received as a present from the publishers. Borges also had several editions of the Naturalis historia in his library, along with a 1907 edition of Sir Francis Galton’s Inquiries into Human Faculty and Its Development, on whose final page Borges transcribed chapter 24 of book VII of the Naturalis historia in the original Latin (along with a French translation on the first page).

9. In the context of Pliny’s paragraph this phrase can also be translated as “[Through memory] it is possible to repeat with the same words what has been heard.”

10. Roxana Kreimer, “Nietzsche, autor de ‘Funes el memorioso’: Crítica al saber residual de la modernidad” (Nietzsche, author of “Funes the Memori- ous”: A critique of modernity’s residual knowledge), in Jorge Luis Borges: Intervenciones sobre pensamiento y literatura (Buenos Aires: Paidós, 2000).

11. Friedrich Nietzsche, “On the Utility and Liability of History for Life,” in Unfashionable Observations, trans. Richard T. Gray (Stanford: Stanford University Press, 1995). In this essay Nietzsche refers to forgetting in a historical context, suggesting that man should not tie himself to the prejudices of History (a fundamental requirement for the creation of his famous “superman”).

12. William James, The Principles of Psychology, authorized ed., vol. 1 (New York: Henry Holt, 1890; repr., New York: Dover, 1950), pp. 680 – 681. The second half of the quotation is itself a quotation: Théodule Ribot, Les maladies de la mémoire (Paris: Librairie Germer Ballière, 1881), p. 46.

13. Democritus is known for conceiving atomic theory; legend has it that he gouged his eyes out in his garden so that contemplation of the external world would not disturb his meditations.

Tomado de: http://www.scientificamerican.com/article.cfm?id=borges-and-memory-encounters-with-human-brain-excerpt

 

Los dónde, cómo y cuándo de la memoria

«Cuando recordar no pueda» «¿dónde mi recuerdo irá?«Una cosa es el recuerdo»« y otra cosa recordar». Nuestro gran poeta Antonio Machado, bella y lúcidamente, distinguía así entre la acción de formar y la acción de recuperar el contenido de la memoria en su primer poema de `Cantares y Proverbios, sátiras y epigramas´. La investigación sobre la naturaleza de la memoria constituye una de las ramas actuales más fascinantes de la Biología humana. Cuando finalice el año 2012, durante el mismo, se habrán publicado más de 25.000 investigaciones sobre la memoria en revistas internacionales especializadas. Sin embargo, la complejidad del problema hará que nuestros conocimientos continúen siendo extremadamente insuficientes. 

 

MEMORIAS

¿Qué es la memoria?, ¿cuándo y cómo se forma?, ¿dónde se consolida y mediante qué procesos?, ¿cuántas clases de memoria existen?, ¿cómo se recupera o cómo se recuerda?, ¿cómo se pierde, desvanece o estropea?. Y, en todo ello, ¿qué acontecimientos celulares y moleculares ocurren?. Lo más evidente es el protagonismo e interacción de una buena parte de las neuronas del cerebro, cuyo número posiblemente alcanza la cifra de unos CIEN MIL MILLONES y sus conexiones diferentes podrían superar los CIEN BILLONES. Según Carl Sagan, tendríamos capacidad de almacenar en nuestra mente  una información equivalente a la de DIEZ BILLONES de páginas de una gran enciclopedia. Difícil empeño tienen, por tanto, los neurocientíficos ante sí para conocer y aclarar adecuadamente el tema.

 

De toda la ingente cantidad de estudios existentes vamos a referirnos sólo a dos de ellos muy recientes. El primero es una revisión publicada hace un mes en Neuroscience and Biobehavioral Reviews, por científicos americanos de las Universidades de Arizona y de Lehigh (Pensilvania), con el título (traducido) de `Formación, consolidación y transformación de la memoria´. El segundo,  de un grupo de neurocientíficos de la Universidad de Nueva York y de la Universidad de California, adelantado on-line, se publicará en un próximo número de los prestigiosos Proceedings of the National Academy of Sciences, y nos proporciona información novedosa a nivel molecular sobre el cuándo y el dónde de la formación de la memoria. Pero, primero, recordemos algunos puntos necesarios.

