The power of brain plasticity

This article was contributed by Paul Li, who teaches cognitive science at UC Berkeley.

The human brain is quite remarkable. It does not remain static, but instead ceaselessly changes throughout life. Everything you learn or experience impacts the biology of your brain.

Though some cognitive abilities typically begin to decline in the third decade of life, cortical plasticity renews our hope that new connections can be willfully forged. For example, there was a little girl who was born with very little cortical tissue. Doctors did not see much of a future for her because she did not have a “normal” brain; however, because of cortical plasticity and the brain’s ability to reorganize itself, she learned to function quite well (Distelmaier et al., 2007).

The article highlighted that this “case teaches us that clinicians and parents should not give up in the face of an apparently hopeless case!”

In a previous post, Almost No Brain, a man managed to lead a normal life despite having minimal gray matter inside his skull. These two cases show how amazingly adaptable the brain is. The ability to shift the nature-nurture tension toward the nurture side is empowering for us, and provides hope even in the face of serious abnormalities of the brain.

References:
Distelmaier et al., “How Much Brain Is Really Necessary?” A Case of Complex Cerebral Malformation and Its Clinical Course, J Child Neurol 2007; 22; 756

Special thanks to Bradley Voytek, Helen Wills Neuroscience Institute, Berkeley, for his assistance.

Your Nervous System at Work

By Gregory Kellett, a cognitive neuroscience researcher at SFSU and UCSF, and science writer for Lumos Labs.

Ever wonder about the workings of your nervous system?  As mentioned in our previous post on cognition, the nervous system is responsible for integrating and processing information about your surroundings while directing action towards the achievement of goals; whether this be eating a tuna sandwich, serenading a lover or getting out of the way of a speeding bus. Physically, it is made up of your brain, spinal cord and peripheral nerves.

Let’s look at the structural components of this biological orchestra.

Neurons and Glia
The basic functional units of the nervous system include neurons (cells who’s primary job is to communicate) and glia (cells which support neurons and their communication).

The average brain has about 100 billion neurons and about 9 times as many glia.

Neurons (with the help of glia) connect and coordinate senses such as sight, hearing, smell, touch and taste with the activity of your muscles and organs. They are either taking information in for integration, communicating with other neurons for information processing, or sending information out to generate action.

Glial cells (of which there are multiple types) do a variety of tasks to support the functioning of neurons, including removing waste, providing nutritional and structural support and facilitating connections. Some glia have also been shown to communicate with neurons, as well as each other, in order to help coordinate neuronal activity.

Synapses and Neurotransmitters
Synapses are the actual locations at which neurons communicate with each other, and a typical neuron has about 10,000 of them.

Neurons communicate at synapses through the use of neurotransmitters. Neurotransmitters are chemicals sent between neurons as well as the muscles and organs they work with. They attach to receptors on receiving cells, translating into one of three basic types of messages:

•    Excitatory- Encouraging connected neurons and other related cells to “pass it on” or activate; perhaps prompting you to swat at that fly after being buzzed by the umpteenth time or dilate your pupils when the lights go out.

•    Inhibitory- Suggesting that the receiving cell not continue passing on the signal or take action. This could be involved in the shutting down of appetite in response to the non-acquired taste of anchovies or the ability to ignore the radio in your car while figuring out how to get un-lost.

• Adaptive- Instructing a neuron to change something in its structure or the way it functions. This is the basis of plasticity where neurons may reduce or increase the number of connections, move them around and or adjust their sensitivity; all of which are part of the learning process.

Neural Networks

Neurons which collaborate on a specific physiological function, such as hearing high pitches, moving your pinky or remembering to take the trash out, are considered to be part of a shared neural network. Typically these functionally related neurons will use only one or two of the over 100 different types of neurotransmitters available. Neurotransmitters, however, can and often are associated with several types of neural networks.

Serotonin is an example of a neurotransmitter involved with the regulation of multiple systems including mood, appetite, temperature, pain sensation and sleep.

Dopamine is the neurotransmitter of choice for neural networks dealing with reward, such as the feeling you get after winning an egg toss or eating a delicious meal. It is however also used by circuits involving memory and attention.

Complexity
As much as we do know about how our nervous systems work, there is still much more to be discovered. One of the many areas where little is known involves how different neural networks, responsible for such diverse tasks as detecting movement, recognizing objects and generating action, can communicate between themselves. The mechanisms involved in coordinating the information from different specialized neural systems into a seamless experience of say, catching a ball, is still a mystery.  This is referred to as the binding problem, and although there are plenty of theories, there are no clear answers as of yet.

As you can see, the interactions between our neurons, neurotransmitters and constantly shifting surroundings are complex…..especially when they are trying to grasp the complexity of interactions between neurons, neurotransmitters and constantly shifting surroundings;)

What is Cognition?

