Posts Tagged ‘neurogenesis’

Neurogenesis For Better Memory

Sunday, March 6th, 2011

New research into neurogenesis, brain plasticity and memory gives a clue as to how our brains form memories using new brain cells and a tantalizing promise of developing a better memory.

Working with mice, researchers tested how well the mice remembered the location of their last meal (by seeing how easily they could return to the site). When the food locations were well separated the mice did fine. But when the researchers placed the food quite close to a previous location, one group of mice became confused. In these mice the researchers had disabled hippocampal neurogenesis, disrupting the ability of the mice brains to generate new brain cells. Neurogenesis, it seemed, led to better memory formation.

While the function of newborn brain cells is not well understood, many researchers now believe that new cells help in memory formation, but not all memory formation — contextual memories that can get easily confused (like where you left the car keys).

We can encourage neurogenesis through diet, aerobic exercise, and brain exercise.

“We are closer to understanding how memories are truly formed and stored in the brain,” says Craig Stark, director of the Center for the Neurobiology of Learning and Memory at the University of California, Irvine. “If we want to try to help get better memories, we’d darn well better know how the system works.”


Neurogenesis occurs in the hippocampus, a brain region important for learning and memory. The hippocampus encodes and prepares new memories for storage, then dispatches them to different parts of the brain. In 1998, scientists showed that the hippocampus produces thousands of new brain cells each month. The nursery for nerve cells is a peanut-sized region of the hippocampus called the dentate gyrus. Approximately 3 to 5 percent of the cells in the dentate gyrus are developing, says Fred Gage, a neuroscientist at the Salk Institute for Biological Studies in La Jolla, Calif.

Many scientists think brain cells produced by neurogenesis in the dentate gyrus are crucial for better memory formation. New nerve cells, “neuronal progenitor cells,” aren’t connected to the brain’s neural network. Over their first month, the new cells begin to mature and establish exploratory connections with the surrounding brain tissue, beginning to elongate and to look more like nerve cells in the rest of the brain.

When the new brain cells finish maturing they integrate into the rest of the hippocampus, where they remain for a lifetime. “Most of the dentate gyrus is formed after birth,” Gage says. “A lot of it is formed in the first four years of life. That’s when you’re getting your baseline of memories. Then a low level of neurogenesis persists.”

Better Memory

Gage and others hypothesize that these adult-born nerve cells assist in a particular kind of memory called pattern separation, which keeps similar experiences from overlapping.

“New neurons are helping to distinguish between events that are close to each other,” Gage says. “It’s like a bar code. You put the bar code of the [memory] into the dentate. It’s coded with lots of information.”

For better memory formation, the brain stores the context of the memory, says Raymond Kesner, a psychology professor at the University of Utah in Salt Lake City. “If you try to remember a story, time and place will always be important.”

In experiments described in 2008 in Hippo­campus, Kesner’s team demonstrated that rats with a healthy dentate gyrus had a better memory for object locations than those with a disabled dentate gyrus. His experiments support the idea that neurogensis in the dentate gyrus helps the brain remember the context of a memory.

In 2010, in Hippocampus, Stark and his colleagues new neurons in the dentate gyrus of aged brains are relatively inactive or slow to make connections. In older tissue, the newborn nerve cells appear to require greater contrasts among images and experiences before reacting and capturing a memory. As people age, Stark says, “we seem to be less good about details and specifics.”

How To Improve Memory

Researchers have begun to pinpoint factors that decrease neurogenesis in the dentate — including stress, alcohol consumption and, according to a study in Neuroscience Letters in 2010, a high-fat diet. On the plus side physical activity and working memory brain training exercises can increase neurogenesis and lead to a better memory.

Henriette van Praag of the Neuroplasticity and Behavioral Unit at the National Institute on Aging in Bethesda, Md. reported last year in the Proceedings of the National Academy of Sciences that mice that exercise regularly perform better in pattern separation tests.

Compounds in fruits, vegetables and herbs also appear to enhance the survival of new brain cells. Omega-3 fatty acids found in fish such as salmon and sardines, flavonoids found in non-green vegetables and berries, and curcumin, a common component of curry. (Epicatechin, from green tea and chocolate, doesn’t appear to promote the birth of neurons directly but does encourage existing neurons to sprout more connections to neighbors, improving memory. The effect is particularly strong when combined with exercise.)