 

Aprender es adquirir nuevos conocimientos, habilidades, conductas o valores. La memoria hace que esas adquisiciones se conserven en el cerebro, por lo que podemos definirla como una función del cerebro que nos permite: a) codificar lo percibido por nuestros sentidos y consolidar el resultado de la codificación; b) almacenar la información, creando un registro permanente de la misma; c) recuperación o evocación posterior de la información almacenada, para crear una representación consciente o ejecutar una conducta aprendida.

 

Existen diversas divisiones de la memoria. Así tendríamos las episódica, semántica, perceptiva, operativa y procedimental.  Otra clasificación clásica es atender a su temporalidad: memoria a corto plazo (por ejemplo la operativa, de unos diez segundos), a medio plazo y a largo plazo. Hay datos que apuntan a que la localización cerebral es diferente para las diversas memorias cerebrales pero, en todo caso, el hipocampo es el gran protagonista relacionado con la memoria, aunque también participan otros sistemas corticales.  Es anecdótico, pero interesante que el hipocampo, donde radica la memoria espacial, es más grande en los taxistas de Londres que en el resto de ciudadanos londinenses. En la enfermedad de alzheimer se atacan las neuronas del hipocampo y ello es causa principal aunque no la única por lo que en dicha enfermedad se pierde la memoria. 

 

 

MODELOS

La memoria surge como resultado de sinapsis (contactos) repetitivas realizadas entre las neuronas. Como consecuencia de ello se crean las denominadas redes neuronales (o potenciación a largo plazo). Los recuerdos se crean cuando las neuronas integradas en un circuito refuerzan la intensidad o frecuencia de las señales que usan esas sinapsis. En las investigaciones sobre la memoria está siendo muy relevante el uso de animales simples que contienen solo unos cientos  de neuronas. Por ejemplo, la babosa marina Aplysia (también llamada liebre de mar). En la década de los 70 del pasado siglo constituyó la base de los trabajos de Erik R. Kandel, de la Universidad de Columbia, EEUU, por los cuales obtuvo el Premio Nobel de Medicina en el año 2000, en reconocimiento a sus descubrimientos sobre la transducción de señales en el sistema nervioso. Pero también hemos aprendido de otros animales. Así, en el Laboratorio de Neurobiología de la Memoria de la Facultad de Ciencias Exactas y Naturales de la Universidad de Buenos Aires vienen trabajando, desde 1985, con cangrejos, más concretamente  con el Chasmagnathus granulatus, que es un cangrejo semiterrestre que habita en las zonas de transición de agua dulce y salada de las costas del sur de Brasil, Uruguay y Argentina y presenta una gran sensibilidad y agudeza visual, de modo que los objetos en movimiento que estimulan la parte superior de su campo visual desencadenan un conjunto limitado de respuestas defensivas estereotipadas, fácilmente discernibles y medibles, además de que muestran una gran capacidad de aprendizaje para adecuar esas respuestas a distintas circunstancias y contextos. Aprovechando estas características los investigadores desarrollaron un modelo de aprendizaje y estudio de la memoria, estudiando su respuesta de escape a un estímulo visual de peligro. Ello permitió descubrir ciertas vías de señalización intracelular involucradas en la consolidación de la memoria y en la comunicación sinapsis-núcleo (es decir, periferia-centro de las neuronas), que dejaron clara la participación de una isoforma particular de la enzima PKA (proteína quinasa dependiente de AMP cíclico) en el proceso de la consolidación de la memoria. Algo similar sucedió con otra serie de moléculas ya conocidas de caminos de señalización celulares como NK-kB (factor nuclear kappa B), IKB (su inhibidor), IKK (quinasa de IKB), y las MAPKs (proteínas quinasas activadas por mitógenos). 

 

BABOSA

El trabajo recién publicado de los neurólogos de la Universidad de Nueva York y la Universidad de California, sigue la misma línea, utilizando babosas Aplysia californica, muy adecuadas porque sus neuronas son 10 a 50 veces más grandes que las de los organismos superiores y poseen una red relativamente pequeña de neuronas, lo que facilita el estudio. Según el investigador principal, Thomas Carew “Nuestros resultados proporcionan una comprensión más profunda de cómo se crean los recuerdos, ya que la formación de la memoria no es simplemente una cuestión de encendido y apagado de moléculas; por el contrario es el resultado de una compleja relación temporal y espacial de interacciones moleculares y de movimiento”. 

