Posts Tagged ‘neuroscience’

Brain Science: The Dog Ate My Striatum…

Thursday, January 21st, 2010

Scientists have shown a connection between the size of three particular brain regions and the ability to adapt quickly and perform well on a new set of abstract mental tasks – in this case, a video game (the article makes too much, I think, of the fact that the study used a video game as its measure of learning.)

Brain Regions Linked to Learning

Brain Regions Linked to Learning

The team set out to discover whether physical characteristics in the brain played a role in the variability in learning rates.

“Our animal work has shown that the striatum is a kind of learning machine – it becomes active during habit formation and skill acquisition,” one of the study’s co-principal investigators, Ann Graybiel of the Massachusetts Institute of Technology, said in the news release. “So it made a lot of sense to explore whether the striatum might also be related to the ability to learn in humans.”

Thirty-nine subjects, ten men, twenty-nine women, ages 18 to 28, were recruited at the University of Illinois; none had played video games for more than three hours a week in the past two years.

RPI
The video game Space Fortress can be manipulated to test various aspects of cognition.


After brain mapping and measuring with an MRI, each subject played a specially created video game for 20 hours. The researchers instructed some players to focus on scoring as many points as possible, and others to shift their priorities between several goals.

Subjects with a more voluminous nucleus accumbens did significantly better in the early stages of training. Those with larger caudate nucleus and putamen, performed better when shifting strategies.

“These are people who had healthy brains,” Erickson said. “These aren’t learning-disabled people. But we were still able to distinguish essentially who would be more affected by the training in this video game.”

The nucleus accumbens has been previously linked to the brain’s emotional response to reward and punishment; more volume here indicates a greater capacity for absorbing the frustrations of the early learning process.

“The putamen and the caudate have been implicated in learning procedures, learning new skills, and those nuclei predicted learning throughout the 20-hour period,” said the University of Illinois’ Arthur Kramer, another co-principal investigator.

“The fact that we could explain more than 20 percent of the variance in learning rates by measuring the volume of only two or three brain regions is actually quite impressive,” Erickson said. “There must be several other brain regions contributing to performance in learning. These other regions are things that other studies will have to track down.”

Read the full article here: Big Brain For Video Games

DNA Differences in The Brain

Thursday, January 7th, 2010

Neuroscience pioneer Fred Gage was the first to demonstrate that the adult human brain produces new brain cells. He’s now discovered that the DNA in brain cells can differ from the DNA in the rest of the body. Not only that, but the DNA in one brain cell may be different from that in another.

Gage postulates that this genetic flexibility could be a mechanism by which we (our brains) adapt to life’s unpredictable challenges: http://tinyurl.com/brain-dna

Neurogenesis And Memory

Tuesday, November 17th, 2009

Kaoru Inokuchi, a neuroscientist at the University of Toyama in Japan, and his team have shown that new brain cells in the hippocampus help clear away short term memories that have been passed along to long term storage.

It’s been known for a while that the hippocampus stores memories for a while then lets them go. Some memories make it into long term memory, some don’t. For a while, memories can be stored both in long term memory and the hippocampus.

Inokuchi and his colleagues suppressed neurogenesis in rats after inducing a “shock” memory. They found that the rats accessed hippocampal memory to remember the “shock” response. In contrast, rats with normal neurogenesis accessed long term memory for the shock response, indicating that neurogenesis had helped displace the “shock” memory from the hippocampus.

It had been previously theorized that neurogenesis helped form and consolidate memories in the hippocampus, but things now seem more complex.

“Our findings do not necessarily deny the important role of neurogenesis in memory acquisition,” Inokuchi says. “Hippocampal neurogenesis could have both of these roles, in erasing old memories and acquiring new memories.”

Success And Perseverance

Monday, August 3rd, 2009

I’m posting a link to this article from the Boston Globe: “The Truth About Grit

The story reports on a growing focus of research into the trait of “grit” and how it relates to success in life.

The story explains how the relationship between IQ and success came to dominate the focus of psychologists, in part because it was easy to test for. Recently, researchers have becom interested in better defining and measuring “grit” in the belief that it may provide a better indicator for success than IQ.

It certainly seems to make a lot of common sense that an intelligent person can fail simply through lack of resolve, and that a less intelligent person can succeed through dint of persistence.

Quite apart from general interest, I have another reason for posting about this story. It also strikes me that dual n-back training can be useful in training both intelligence and persistence or “grit.” It’s certainly not possible to succeed at n-back training without having or developing a fair degree of perseverance!

Creativity And High IQ

Tuesday, May 26th, 2009

Published over on our sister blog at mindevolvesoftware.com:

Bright Minds Create Differently

A study by the MIND Research Network’s Rex Jung, an assistant professor at The University of New Mexico Department of Neurosurgery, shows that high IQ (120 and above, or the top 9%) minds operate differently when forming creative thoughts.