By Gregory Kellett, a cognitive neuroscience researcher at SFSU and UCSF, and science writer for Lumos Labs.

What exactly is cognition and how does it work? Here we will attempt to outline and explain some of the basic concepts involved with the inner workings of your head.

Cognition literally means “to know”.  Knowledge can be thought of as memories formed from the manipulation and assimilation of raw input , perceived via our senses of sight, hearing, taste, touch and smell.

Using knowledge to direct and adapt action towards goals is the foundation of the cognitive process. Past experiences and trends inform our sense of what the future might hold and help us to act accordingly.

Take a yearning for pizza for example… Cognition encompasses everything from knowing/remembering what pizza is (and that you like it)…to realizing that you are hungry and making plans to have it delivered.

In order for our finite minds to make sense of the near infinite details of our surroundings however,  a large part of cognition involves the organization of our thoughts into associations or categories. These might range from “things one might find in a kitchen” to “people I think are cute”. Simple symbols such as the word “face” are used to group more complex learned associations such as those between noses, lips, eyes and smiles.

Although important, these “cognitive categories” are overlapping and not always clearly distinct…so keep this in mind as we break down the concept of cognition itself into some of its more widely recognized pieces.

The words perception, attention, memory and executive function are one way of divvying up the processes involved in how we think. All of the above will be involved throughout your journey towards satisfying that pizza craving. Let’s use some specific points to illustrate their role in the overall process of attaining such a dinner goal.

Perception, in this case, of the fact that you feel hungry and that there is no food in the fridge, is what gets the whole process moving. It involves seeing, hearing, feeling, tasting and or smelling your surroundings, allowing you to respond appropriately.

Memory plays the obvious role of storing the name of your favorite pizza parlor. It also enables you to dial the number given by the operator and give directions to your house. Some different components include short term/working memory, long-term memory and subconscious/implicit knowledge.

Executive Function enables the planning of logistics, such as timing the pizza delivery to coincide with the arrival of your scrabble buddies.  Improvising (guessing what toppings everyone will enjoy), problem solving (figuring how much to tip) and controlling impulses (not ruining your appetite by eating a whole bag of Doritos while waiting) also come into play here.

Attention processes kick in by having you shift your focus from reading the Sunday funnies to answering the door upon hearing that long awaited knock. They also help in multi-tasking a slice of pizza with figuring out how to nail that triple word score all while ignoring the heckling antics of your so called “friends”.

Again, although separated for the purposes of our discussion here, it is the interplay of all of these systems working simultaneously which makes up the process of cognition; allowing us to adapt to our surroundings and take action towards obtaining our goals.

New Brain Game – Top Chimp!

We’re on a roll! Following the debut of Name Tag last month, we are now ready to release Top Chimp, a brain game that sharpens visual attention and trains working memory. We think it’s more fun than a barrel of…well, monkeys, but would love to have your feedback before the game becomes part of the regular set of brain exercises. Please find the game here http://games.lumosity.com/top_chimp.html and send any suggestions to games@lumosity.com.

Long-term and Working Memory – You Are What You Remember

By Gregory Kellett,  a cognitive neuroscience researcher at SFSU and UCSF and science writer for Lumos Labs.

Memories are vital to our ability to function on even the most basic of levels. Our respective “realities” are in fact a large part due to the constantly shifting kaleidoscope of our remembrances. Here we will touch briefly on the difference between short-term/working memory and long-term memory as well as how the two filter and add meaning to our worlds.

What if we could remember everything we experienced? As enticing as it sounds, our finite brains would quickly find themselves overwhelmed with the random details of yesterday’s weather forecast alongside the nutritional information off of last month’s box of raisin bran.

Thankfully, the vast majority of our memories are fleeting mental wisps lasting only seconds to minutes. These temporary impressions make up what is called short-term or working memory.

Working memory can be thought of as a staging area where the mind takes meaning from such items as:

• Specific immediate memories of very recent sensory input (IE the sour smell of expired milk).
• The temporary recollection of details from long-term memories (IE what happened the last time you drank sour milk).
• Conclusions and ideas made in the past (Sour milk is bad).

Notice how working memory can temporarily pull details from long-term memory for short-term use. Although constantly changing and ephemeral itself, working memory is vital to our ability to make decisions and take action over time (such as our pouring that sour milk down the drain). For a brilliant and more in-depth description of working memory read Elizabeth Buchen’s “Working Memory: What it is and how it works”.

When an experience or piece of information sticks and doesn’t evaporate with short-term memory, it is said to have entered into the realm of long-term memory. This journey is called consolidation and takes place after prolonged exposure to a piece of information or experience. The longer the exposure, the better the consolidation, the more robust the related memories will be.