¿Qué han encontrado? Nuevamente, el protagonismo de las MAPK y una PKA, que ya se sabían involucradas en muchas formas de memoria y plasticidad sináptica — es decir, cambios en el cerebro que ocurren después de activación neuronal. Pero, sobre todo, han aclarado cómo y dónde interactúan estas proteínas. Ambas moléculas han demostrado estar involucradas en la formación de la memoria de sensibilización. Y han hallado que MAPK y PKA coordinan su actividad tanto espacial y temporalmente en la formación de recuerdos. Específicamente, en la formación de la memoria a medio plazo (por ejemplo, horas),  largo plazo (por ejemplo, días) y recuerdos, participan las actividades MAPK y PKA, y en concreto las MAPK estimulan la acción de la PKA. Por el contrario, para las memorias a corto plazo (por ejemplo, menos de 30 min) sólo se activa la PKA por acción normal del AMP cíclico, sin que participen las MAPK.

 

Un paso más en lo que, sin duda,  será una lenta respuesta a la compleja pregunta de dónde, cómo y cuando se forman y funcionan las diferentes memorias y que moléculas y células y en qué orden intervienen.

 

Más en: http://www.pnas.org/content/early/2012/10/11/1209956109.short

Tomado de:  http://cienciaysalud.laverdad.es/biociencias/biologia-humana/los-donde-como-cuando-memoria-article.html

Leen nuestros sueños

Científicos japoneses han descubierto cómo saber lo que soñaron las personas.

El equipo, liderado por Yukiyasu Kaitani del Laboratorio Computacional de Neurociencias ATR en Kyoto, Japón, se basó en imágenes de la actividad neuronal del cerebro de unos pacientes. Así, se escanearon a tres personas mientras dormían, en lo que simultáneamente se grababan sus ondas cerebrales utilizando un electroencefalograma.

Los investigadores despertaban a los participantes cuando detectaban que los patrones del cerebro se asociaban con el inicio de un sueño, y les preguntaban sobre lo que acababan de soñar, para después volverse a dormir.

Esto fue hecho en bloques de tres horas, repetido entre siete y diez veces en diferentes días, con cada participante. Durante cada bloque, los estudiados se despertaban diez veces por hora.

Cada voluntario reportó tener seis o siete sueños visuales en cada tiempo, dándole a los investigadores un reporte de 200 sueños.

La mayoría de los sueños reflejan experiencias que vivimos durante el día o sobre otros momentos, pero con algo inusual en ellos, como soñar que platicas con un personaje famoso.

Los investigadores extrajeron palabras clave de los reportes verbales dados por los participantes, como "auto", "hombre", "mujer", o "computadora", conceptos que aparecían con más frecuencia en las descripciones de los participantes.

Kamitani seleccionó fotografías que representaban cada categoría, y escaneó el cerebro de los participantes mientras las observaban. De esta manera, comparó la actividad cerebral de estas imágenes con los patrones de actividad grabados durante la etapa del sueño de los voluntarios.

En 2008, el equipo japonés reportó que podía decodificar la actividad cerebral asociada con el proceso de reconstrucción de las imágenes mostradas a los participantes. Ahora, han descubierto que la actividad en ciertas partes del cerebro puede predecir certeramente el contenido de los sueños del participante.

"Creamos un modelo que predice la categoría que va a existir en el sueño" dijo Kamitani a Scientific American. "Analizando la actividad cerebral durante nueve segundos antes de despertar al sujeto, pudimos predecir si había un hombre o no en el sueño, por ejemplo, con una eficacia del 75-80 por ciento".

El estudio sugiere que la actividad de soñar involucra la misma actividad en áreas del cerebro en las que se involucra la capacidad visual de imaginar.

Katamani y sus colegas, ahora están tratando de recolectar la misma información en la etapa del sueño con movimientos oculares rápidos (REM, por sus siglas en inglés), el estado más profundo del sueño.

"Esto es más complicado porque tenemos que esperar al menos una hora de sueño para que el sujeto llegue a esa etapa" menciona Kamitani.

Pero vale la pena, asegura, pues ?conocer más sobre el contenido de nuestros sueños nos ayudará a entender mejor la función de soñar?, dice Kamitani.

Tomado de: http://www.muyinteresante.com.mx/ciencia/517003/logran-decodificar-suenos-predecir-se-sonar/