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Saturday
Nov232013

Why Willpower Fails You And What To Do About It

Thursday
Nov142013

How Exercise Makes Your Brain Grow

David DiSalvo's newest book, Brain Changer, is now available at AmazonBarnes and Noble and other major booksellers. 

 

Research into “neurogenesis”—the ability of certain brain areas to grow new brain cells—has recently taken an exciting turn. Not only has research discovered that we can foster new brain cell growth through exercise, but it may eventually be possible to “bottle” that benefit in prescription medication.

The hippocampus, a brain area closely linked to learning and memory, is especially receptive to new neuron growth in response to endurance exercise. Exactly how and why this happens wasn’t well understood until recently. Research has discovered that exercise stimulates the production of a protein called FNDC5 that is released into the bloodstream while we’re breaking a sweat. Over time, FNDC5 stimulates the production of another protein in the brain called Brain Derived Neurotrophic Factor (BDNF), which in turns stimulates the growth of new nerves and synapses – the connection points between nerves – and also preserves the survival of existing brain cells.

What this boils down to in practice is that regular endurance exercise, like jogging, strengthens and grows your brain. In particular, your memory and ability to learn get a boost from hitting the pavement.  Along with the other well-established benefits of endurance exercise, such as improved heart health, this is a pretty good reason to get moving. If jogging isn’t your thing, there’s a multitude of other ways to trigger the endurance effect – even brisk walking on a regular basis yields brain benefits.

Now researchers from the Dana-Farber Cancer Institute at Harvard Medical School (HMS) have also discovered that it may be possible to capture these benefits in a pill.  The same protein that stimulates brain growth via exercise could potentially be bottled and given to patients experiencing cognitive decline, including those in the beginning stages of Alzheimer’s and Parkinson’s.

"What is exciting is that a natural substance can be given in the bloodstream that can mimic some of the effects of endurance exercise on the brain," said Bruce Spiegelman, PhD, of Dana-Farber and HMS and co-senior author of the research report with Michael E. Greenberg, PhD, chair of neurobiology at HMS.

In the new study, the research team artificially increased BDNF in the brains of mice by using a harmless virus to piggyback FNDC5 molecules through the bloodstream of the mice.  After seven days, researchers found a significant increase in BDNF in the hippocampus area of the mice brains – the brain area crucial for memory and learning.

"Perhaps the most exciting result overall is that peripheral delivery of FNDC5 with adenoviral vectors (i.e. a virus) is sufficient to induce central expression of BDNF and other genes with potential neuroprotective functions or those involved in learning and memory," the authors said.

The research team cautions that since this is an animal study, it’s far too early to conclude that the same effect will work in humans, but the significant results of this study show promise for future research into delivering cognitive benefits to the human brain via a similar mechanism. Cognitive boost for suffers of Alzheimer’s, Parkinson’s and other debilitating diseases in the form of a brain-growth pill may not be too far off.

More immediately, neurogenesis research has provided yet another great reason to get up, get out and get moving.

The research report was published in the journal Cell Metabolism.

You can find David DiSalvo on Twitter @neuronarrative.

Wednesday
Nov062013

How Neuroscience Could Make Your Resistance Futile

David DiSalvo's newest book, Brain Changer, is now available at AmazonBarnes and Noble and other major booksellers.

 

Comply. That’s an uneasy watchword at the very center of social cohesion. Without enough social norm compliance—such as the norm that stresses fairness in our dealings with others—humans aren’t great at getting along. The question is, what’s at the heart of our willingness to comply with social norms?  Are our brains pre-packaged with compliance wiring? Or do we bend to the dictates of fairness and equal treatment only because our laws press us into compliance? Or is it some of both?

Neuroscientists are quite interested in these questions, and they’ve even made some progress answering them. Studies using functional magnetic resonance imaging (fMRI) have identified brain areas that appear to be involved in our decisions about when and why we treat others fairly or unfairly. These studies have shown, for example, that a region in the right hemisphere of the brain called the right lateral prefrontal cortex (rLPFC) is activated when people comply with social norms (or "rules"), suggesting that the rLPFC is an important part of a neural network that could be considered our brain’s social-norm wiring. But as with all fMRI results, brain activity does not conclusively prove a causal relationship between a given brain area and a given behavior—the results can only suggest it.

new study from researchers at the University of Zurich took all of this a big step forward by using a painless and harmless electrical charge to positively or negatively stimulate the rLPFC  (something called “transcranial direct current stimulation”) while study participants took part in a computerized fairness game.

