Brain Facts:
Brain Exercise

Decline

If you stop learning, and that includes any subject that interest you, your overall mental capacity and performance will decline. That’s because of the weakening and eventual loss of brain networks. Such brain alterations don’t take place overnight, of course. But over a varying period of time, depending on your previous training and natural abilities, you’ll notice a gradual but steady decrease in your powers if you don’t nourish and enhance these networks.

Mental Hygiene

Mental Hygiene describes the measures a person can take to make the brain function more efficient. Just as the body benefits from exercise, good diet, and a temperate lifestyle, the brain works better if a person follows certain mental guidelines. The most import guideline involves not paying too much attention to our feelings.

Multitasking: The Brain Seeks Novelty

The brain is built to ignore the old and focus on the new. Marketers clearly understand this: If you watch closely, you will notice that heavily-played television ads will change ever so slightly after being on the air for a few weeks. When this change is detected by the brain, our attention is drawn to the ad, oftentimes without us even realizing it. Novelty is probably one of the most powerful signals to determine what we pay attention to in the world. This makes a lot of sense from an evolutionary standpoint, since we don't want to spend all of our time and energy noticing the many things around us that don't change from day to day.

Researchers have found that novelty causes a number of brain systems to become activated, and foremost among these is the dopamine system. This system, which lives deep in the brain stem, sends the neurotransmitter dopamine to locations across the brain. Many people incorrectly think of dopamine as the "feel-good" neurotransmitter because drugs that create euphoria, such as cocaine and methamphetamine, cause an increase of dopamine in particular parts of the brain. However, a growing body of research shows that dopamine is more like the "gimme more" neurotransmitter.

Another interesting fact about dopamine is that nearly every drug that people abuse has an effect on the dopamine system (as do chocolate, money, sex, and many other addictive things).
Again, the role of dopamine is not in the pleasure that one may get from the drug, but in establishing the craving that keeps one coming back for more, even after the drug has lost its pleasurable effects.

A final important fact about dopamine is that it is very much involved in learning and memory.

Learning and memory occur in the brain through changes in the way that neurons connect to one another. We know that the brain is very "plastic," meaning that it can change drastically with experience. However, the brain needs some way to control these changes; after all, we wouldn't want our entire visual system to be rewired to see upside down after doing a single handstand. Dopamine is one of the neurotransmitters that control this: When dopamine is released, it is a signal to the brain that is it now time to start learning what is going on.

Exposure to new experiences improves memory, according to research by UCL psychologists and medical doctors that could hold major implications for the treatment of memory problems. The study, published in ‘Neuron’ on 3 August, concludes that introducing completely new facts when learning, significantly improves memory performance.

A region in the midbrain (substantia nigra/ ventral tegmental), which is responsible for regulating our motivation and reward-processing, responds better to novelty than to the familiar. This system also regulates levels of dopamine, a neurotransmitter in the brain, and could aid learning. This link between memory, novelty, motivation and reward could help patients with memory problems.

Dr Emrah Düzel, UCL Institute of Cognitive Neuroscience, said: “We hope that these findings will have an impact on behavioral treatments for patients with poor memory. Current practice by behavioral psychologists aims to improve memory through repeatedly exposing a person to information – just as we do when we revise for an exam. This study shows that revising is more effective if you mix new facts in with the old. You actually learn better, even though your brain is also tied up with new information.

“It is a well-known fact amongst scientists that the midbrain region regulates our levels of motivation and our ability to predict rewards by releasing dopamine in the frontal and temporal regions of the brain. We have now shown that novelty activates this brain area. We believe that experiencing novelty might, in itself, have an impact on our dopamine levels. Our next project will be to test the role of dopamine in learning. These findings could have implications for drug development.”

