Posts Tagged ‘Jessica Hamzelou’

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.

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Brain Implant Boosts Human Memory by Mimicking How We Learn

November 18, 2017

The title of this post is identical to the title of a News piece by Jessica Hamzelou in the 18 November 2017 issue of the New Scientist. The team doing the research says,
“Electrical shocks that simulate the patterns seen in the brain when you are learning have enhanced human memory for the first time, boosting performance on tests by up to 30%.” Dong Song of the University of Southern California says, “We are writing the neural code to enhance memory function. This has never been done before.”

The device mimics brain signals associated with learning and memory, stimulating similar patterns of brain activity in the hippocampus via electrodes. This device was implanted in 20 volunteers who were already having electrodes placed in their brains to treat epilepsy.

The first stage was to collect data on patterns of activity in the brain when the volunteers were doing a memory test. The test involved trying to remember which unusual, blobby shapes they had been shown 5 to 10 seconds before. This test measures short- term memory. People normally score around 80% on this task.

The volunteers also did a more difficult version of the test, in which thy had to remember images they had seen between 10 and 40 minutes before. This measures working memory.

Then the team used this data to work out the patterns of brain activity associated with each person’s best memory performances. The group then made the device electrically stimulate similar brain activity in the volunteers while they did more tests.

A third of the time, the device stimulated the participants brains in a way the team thought would be helpful. Another third of the time, it stimulated the brain with random patterns of electricity. For the remaining third of the time, it didn’t stimulate the brain at all.

Memory performance improved by about 15% in the short-term memory test and around 25% in the working-memory test when the correct stimulation pattern was used, compared to no stimulation at all. Some improved by 30%. Random stimulation worsened performance. Song says the “It is the first time a device like this has been fond to enhance an aspect of human cognition.”

Chris Bird of the University of Sussex, UK thing that such a device may be useful for treating medical conditions. However the prosthesis wouldn’t be able to replace the hippocampus entirely. He says, “The hippocampus is quite a large structure and they are only recording from a very small area.’

Now the team is working on ways to enhance other brain functions. Song says,”The approach is very general . If you can improve the input/output of one brain region, you could apply it to other brain regions. Good candidates for this are skills localized to particular parts of the brain, such as sensation of the outside world, vision, and how we move. Enhancing these might improve a person’s hand-eye coordination. However, cognitive functions like intelligence involve many brain regions working together so wouldn’t make good targets.

There are individuals like Kurzweil who think that their brains can be uploaded to silicon, or that direct connections can run between computers and the brain. What these individuals are ignoring is that communications must be in the language of the brain. The research presented here shows what must be done to communicate and exchange information to the brain.

© Douglas Griffith and healthymemory.wordpress.com, 2017. 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.

To Treat Chronic Pain, Look to the Brain Not Body

December 3, 2016

This post is taken from a Feature Article by Jessica Hamzelou, “Hurt Blocker:  To treat chronic pain, look to the brain not body” in the 26 November 2016 Issue of the New Scientist.  It is becoming increasingly clear that the root causes of chronic pain will require more than drugs to break the cycle.  The answer lies in how the brain processes pain.

As has been mentioned in previous posts, there are two pathways for pain.  One is from the actual physical injury, whereas there is a second pathway for emotion linked pain.  Recent research indicates that signals from psychological pain networks may take over when the problem becomes chronic.

People can be trained to more directly influence their own brain activity and, potentially, turn down the pain signal.  Neurofeedback can be provided by placing electrodes on participants’ scalps that provide a real-time display of the brain’s electrical activity.  People can learn to alter their brain activity to dial down their pain.  Initial research suggest that neurofeedback might be useful for people with fibromyalgia, as well as those with chronic pain resulting from spinal cord injuries and cancer.

Mindfulness meditation can achieve something similar.  The goal is to achieve a state of ‘detached observation,’ which can help cope with pain.  Studies have suggested that it improves  various types of chronic pain, including fibromyalgia and lower back pain.  A study of 17 people who practiced mindfulness-based stress reduction found that, over time, meditators experienced increases in grey matter in regions of their brains involved in learning, memory, and emotion.  All of these influence pain perception.

The following is taken from a previous healthy memory blog post “Pain and the Second Dart:”
“A great way to return your mind to its “ground state,” neither overexcited nor torpid, simply alert and open, is to become aware of the natural rhythm of the breath as you inhale and exhale.  This is focused attention, prerequisite for the second state of mindfulness meditation:  insight.