The game works like this: participants are given an amount of money and told to share it with a randomly assigned partner. In one game scenario, they are allowed to make the decision of how much money to give away without the threat of a penalty for being unfair.  In another scenario, they are told they can still make the decision, but their partner will be able to penalize them if they act unfairly.

In the first phase of the study, participants played the fairness game without experiencing the electrical charge. The social norm of fairness dictates that people give away an equal or near equal portion of the money, but without the threat of a penalty most participants only gave away between 10-25% of their stash. With the threat of a penalty, the percentage increased to between 40-50%.

Researchers then had the participants play the game again, but this time while experiencing a positive electrical charge designed to increase activity in the rLPFC.  Participants receiving the positive charge increased the amount of money they gave away by about 33%. When researchers switched to a negative charge (which decreased rLPFC activity), participants decreased the amount they gave away by about 22%.

But here’s the twist: these results only held true when a penalty was threatened. Without threat of a penalty, the positive and negative charges to the rLPFC actually had an opposite effect.  Researchers also checked to see if the electrical charges changed the participants’ expectation of how strong or weak the penalty would be, and found no change in threat expectation.

What this means is that stimulating the brain region didn’t make people fairer -- it made them more sensitive to threats of being punished if they didn’t act fairly.

The implications of this finding are potentially massive, and more than a little alarming. If we can biochemically alter activity in the rLPFC with a pill, just as these researchers did with an electrical current, then we’re looking toward a brave new pharmacological world that serves up a daily dose of compliance via threat sensitivity (assuming, of course, that there might be a market for such a drug). On a more positive note, the finding opens a door to treat people with damage to their rLPFC, who may be dangerously non-compliant with social norms.

However you choose to view the results, the research is significant because it bridges a chasm between seeing brain activity in relation to a behavior (in an fMRI brain scan) and changing behavior by manipulating brain activity. And while that's also a little frightening, it's a necessary step toward figuring out where ambiguous concepts like "social norm compliance" play out in the brain. This study is just a tiny taste of what's to come.

Saturday
Oct262013

10 Things You Should Know About Goals

David DiSalvo's newest book, Brain Changer, is now available for pre-order on Amazon and Barnes and Noble. It will hit store shelves on November 12.

 

Setting and reaching goals is a mainstay topic in research across a range of disciplines, including psychology, neuroscience, marketing, and communications. Below is a survey of 10 recent findings about goals, chosen from these and other topic areas, that throw some light on the ups and downs of goal achievement.

1. Giving up a goal takes a psychological and physical toll.

First a word of caution – goal achievement is risky business. If setbacks start accumulating, and you begin doubting whether you can reach your goal, you’re on your way to what psychologists call an “action crisis.” This is the crucial point at which you experience an internal conflict about whether you should keep going or give up. Research has shown that experiencing an action crisis increases production of the stress hormone cortisol, which is your brain’s way of sounding a body-wide alarm in response to the internal conflict. The problem is, the extra cortisol doesn’t help your performance, and may contribute to giving up sooner. It also increases blood pressure, which takes a toll on your blood vessels.

2. Being more specific can help you reach your goal.

We like flexibility in our lives, but some recent research (PDF) from consumer psychology suggests that being more specific and less flexible may be more effective in goal achievement.  The premise is simple but not easily accepted: specific steps, accomplished in strict order, seem harder to do at first, but ultimately lead to greater goal achievement than an ambiguous plan.  The problem is that more ambiguous, flexible plans seem much more appealing upfront.

3. Our brains may have an internal guidance system for reaching goals.

Research from neuroscience suggests that our brains use the neurotransmitter dopamine as an internal guidance system to reach goals. An animal study showed that the dopamine signal in the brain gets stronger as the goal gets closer. It’s sort of a “Marco Polo” effect that influences choices made to direct action toward a goal, and adjusts expectations about how close or far away the goal really is.

4. Your inner voice is a potent goal-achievement tool.

Reacting impulsively can thwart goal achievement, and research shows that your inner voice is an effective way to control impulses. A study suggests that simple things like telling yourself “Keep going, you can do it” while you’re exercising really does help keep you moving, and sidetracks the impulse to give up because the activity is getting harder.

5. Fist power could keep you from choking.

study earlier this year showed that clenching your left (but not right) fist can prevent you from choking under high pressure situations, as you might experience on your way to achieving a physical performance goal. The effect was studied across three experiments with athletes as test subjects, and the results were consistently significant. The researchers believe that left fist clenching primes the right hemisphere of the brain, aiding automatic skill performance (the opposite of conscious deliberation, which is thought to be controlled in the left hemisphere and actually contributes to choking).