Long-term memories can store much larger quantities of information than working memory and for much longer periods of time (often as much as a lifetime). These resilient long-term recollections are made up of both consciously learned facts, such as “Madrid is the capital of Spain” and subconsciously learned knowledge, such as the ability to balance and ride a bike.

We derive meaning and the ability to act via the synergistic relationship between long-term and working memory. Working memory combines elements from our long-term stores with immediate sensory information in order to generate ideas and plans of action. For example, remembering that the taste of peanut butter is pleasant as we toast toast, might just have us use our memorized skill of unscrewing a jar in order to manifest the pleasurable experience of peanut butter on toast. Which is just one more potentially delicious result of a fit and active mind.

Brain activity across languages

By Lumos Labs Science Associate, Paul Li, MS Neuroscience.

Different languages are represented differently across the brain. This is especially true for languages that are very dissimilar, such as English and Chinese. English is learned from pronouncing its 26-letter alphabet, whereas to learn the Chinese language, one needs to memorize thousands of characters in order to understand a string of pictographs.

Dyslexia, a learning disability that causes difficulty in reading and writing, affects the brain in different ways according to language. Professor Li-Hai Tan, along with his research team from the University of Hong Kong, discovered that Chinese-speaking dyslexics have a different pattern of brain activity than English-speaking dyslexics. Professor Tan told Lumos Labs that “the left middle frontal gyrus, rather than the posterior brain regions, is a perpetrator of reading disorders in Chinese, suggesting the possibility that a person who is dyslexic in Chinese reading would not be in alphabetic language reading, and vice versa.” One implication is that different interventions may be more or less suitable depending on language. 

Cognitive neuroscience research online

As I mentioned in Neuroscience Conference 2007, we recently presented evidence that the Lumosity application is not only an effective way to improve cognition, but it is also a useful platform for conducting basic research. The following is an abridged version of the “lay language summary” the Society for Neuroscience asked us to provide for the science press. The summary was co-authored by Lizzie Buchen, one of our science advisors.

Using the Web for Behavioral Research and Intervention: Evidence from Cognitive Training
We have found that a web-based application can be used to efficiently perform human behavioral intervention, and may provide a powerful platform for conducting large-scale human cognition experiments. In a test experiment, subjects who participated in a 30-day online cognitive training program, “Lumosity,” significantly improved in measures of memory and attention. Importantly, the web-based format allowed us to perform the intervention entirely over the internet, including subject recruitment, behavioral testing and training, and data collection and analysis.

After validating the efficacy of the training program and its feasibility as a research platform, we launched collaborations with other human behavior researchers interested in this novel form of intervention. Because the platform is substantially cheaper and less resource-intensive than non-web-based interventions, and its accessibility can improve subjects’ enjoyment and compliance, we found it in high demand among cognitive scientists. These experiments are currently in progress. (continued…)

Continue Reading »

Even YOU can get smarter

By contributing author Aimee Fountain, who splits her time between Lumos Labs and teaching at American River College.

According to an article published by Carol Dweck in the journal Educational Leadership, the type of praise students get is very much a factor in how they view their intelligence. And, how students view their intelligence is very much connected to their academic performance over time.

Students who were continually praised for being smart thought that intelligence was a fixed trait that they couldn’t do anything to affect, and which would manifest itself (or not) regardless of the effort put into a particular endeavor. Students who were praised for their efforts, on the other hand, associated their success with the amount of work they put in and, thus, concluded that their level of intelligence was malleable and dependent on their continued development and willingness to learn.

Students who believed that their intelligence was innate were inclined towards activities that would confirm or show-off their intelligence and avoided those activities which required effort. However, students who believed in the power of work to increase ability were much more likely to take on challenges and persist through them. The first group was also more likely to hide or lie about mistakes and deficiencies than the second group, which was inclined to correct them. Research in psychology and neuroscience supports this second group of students with evidence suggesting that the brain is really quite malleable and adaptive.

We get a lot of inquiries from people asking how their Lumosity scores stack up against the rest of the world (sound familiar? “How smart am I really?”). Thing is, when it comes to brain exercise, it doesn’t really matter how your score compares to others’. Instead, we hope that everyone plays to improve him/herself rather than to reconfirm or undermine his/her intelligence identity. A challenging curriculum should be viewed as an opportunity for growth and for developing new learning strategies.

Harness your growth potential! Intellectual development is not the natural unfolding of a finite amount of smarts!

Note added on November 29: For more on the topic of maximizing learning potential, see Scientific American’s December 2007 article The Secret to Raising Smart Kids.

See: Dweck, Carol S. Educational Leadership, October 2007 | Volume 65 | Number 2: Early Intervention at Every Age. ‘The Perils and Promises of Praise,” Pages 34-39.