Brain Waves Create Archives of Experience and Expectation
Neuroscientists can now map a ‘memory trail’ based on brain wave patterns.
Posted Jun 26, 2013
Neuroscientists are now able to trace specific patterns of life experience and learning by mapping specific patterns of brain waves. The ability to take a snapshot of individual brain wave patterns via functional magnetic resonance imaging (fMRI) gives scientists a tool to map each individual’s experience as a unique life tapestry. This could lead to finely tuned methods for objective diagnosis and for treatments of neuro-psychological diseases.
Research released on June 25, 2013 from the Weizmann Institute shows that spontaneous waves of neuronal activity in the brain leave visible imprints of earlier events for at least 24-hours after the experience has taken place.
The Weizmann study, published in the current Journal of Neuroscience, shows that the activation of specific areas in the cortex visibly remodeled brain wave patterns even when the brain was ‘at rest.’ The new research stems from earlier findings in the lab of Professor Rafi Malach of the Institute's Neurobiology Department, and others, that the brain actually never rests.
Even when you are resting with your eyes closed—and there is no visual stimulus entering your brain—the normal bursts of nerve cell activity are replaced by ultra-slow patterns of neuronal activity. These ultra-slow patterns reveal traceable patterns of brain activity based on experiences you have had in the past 24-hours and earlier. Interestingly, the new patterns not only remained the next day, they were significantly strengthened after a night's sleep.
These spontaneous or "resting" waves travel in a highly organized and reproducible manner through the brain's outer layer called the cortex. The patterns that brain waves create are complex. They are also periodic and symmetrical. Like hieroglyphics, these patterns seem to tell a story and have specific meaning. Researchers at Rafi Malach's lab set out to uncover their significance with a hypothesis that the patterns of resting brain waves may constitute "archives" of earlier experiences.
In the experiment, the researchers had volunteers perform a training exercise that activated a specific network of nerve cells in the frontal lobes. While undergoing brain scans in a fMRI, the subjects were asked to imagine a situation in which they had to make rapid decisions. The subjects received auditory feedback in real time, based on the information obtained directly from their frontal lobe, which indicated the level of neuronal activity in the trained network.
This "neurofeedback" strategy proved highly successful in activating the neural network of the frontal lobes. To test whether the brain connections created during this exercise would leave their traces in the patterns formed by the resting brain waves, the researchers performed fMRI scans on the resting subjects before the exercise, immediately afterward, and 24-hours later.
The fMRI images of the resting brain waves showed that brain areas that were wired together during the training sessions exhibited an increase in their functional link a day after the training. Conversely, those areas that were deactivated by the training showed a weakened functional connectivity.
Experience Influences Future Behavior at a Neuronal Level
A previous University of California, San Francisco (UCSF) study from 2012 found that patterns of brain activity in the rat brain play a role in the formation and recall of memories and decision-making. The UCSF researchers showed that the brain patterns of rats display rapid replays of past experiences and are fundamental to their ability to make decisions. Disrupting the particular brain patterns linked to past experience impaired the animals' ability to learn rules based on memories of things that had happened in the past. The same is true in humans.
"We think these memory-replay events are central to understanding how the brain retrieves past experiences and uses them to make decisions," said neuroscientist Loren Frank, PhD, an associate professor of physiology and a member of the Keck Center for Integrative Neuroscience at UCSF. Through these brain waves, the rat reprocesses and replays old experiences in a fleeting instant. The lessons from the past are essential for shaping their perception of the present.
"We think these memory replay events are a fundamental constituent of memory retrieval and play a key role in human perspective and decision-making as well," Frank said. "These same events have been seen in memory tasks in humans, and now we know they are critical for memory in rats. We think that these fast-forward replays make up the individual elements of our own memories, which jump rapidly from event to event."
Neuroplasticity Reminds Us That Mindset Is Never Fixed
Neuroplasticity is nothing new. Donald O. Hebb began studying neuroplasticity in the mid-20th century. In fact, his popular studies on “Hebbian Plasticity” and “Hebbian Learning” from the 1950s were founded on the principles that the brain is 'plastic' and is constantly reshaping itself. I wrote extensively about the power of neuroplasticity in The Athlete's Way. (St. Martin's Press)
Donald Hebb discovered that neurons ‘fire-and-wire’ together through repeated patterns of experience, thinking, and behavior. The current neuroscientific findings support classic learning principles proposed by Donald Hebb, who discovered that the co-activation of two linked nerve cells leads to long term strengthening of their link, while activity that is not coordinated weakens this link.
The weakening of a neural network is called neural darwinism. Just like you can fire-and-wire neurons together through conscious training, you can also prune these connections by consciously denying to engage or nourish them. Each of us can literally hardwire brain patterns and the ‘trails’ that our mind is inclined to travel. You can incinerate negativity and nourish positivity by the choices of behavior and mindfulness you make everyday.
You can choose to see the glass as half-full or half-empty. Over time, these explanatory styles become hardwired habits at a neural level. Neuroplasticity is in the locus of your control. You can use these principles to change patterns of thought and behavior. Rewiring your mind can help you cope with and dismantle stressful memories, remove negativity and lower anxiety from your daily life. These changes could be seen in an fMRI reflected by changes in the neural networks and brain waves of your mind.
As our experiences become embedded in neural networks connections, they create "expectations" that come into play before we perform any type of mental task. This enables us to anticipate a consequence or outcome. The researchers hypothesize that information about earlier experiences is incorporated into the links between networks of nerve cells in the cortex, and these show up in the brain's spontaneously emerging wave patterns, even when we are at rest.
Conclusion: Mind Creates Reality
This new research suggests a wide range of future possibilities for exploring the mind and brain. For example, studying brain wave patterns could be used as a "mapping tool" for uncovering cognitive events from an individual's recent past and taking a snapshot of these cognitive states as a type of "brainprint." Researchers believe that a person's unique brain activity patterns could reveal a personality profile that is like a fingerprint – highlighting each individual's abilities, shortcomings, biases, learning skills, etc.
"Today, we are discovering more and more of the common principles of brain activity, but we have not been able to account for the differences between individuals," says Rafi Malach. Adding, "In the future, spontaneous brain patterns could be the key to obtaining unbiased individual profiles. Such profiles could be especially useful in diagnosing or learning the brain pathologies associated with a wide array of cognitive disabilities.”
These findings give neuroscientists a new way to research processes like learning and decision-making in animals and in people. It also may help shed light on memory disorders like post-traumatic stress disorder (PTSD), which is characterized by strong, disturbing and uncontrolled memories. More research needs to be done on how replay events impact the way we make decisions. By finding ways to amplify or block specific replay events we can change the way we learn and remember.
Our habits of thought lead to habits of behavior at a neuronal level. Hopefully, these findings will inspire you to be proactive in reshaping the neural networks of your mind and re-wire your brain towards more loving-kindness, optimism and a positive explanatory style.