Start by focusing on the sensation of the breath entering and leaving you body at the nostrils.  Remember, you are observing your breathing rather than controlling it.  Follow each inhalation and exhalation from the start to the finish.  Notice any slight gap between the in-breath and out-breath.

Don’t be hard on yourself if your mind wanders or you get distracted by a noise.  This is all perfectly normal.  Just remind yourself:  “That’s how the mind works,” and return to the breath.  With repetition, you will get better at noticing when you have lost focus and develop greater mindfulness of the present moment.

Now that you have quieted your mind, allow your attention to broaden.  Whenever a positive or negative feeling arises, make it the focus of your meditation, noticing the bodily sensations associated with it:  perhaps a tightness, the heart beating faster or slower, butterflies in the stomach, relaxed or tensed muscles.  Whatever it is, address the feeling with friendly, objective curiosity.  You could silently label whatever arises in the mind, for example:  “There is anxiety,” “There is calm,: There is joy,” “There is boredom.”   Remember, everything is on the table, nothing is beneath your attention.
If you experience an ache or a pain, stitch or any other kind of discomfort, treat it in exactly the same way.  Turn the spotlight of your attention on the sensation but don’t allow yourself to get caught up in it.  Imagine that on the in-breath you are gently breathing air into the location where the sensation is strongest, then expelling it on the out-breath.  You may notice that when you explore the sensation with friendly curiosity—not trying to change it in any way, neither clinging to it or repressing it—the feeling will start to fade of its own accord.  When it has gone, return your full attention to your breath.

Mindfulness instructors will sometimes talk about “surfing” the wave of an unpleasant sensation such as pain, anxiety, or craving.  Instead of allowing yourself to be overwhelmed by the wave of feeling, you get up on your mental surfboard and ride it.  You experience it fully, but your mind remains detached, dignified, and balanced.  Knowing that the power of even the most fearsome wave eventually dissipates, you ride it out.

If a thought, emotion, or feeling becomes too strong or intrusive, you can always use the breath as a calm refuge, returning you whole attention to the breathing sensations at your nostrils.  Similarly if you feel you can’t cope with a pain such as stiffness in your legs, neck, or back, shift your posture accordingly.  But make your attention move to a mindful close rather than a reflex, and make the movement itself slow and deliberate.”
A previous healthy memory blog post, “Controlling Pain in Our Minds” explores this topic further and discusses the possibility of there being two different neural pathways processing the ‘two darts’.”

© 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.

Controlling Pain in Our Minds

May 16, 2015

This blog post is based on an article in the New Scientist (17 Jan 2015, p.10) by Jessica Hamzelou titled “Pain Really Can Be All in Your Mind.”  She reported research  by Tor Wager at the University of Colorado Boulder that was published in the Public Library of Science (PLoS Biology, dpi.org/x55).    They used fMRI to examine the brain activity  of 33 healthy adults.  They first watched the changing activity  as they applied increasing  heat to the participants arms.  A range of brain structures lit up as the heat became painful.  This was a familiar pattern of activity  called the neurologic pain signature.

The researchers wanted to know if the participants  could control the pain by thought alone.  They asked the participants to rethink their pain either as blistering heat, or as a warm blanket on a cool day.  Although the participants couldn’t change the level of activity in the neurologic pain signature, they could alter the amount of pain they felt.  When they did this, a distinct  set of brain structures linking the nucleus accumbens and the ventromedial prefrontal cortex became active.

Vanaia Apkarian of Northwestern University noted,”It’s a major finding.  For the first time, we’ve established  the possibility of modulating pain through two different pathways.”  Brain scans can compare the strengths of activation of these two brain networks to work out how much pain has a physical cause, and how much is due to their thoughts and emotions.

These finding built on prior work by Apkarian’s team, who discovered that chronic back pain seems to be associated with a pattern of brain activity not usually seen with physical pain.  The brain regions active in Apkarian’s patients are the same as those active  in the participants controlling pain in Wager’s study.

It is possible that in chronic pain conditions, psychological pain might overtake physical pain as the main contributor to the overall sensation.  This might be the reason that traditional pain relief such as opiods don’t offer much relief from pain.

Hamezelou notes, “Wager’s study suggests that cognitive therapies and techniques such as nuerofeedback—where people learn to control their brain activity by watching how it changes in real time—might offer a better approach.”

Ben Seymour, a neuroscientist at the University of Cambridge notes, “in the next five to 10 years, we’ll see a huge change in the way clinicians deal with pain.  Rather than being passed on what the patient says, we’ll be building  a richer picture of the connections in the person’s brain to identify what type of pain they have.