By scanning the brains of 56 college-age students he found that a chemical associated with creativity called N-acetylaspartate, or NAA, works more discretely in the frontal lobe of those with high IQs than it does in those with average IQs.

“It’s a funny kind of finding, and I wish I knew why,” Jung said…

Read more

Does Neurogenesis Lead to Memory Loss?

Thursday, January 15th, 2009

I posted about this over at our sister blog – The Science of the Evolving Mind – I hadn’t considered the question until I came across the research suggesting an answer…

Could new cell formation in the hippocampus lead to the loss of existing memories?

Scientists from Korea have demonstrated that mice with a contextual fear memory retain that fear memory whether neurogenesis has been halted or not.

So, new brain cell growth doesn’t necessarily displace existing memories.

Good news for those of us intent on stimulating new neural growth!

Doidge – Part 3 – The Science of Brain Training

Friday, November 21st, 2008
Norman Doidge: The Brain That Changes Itself

Norman Doidge: The Brain That Changes Itself

(This post is adapted from an entry on our sister blog at mindevolvesoftware.com)

In Chapter three of his book, Doidge focuses on the remarkable career and contributions to the understanding of brain science of Michael Merzenich , a scientist driven by the desire to solve real world problems (like understanding autism) and not content to leave the solutions to others. With Merzenich, a practical solution is part of the scientific challenge.

This section of the book is a must-read for anyone interested in the science behind brain plasticity, brain training, learning and learning dysfunctions, autism, and brain aging. But I will highlight some of the particularly luminous thoughts:

Merzenich: The brain is “like a living creature with an appetite” what we feed it to some extent determines how it thrives. When we engage our brains it matters what we do with them.

Shifting brain maps: By microscopic mapping of the surface of the brain, Merzenich showed that the areas of the brain controlling and responding to things like touch shifted over time depending upon what the brain needed to do with them. (Use two fingers together all the time, the brain maps for those two fingers become merged.)

Competitive plasticity: The brain is constantly assessing how important it is to allocate space to certain skills and functions. The more we demand of a certain skill (like playing the piano) the more space and brain power it gets. The less we use a certain function or skill, the more it loses its brain real estate to other functions.

The role of close attention in plastic change: Merzenich found that repetition alone isn’t enough for plastic change. When monkeys in his research performed tasks repeatedly their brain maps changed, but only if they paid close attention to the task did the changes hold long term. (This is a underpinning tenet to the Brain Fitness Pro training exercise and crops up on the training blog all the time.)

Why children learn so easily… and why adults don’t. Brain-derived neurotrophic factor or BDNF plays a critical role in triggering the brain’s ability to absorb and learn. In children during the critical period of learning the child’s body releases a lot of BDNF, keeping the brain constantly stimulated to absorb new information. Children’s brains are engaged and absorbent throughout this period. But at the end of the critical period, the body releases a whole lot more BDNF, a trigger that effectively shuts down the critical period and puts an end to this process.

It may seem odd that we’re designed to stop learning effortlessly past a certain point, but it would be difficult to function as an adult if we were constantly distracted and unable to determine priorities and accumulate the wisdom of trial and error.

Restimulating plasticity in adults: As Doidge puts it, “We rarely engage in tasks in which we must focus our attention as closely as we did when we were younger.” Merzenich found that the brain’s ability to grow new nerve cells, forge plastic change, and learn new skills wasn’t completely shut off in adults, but required certain conditions to be opened up again. The first condition is highly focused attention. The second is reward or satisfaction, which can come from novelty, pleasure, or a sense of achievement. (Again, these are foundations of the Brain Fitness Pro design.)

In Merzenich’s own words: “Everything that you can see happen in a young brain can happen in an older brain.”

This phase of Merzenich’s career lead him to help found Posit Science, a company that publishes brain training software to help children with learning disabilities and to provide brain training for older people who are losing or don’t want to lose memory function or mental sharpness as they age.

(As I’ve written elsewhere, Posit Science seems to have great products, but they’re unfortunately very expensive, and prohibitively expensive in many situations that could really help people. A full program for an adult costs over $600. That’s why I believe that Brain Fitness Pro should remain affordable, in order to bring these kinds of benefits to those who need them but just don’t have hundreds of dollars to spend.)

Related posts:

Building a Better Brain — in the second case study Doidge focuses on Barbara Arrowsmith Young’s discovery that learning disabilities can be mitigated by training the weaker areas of the brain to be stronger.

Part 2 – Rewiring balance — Doidge explores the incredible contributions of Michael Merzenich (the founder of Posit Science).