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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