Separate behavioral experiments were also conducted without the use of a scanner to test the subjects’ memory. Their memory of the novel, familiar and very familiar images they had studied was tested after 20 minutes and then a day later. Subjects performed best in these tests when new information was combined with familiar information during learning. After a 20 minute delay, subjects’ memory for slightly familiar information was boosted by 19 per cent if it had been mixed with new facts during learning sessions.

Dr Düzel said: “When we see something new, we see it has a potential for rewarding us in some way. This potential that lies in new things motivates us to explore our environment for rewards. The brain learns that the stimulus, once familiar, has no reward associated with it and so it loses its potential. For this reason, only completely new objects activate the midbrain area and increase our levels of dopamine.”

Neurobiologists have known that a novel environment sparks exploration and learning, but very little is known about whether the brain really prefers novelty as such. Rather, the major "novelty center" of the brain--called the substantia nigra/ventral tegmental area (SN/VTA)--might be activated by the unexpectedness of a stimulus, the emotional arousal it causes, or the need to respond behaviorally. The SN/VTA exerts a major influence on learning because it is functionally linked to both the hippocampus, which is the brain's learning center, and the amygdala, the center for processing emotional information.

Now, researchers Nico Bunzeck and Emrah Düzel report studies with humans showing that the SN/VTA does respond to novelty as such and this novelty motivates the brain to explore, seeking a reward. The researchers of University College London and Otto von Guericke University reported their findings in the August 3, 2006, issue of Neuron, published by Cell Press.

In their experiments, Bunzeck and Düzel used what is known as an "oddball" experimental paradigm to study how novel images activate the SN/VTA of volunteer subjects' brains. In this method--as the subject's brains were scanned using functional magnetic resonance imaging--they were shown a series of images of the same face or outdoor scene. However, the researchers randomly intermixed in this series four types of different, or "oddball," faces or scenes. One oddball was simply a different neutral image, one was a different image that required the researchers to press a button, one was an emotional image, and one was a distinctly novel image. In fMRI, harmless radio signals and magnetic fields are used to measure blood flow in brain regions, which reflects activity in those regions.

With this experimental design, the researchers could compare the subjects' response to the different kinds of oddball images to distinguish the brain's reaction to pure novelty itself from the other possible sources of brain activation, such as emotional arousal.
In a second set of oddball experiments, the researchers sought to determine whether the SN/VTA encodes the magnitude of novelty. In those experiments, the researchers measured activation of the region by images of different levels of familiarity or novelty. In yet other studies, the researchers assessed whether the subjects' memory of familiar images was better when presented along with novel images or very familiar images.

The researchers found that the SN/VTA does, indeed, respond to novelty, and these response scales according to how novel the image was. They concluded that their data provide evidence for "a functional hippocampal-SN/VTA loop" that is driven by novelty rather than other forms of stimulus salience such as emotional content or the need to respond to an image. The researchers said their finding that the SN/VTA is more activated by greater novelty is compatible with models of brain function "that see novelty as a motivating bonus to explore an environment in the search for reward rather than being a reward itself."

Also, Bunzeck and Düzel found that novelty enhanced learning in the subjects. "Thus, the human SN/VTA can code absolute stimulus novelty and might contribute to enhanced learning in the context of novelty," they concluded.

Finally, they said their findings raise the possibility that selective brain injury to the hippocampus could eliminate the positive effects of novelty in such patients and constitute one source of reduction in recognition memory in the patients.

The researchers include Nico Bunzeck of the University College London in London, United Kingdom; and Emrah Düzel of the University College London in London, United Kingdom and Otto von Guericke University in Magdeburg, Germany. This work was supported by a grant from the Deutsche Forschungsgemeinschaft (KFO 163, TP1).

Routines

If you become too wedded to routine, you’re turning off important brain areas and interfering with your brain’s optimal performance. But you can reverse this process by transforming routine activities into challenges. When you do, those important brain areas are recruited once again. This is important because these widely dispersed brain areas from a coherent system involving a great number of neuronal networks.

Jigsaw Puzzles