And as MindSparke trainees know so well, brain training with intensive working memory exercises promotes neurogenesis and brain fitness, significantly boosting our memory and brain power.

Brain Food, Mood, Brain Fitness & Neurogenesis

Thursday, February 24th, 2011
leptin and brain fitness

Leptin And Brain Fitness

This post could be otherwise titled: what is Leptin and what does it have to do with brain training and brain fitness?

Leptin (from the Greek leptos meaning thin) is a protein hormone produced from fat tissue; it is critical in regulating appetite and metabolism.

As we consume calories our bodies produce Leptin. In turn our hypothalamus reacts to the Leptin by inducing the “I’m full” feeling and by increasing energy consumption, particularly from stored fat. For the Leptin regulation system to operate effectively, our Leptin receptors need to be working well. But toxins and other harmful stressors can damage our brain’s Leptin receptors causing Leptin resistance. Leptin resistance is bad.

New research shows that Leptin has a tremendous impact on brain functioning and brain health. Leptin is essential to neurogenesis (the development of brain cells), brain nerve fiber growth, the formation of brain synapses, neuron excitability, neuro-protection and the regulation a compound that accumulates in the brains of people with Alzheimer’s!. A well-functioning Leptin system improves brain fitness, mental sharpness, leads to better memory, and enhances mood. Leptin may also protect the brain against the development of mood and neurodegenerative disorders, such as Alzheimer’s disease.

To balance your leptin levels naturally:
  • Decrease sugar and grain consumption: sugar, high fructose corn syrup and heavy doses of grains, such as wheat, oats, rice, and starchy vegetables, will increase leptin resistance.
  • Steer clear of trans-fats.
  • Eat plenty of non-starchy vegetables and healthy fats, such as avocados, extra-virgin coconut and olive oils, grass-fed meat, free-range eggs, almonds, Brazil nuts, pecans, walnuts, and hemp, flax and chia seeds.
  • Do high-intensity exercise for short stints. This will stimulate large secretions of human growth hormone, which boost fat-burning mechanisms and help to regulate leptin levels.
  • Get a good night’s sleep. Leptin levels typically rise during sleep.

You can also take supplements to remove toxins from the body and protect your leptin regulators!

Brain School: Eaton Arrowsmith | Learning Disabilities | Brain Training

Monday, February 21st, 2011

Brain School Eaton Arrowsmith
Howard Eaton, co-founder of the Eaton Arrowsmith Schools, has published a book about his work with Barbara Arrowsmith. Eaton and Arrowsmith pioneered the use of brain training to induce neuroplasticity in the brains of children with learning disabilities, rewiring their brains to function better.

Eaton Arrowsmith’s premise that we needn’t feel constrained by the brain we have but can train our brains to work more effectively is fundamental to MindSparke’s approach to brain training.

Eaton wrote the book to raise awareness about the advantages of using brain training for children with learning disabilities and attention disorders. “My hope is that Brain School will ask politicians, educational administrators, psychologists, psychiatrists, family doctors, educators, parents, and others involved in education to be open to the idea that cognitive functioning can improve and the brain can change,” he said.

“Because there is a lack of knowledge and facts about neuroplasticity, there is a general trend in education to keep practicing the same instructional remediation methods for children with learning disabilities.”

Brain School: Stories of children with learning disabilities and attention disorders who changed their lives by improving their cognitive functioning
is available at,, and to retailers at

Neurogenesis And Humor: Tell Me Another

Wednesday, February 16th, 2011
neurogenesis humor

Do I Laugh Now?

A penguin and a Gelotologist walk into a comedy club. “I know why he’s here,” says the waitress, gesturing to the Gelotologist, “But what are you doing here?”

“It’s cold outside,” says the penguin.

If you think neurogenesis is funny, you may well be right. Recent research that delves into the brain’s response to humor (and other good stimuli) could yield new therapies for improving mental health and relieving depression and anxiety.

