Posts Tagged ‘Christoph Nissen’

How to Hack Your Unconscious…to Boost Your Memory and Learn Better

August 5, 2018

This post is based on a feature article with the same title as this post by Emma Young in the 28 July 2018 issue of the New Scientist. Much of the learning process goes on deep in the mind. If you could improve the unconscious processing and retrieval of memories, you could game the system. Here are the top tips to improve how you recall facts.

If you’re learning facts such as foreign phrases or historical dates, giving our study a boost could be as simple as taking a break. Lila Davachi of New York University found that breaks help to consolidate memories, improving recall later. But for a time out to work, brain cells different to those used during the learning period need to be activated. So, try not to think about what you have just been working on.

It is even better to sleep on it. It is well established that the brain processes memories during sleep, but it will do this more effectively if you leave the optimum time between learning and sleeping. Christoph Nissen at the University of Bern found that a group of 16 and 17 year olds performed best on tests of factual memory if they studied the material mid-afternoon, but they acquired skills involving movements faster if they practiced in the evening. So it appears that the “critical window” between learning and sleep is shorter for movement-related learning that for other types of memory. It isn’t clear whether adults can benefit as much as teenagers from these windows. Nissan says, “There is evidence that adolescents have a higher capacity to learn—and they sleep better.” Moreover, after about age 60 adults generally learn better in the morning.

Bjorn Rasch of the University of Fribourg, Switzerland is investigating another way to boost learning during sleep. He has conducted studies showing that adult language learners remember more when played recordings of foreign words while sleeping. He says, “The literature on targeted memory reactivation is growing rapidly. Most findings are positive.” But it is important that the words are played during non-REM, slow-wave sleep, when factual memories are consolidated. And the volume of the recordings should not be so loud that it disrupts. You could also try using scents to cue learning in sleeping brain. Rasch has found a boost to memory in people who smelled roses while learning a task and then again during slow wave sleep.

Perhaps the most surprising effect is the placebo effect. Yes, there is a placebo effect in memory. In this study volunteers who had to answer multiple-choice questions did significantly better if told that the correct answer would be flashed subliminally just before the question. They were not. The improved performance was all the result of the placebo effect. The researchers think it worked by reducing performance anxiety and priming people for success. However, HM still wants to find successful replications of this experiment.

HM would be remiss if he did not mention that there is an entire category of posts titled Mnemonic Techniques. Included here are classical techniques and techniques develop for remembering numbers. There are also posts here titled “Moonwalking with Einstein,” and “How to Become a Memory Grandmaster’ that describe what can be done with these techniques as well as professional memory competitions.

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We’ve Finally Seen How the Sleeping Brain Stores Memories

December 29, 2017

The title of this post is identical to the title of a post by Jessica Hamzelou in the 7 October 2017 issue of the New Scientist. To do this research needed to find volunteers who were able to sleep in an fMRI scanner. They needed to scan 50 people to find the 13 who were able to do so. These volunteers were taught to press a set of keys in a specific sequence. It took each person between 10 to 20 minutes to master this sequence.

Once they learned this sequence they each put on a cap of EEG electrodes to monitor the electrical activity of their brains, and entered an fMRI scanner, which detects which regions of the brain are active.

There was a specific pattern of brain activity when the volunteers performed the key-pressing task. Once they stopped, this pattern kept replaying in their brains as if each person was subconsciously reviewing what they had learned.

The volunteers were then asked to go to sleep, and they were monitored for two and a half hours. At first, the pattern of brain activity continued to replay in the outer region of the brain called the cortex, which is involved in higher thought.

When the volunteers entered non-REM sleep, which is known as the stage when we have relatively mundane dreams, the pattern started to fade in the cortex, but a similar pattern of activity started in the putamen, a region deep within the brain
(eLife, doi.org/cdsz). Shabbat Vahdat, the team leader at Stanford University, said that the memory trace evolved during sleep.

The researchers think that movement-related memories are transferred to deeper brain regions for long-term storage. Christoph Nissen at University Psychiatric Services in Bern Switzerland says, “this chimes with the hypothesis that the brain;’s cortex must free up space so that it can continue to learn new information.

The title of this post is identical to the title of a post by Jessica Hamzelou in the 7 October 2017 issue of the New Scientist. To do this research needed to find volunteers who were able to sleep in an fMRI scanner. They needed to scan 50 people to find the 13 who were able to do so. These volunteers were taught to press a set of keys in a specific sequence. It took each person between 10 to 20 minutes to master this sequence.

Once they learned this sequence they each put on a cap of EEG electrodes to monitor the electrical activity of their brains, and entered an fMRI scanner, which detects which regions of the brain are active.

There was a specific pattern of brain activity when the volunteers performed the key-pressing task. Once they stopped, this pattern kept replaying in their brains as if each person was subconsciously reviewing what they had learned.

The volunteers were then asked to go to sleep, and they were monitored for two and a half hours. At first, the pattern of brain activity continued to replay in the outer region of the brain called the cortex, which is involved in higher thought.

When the volunteers entered non-REM sleep, which is known as the stage when we have relatively mundane dreams, the pattern started to fade in the cortex, but a similar pattern of activity started in the putamen, a region deep within the brain
(eLife, doi.org/cdsz). Shabbat Vahdat, the team leader at Stanford University, said that the memory trace evolved during sleep.

The researchers think that movement-related memories are transferred to deeper brain regions for long-term storage. Christoph Nissen at University Psychiatric Services in Bern Switzerland says, “this chimes with the hypothesis that the brain;’s cortex must free up space so that it can continue to learn new information.

Why Do We Sleep?

December 10, 2016

The question raised by the title of this post is highly relevant given that about one-third of our lives is spent sleeping.  A brief piece  titled “A bad night’s sleep messes with your brain’s memory connections in the In Brief Section of the August 27, 2016 Edition of the “New Scientist” provides a compelling answer.  The piece begins with the following sentence, “This is why you feel so awful after a bad night’s sleep—your brain is jammed with yesterday’s news.”

The research was done by Christoph Nissen and his team at the University Medical Center in Freiburg, Berman.  They examined the brains of 20 people after they’d slept well, and after a night of disruption.  They found that after a bad’s night sleep, people had higher levels of theta brainwaves, and it was easier to stimulate their brains using magnetic pulses (“Nature Communications.” DOI”10.1038/ncomms12455).

The findings support the theory that sleep serves to weaken memory connections, making way for new ones.  Nissan says that without this synaptic downscaling, the brain loses the capacity to for novel connections, impairing the encoding of novel memories.  The theory is that sleep evolved so that connections in the brain can be pruned down during slumber, making room for fresh memories to form the next day.

The idea that sleep is important to memory is not new.  And memory is certainly important enough that we need to devote about one-third of our lives supporting it. Of course, it is likely that memory is not the only capacity to benefit, but it is likely that other capacities that benefit are closely related to memory.

© Douglas Griffith and healthymemory.wordpress.com, 2016. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Douglas Griffith and healthymemory.wordpress.com with appropriate and specific direction to the original content.