6. Sharing your goals with friends improves your chances of reaching them.

More research from this year indicates that writing down your goals, sharing them with friends, and sending your friends regular updates about your progress can boost your chances of succeeding. The study showed that people who merely thought about their goals and how to reach them succeeded less than 50% of the time, while people who wrote goals down, and enlisted friends to help them by sending regular progress reports succeeded closer to 75% of the time.

7. Overmotivation can undermine goal achievement.

Motivation is essential to goal achievement, but overmotivation can lead to exactly the opposite. When your brain is in a hyper state of arousal about wanting something, the neurotransmitter dopamine floods your brain’s reward circuits. Research shows that when this happens, your chances of failing increase no matter how hard you try. Mental focus and precision are deluged by the flood.  The trick seems to be to find the happy motivation balance that keeps you moving forward without tripping on your brain’s in-built foibles.
 

8. And so can fantasizing.

Even though it’s tempting, research suggests that fantasizing too much about your dream job or any other major goal can undermine success. It's all about expectations. Realistic thinking fosters more realistic expectations; fantasizing blows expectations out of proportion, obscuring vision of what must actually be done to reach a goal.

9. And so can overthinking.

Although an incredibly powerful organ, the brain can get in its own way (in many ways) – and, ironically, thinking too much is one of them.  A study indicated that there’s an interesting connection between memory and performance. Once the right skills for a given task are internalized (like the many parts of a perfect golf swing), thinking about them when trying to perform doesn’t help, it hurts.

10. Finally, try to stay optimistic.

While easier said than done, keeping an optimistic mindset appears to enable people to deal with stress more effectively -- a key to goal achievement. Looking on the bright side actually is good for you, and an effective way to help reach your goals.

David DiSalvo's newest book, Brain Changer, is now available for pre-order on Amazon and Barnes and Noble. It will hit store shelves on November 12.

Saturday
Oct192013

The Big Stink About Anxiety: It Changes How Our Brains Process Odors 

Anxiety causes a slew of unpleasant symptoms that all of us have experienced to greater or lesser degrees. Sweating, rapid heartbeat, churning stomach, and fear – these are just a few symptoms of an anxious mind. One lesser known symptom is that when we’re anxious, things don't smell quite right.

A new study explored this odd effect by focusing on the role of stress in rewiring the brain.  Two brain circuits that don’t typically “talk” to each other—one linked to our sense of smell and another linked to emotional processing—can become cross-wired when we experience stress-induced anxiety. The result is that stressful experiences transform normally neutral odors into bad ones.

Researchers first asked a group of subjects to rate several smells, all of which were  inoffensive neutral odors.  The subjects were then hooked up to a functional magnetic resonance imaging machine (fMRI) while they watched a series of  disturbing images, like car crashes and graphic war scenes, accompanied by equally disturbing text messages.

After the fMRI, the subjects were exposed to the same set of smells and asked to rate them again. This time, the majority of subjects changed their rating of the smells from neutral to offensive.

"After anxiety induction, neutral smells become clearly negative," explains Wen Li, a professor of psychology at the University of Wisconsin-Madison Waisman Center, who led the study. "People experiencing an increase in anxiety show a decrease in the perceived pleasantness of odors. It becomes more negative as anxiety increases."

The fMRI brain scan—which allowed the researchers to watch what was happening in the subjects’ brains in real time—suggests that stress-induced anxiety from watching the disturbing images and reading the messages triggered a cross-wiring between the smell and emotion brain circuits.

"In typical odor processing, it is usually just the olfactory system that gets activated," says Li. "But when a person becomes anxious, the emotional system becomes part of the olfactory processing stream."

The researchers think that this effect accumulates over time.  The more anxiety we experience, the more the cross-wiring between these two brain circuits strengthens – resulting in more and more otherwise neutral smells turning into bad ones.  The vicious cycle triggered by this effect is that the smells themselves contribute to more anxiety.

According to Li, "We encounter anxiety and as a result we experience the world more negatively. The environment smells bad in the context of anxiety. It can become a vicious cycle, making one more susceptible to a clinical state of anxiety as the effects accumulate. It can potentially lead to a higher level of emotional disturbances with rising ambient sensory stress."

This isn’t the first study, by far, to examine the link between emotions and sense of smell. Journals are full of research explaining why, for example, we think of the holiday season when we smell pine cones, or remember family gatherings when we smell cookies baking.  But it is one of the first to explore the specific role of anxiety in causing a bridge between these brain circuits, and that understanding may help psychologists untangle the bundle of anxiety triggers in people diagnosed with anxiety disorders.

The study was published in the Journal of Neuroscience.

David DiSalvo's newest book, Brain Changer, is now available for pre-order on Amazon and Barnes and Noble. It will hit store shelves on November 12.