Unlike penguins, who don’t usually frequent comedy clubs (unless it’s cold outside,) Gelotologists study the physiological and psychological effects of humor. They know that it’s good for us, but unfortunately we seem to be predisposed to pay more attention to negative stimuli than positive stimuli. We care far more if we lose $100 than if we win $100, for instance.

This outcome is called the “negativity bias.” Loss or misfortune activates our fight-or-flight response, causing us to experience negative events more intensely, which in turn signals our brain to remember them more clearly. This negativity bias creates a hurdle for the Gelotologists.

Add to this the fact that some people are naturally more negative, leading them to worry about negative events and become even more vigilant and anxious. This vicious cycle can lead to depression and chronic anxiety. So how do we interrupt this negative feedback loop?

The negativity bias is typically a subconscious response, so the first step in countering it is to realize it exists. Psychologists then suggest re-framing or reinterpreting our experiences. If we can cast what seems to be a bad or worrying situation in a positive or humorous light, we take a step toward counteracting its adverse psychological impact. We can use neurogenesis to our advantage. Through conscious effort and the powers of neuroplasticity, we can use humor to redirect our thoughts more positively.

The second aspect of successful plastic brain change is repetition. To encourage neurogenesis and plastic change we must practice, and practice often, adopting a more positive outlook on apparently negative experiences.

While at first, the intentionally positive reactions may feel forced, unnatural and even quite difficult, over time, they will become second nature — a happier nature.

More laughter on the brain

Brain Training, Neurogenesis, & Meditation

Wednesday, February 9th, 2011

Brain Training and Meditation

brain training online meditation

Brain Training And Meditation

So often different medical, scientific and philosophical disciplines travel on parallel paths, unaware or only dimly aware of one another’s existence. This applies to many spheres, not just brain training, neuroscience, medicine, and psychology. But when these parallel paths bend slightly and converge, exciting progress often results.

Scientists from the Harvard Medical School, the Massachusetts Medical School, and the Bender Institute of Neuroimaging recently bent their paths to study the impact of mindfulness (regular meditation) on the brain. And here at MindSparke we find our own path of brain training research bending to meet them.

The research team set out to investigate what if anything was changing in the brain as a result of mindfulness practice. Specifically, they used neuroimaging to look for “pre–post changes in brain gray matter concentration” of sixteen healthy, meditation-naïve participants who took part in the two month program. The team looked for changes in gray matter concentration compared with a control group of 17 individuals. They found increases in gray matter concentration in the left hippocampus — the posterior cingulate cortex, the temporo-parietal junction, and the cerebellum in the MBSR group compared with the controls. In other words, brain regions involved in learning and memory processes, emotion regulation, self-referential processing, and perspective taking.

Brain Training Online with Brain Fitness Pro SE – Meditation Included!

From a brain training perspective this is phenomenal. At MindSparke we’ve been investigating the brain training benefits of meditation before training with Brain Fitness Pro. We’ve found that just a brief (eight minute or so) period of mindful meditation before brain training with Brain Fitness Pro’s working memory exercises increases the effectiveness of the dual n-back training by as much as 20%. Several months ago we incorporated guided meditation into the MindSparke Brain Fitness Pro SE (Special Edition) online brain training program.

Neuroplasticity, Self, And Free Will

Friday, December 17th, 2010

In a great post from the blog “Meaning And Truth” Sarah B discusses neuroplasticity, the concept of self, and free will. All subjects of great interest to me, too.

Read Sarah’s Post

Calling All Hamsters: Hold That Flight

Wednesday, December 15th, 2010

Paris Here We Come

Simulating the effects of jet lag by disrupting hamsters’ sleep patterns, researchers from the University of California, Berkeley, showed that “jet lag” made the hamsters dumber. (And as far as I know hamsters aren’t renowned for their smarts.)

Already linked to higher rates of cardiovascular disease, diabetes and cancer, odd sleep patterns like those of frequent long haul travelers would now seem to be bad for the brain, too.

Study coauthor Erin Gibson likened the hamsters’ sleep regime to “a flight from New York to Paris every three days.” Her study found a 50% decrease in neurogenesis in the hippocampus, and diminished ability to adapt to a new environment. The learning and memory problems persisted for more than four weeks after a return to a normal sleep schedule.

There’s no clear answer yet about why this happens, but it’s useful to know — even if we can’t avoid long distance travel, we can still try to make sure that we get regular, sufficient sleep… (So says the father of a four-month old, a two-year old, a six-year old and a teenage daughter.)

Coping And Brain Growth

Wednesday, November 17th, 2010
stress coping and neurogenesis

(Not The Actual) Squirrel Monkeys

While we may not particularly like the process, it seems that coping with stress leads to neurogenesis. Professor David Lyons (Stanford) and his team examined the impact of social stress in primates. They found increased brain cell growth in the hippocampus when the animals successfully reorganized their social ties after a separation.

The team tested their premise, that coping tends to counteract the otherwise negative effects of stress, by intermittently separating pairs within a group of adult male squirrel monkeys and allowing new pairs to form.

They found increased hippocampal neurogenesis in the squirrel monkey males. Previous studies with rodents found that hippocampal neurogenesis contributes to spatial learning performance, and Lyons’s team found enhanced spatial learning in the monkeys, too.

The conclusion for us? Therapies designed to promote stress coping potentially have similar effects in humans, particularly those suffering from depression.

Here then we have another reason why Brain Fitness Pro can help alleviate depression.

Touch Promotes Brain Growth

Tuesday, November 16th, 2010

Wikimedia commons: Aaron Logan

Scientists from the Weizmann Institute of Science have discovered that novel and diverse tactile stimulation results in a remarkable boost to the production of new brain cells in young mice.

“We had not expected to have such an amazing effect,” said Ravid Shechter, who helped execute the experiments. “It was a very fast response to the environment.”

As reported today in The New Scientist, neuroimmunologist Michal Schwartz and his team placed mice in cages with a variety of unfamiliar flooring materials, such as small rocks, sandpaper, or sponge, or a combination. Just 2 hours later the team measured a dramatic increase in the number of new cells in the dorsal horn. Mice in cages with mixed flooring materials grew more cells, indicating that a diverse environment amplified the effects of new tactile sensations.

The team went on to test the impact of repeated and prolonged exposure to the new environments. They found no further increase in neurogenesis, and perhaps even a slight decrease, but the new brain cells produced after initial exposure did differentiate and lead to the production of so-called “GABAergic” cells — inhibitors.

Schwartz pointed out that these GABA cells likely played a role in the mice becoming accustomed to the new sensations. Commenting on the findings neuroscientist Pierre-Marie Lledo from the Pasteur Institute noted that the process displayed a remarkable similarity to the production of new brain cells in the region responsible for processing smells in adult mice.

Schwartz’s work may have implications for pain management and treatment, Lledo suggested. The new GABAergic neurons appear where pain fibers terminate in the spinal cord, “more newborn neurons located here will provide more inhibition to these nocioceptive fibers, and therefore will change the threshold of pain.”

Commenting on alternative “touch treatments”, Schwartz said, “In this regard, [our results] may give a scientific basis to unexplained effects of touch treatment.”

New Brain Cells, Stress, And Learned Behavior

Thursday, April 1st, 2010
Stressed Out Mouse

Stressed Out Mouse

A new study by UT Southwestern scientists (Lagace, Donovan, DeCarolis, Farnbauch, Malhotra, Berton, Nestler, Krishnan and Eisch) sheds some light on the connection between stress and neurogenesis.

Eisch and her colleagues performed two experiments related to stress.

1. They exposed mice to a socially stressful experience — confrontation with a more aggressive mouse (the mouse equivalent of a carjacking), then measured the immediate and long term impact on the generation of new brain cells.

2. They irradiated mice to eliminate neurogenesis before exposing the irradiated mice to the same kind of stressful situation.

The scientists made two important findings:

In the first experiment, the stressful situation reduced neurogenesis temporarily (for a few days), and left the mice more likely to be fearful in similar situations.

In the second experiment the irradiated mice showed less fear when exposed to similar stressful situations.

These findings indicate that neurogenesis is key to forming stress memories. This can be a healthy response, educating us on avoidance. (Common sense.) But in cases of inappropriate or chronic stress response, neurogenesis may be overactive.