The Plastic Brain

Written by Aiman Khan

Thumbnail Photo by Jesse Martini on Unsplash

Have you read a book recently? (fiction or nonfiction, doesn’t matter - and yes, your fifth-edition textbook on Canadian tort law counts!) Or maybe you played the latest Assassin’s Creed game now that Valhalla has officially been released? Or maybe you took the opportunity to learn a new skill during quarantine, like computer programming or French cuisine. Or maybe you have just finally fixed your sleep schedule and can now fall asleep without struggling to count sheep. Well, congratulations, you’ve helped your brain form new neural connections, and it’s now more neuroplastic as a result!

What is Neuroplasticity?

You might remember some of the basic makeup of our brains from AP Biology. Just like the well-designed interconnected road system of a sprawling metropolis, the neurons in our brains are interlinked and in constant communication with each other. Numbering in the billions, these cells – with the help of their support system in the form of glial cells – assist in the basic brain chemistry and electrical impulses that make up what you do, what you think, and in essence, who you are.

Neural activity underlies all of our thoughts and actions, whether it’s regulating your metabolic rate (how much energy you expend when you’re resting) or releasing the ‘love hormone’ oxytocin after a warm hug or compliment. The more a neuron fires, the more connected it grows to the surrounding nerve cells in its network. As Donald Hebb famously said, “neurons that fire together, wire together.” The more wired a neuron is to its surrounding nerve cells, the easier it is for us to carry out the actions associated with those neurons. For example, experienced typists can type with their eyes closed because the neural networks formed around this action have been strengthened by repeated firing which, in turn, is brought about by muscle memory. Unfortunately, this efficient system can sometimes work against us. For instance, such as in the case of undesirable habits like nail-biting, sugar-dependency, and more worryingly, addictions.

This is where neuroplasticity comes into play. Neuroplasticity happens when new pathways are forged between different neurons. Taking the analogy of a road system and neural networks a step farther, let’s imagine that you are new to Halifax and you live at the Park Victoria Apartments on South Park Street. Because it’s so close to home, you’ve always gone to Pete’s Fine Foods on Dresden Row for your groceries. In the three months you’ve lived in the city, you’ve only ever taken the route through Spring Garden Road to get there. However today, there’s a roadblock on Spring Garden, and the whole street has been sectioned off. You might give up and go home, or you might realize that there is another way to Pete’s – down Sackville Street near Citadel Hill.

This is basically how new neural pathways are formed in the brain. When you’re taking in new information – be it in the form of a new skill, passive reading, critical thinking, whatever it may be,. – electrical impulses in the brain go off the beaten path and travel to new and different neurons, firing off fresh connections. This is one reason why when we start new projects there is always a learning curve: our neurons are firing more than normal in order to establish a network. The implications of this are amazing-new neural connections in the brain. This means that we are able to form productive habits, learn brand new information, recover from debilitating diseases like strokes and paralysis, and overcome addictions.

Neuroplasticity in Adults

Up until the early 20th century, neuroscientists believed that our brains only grew during childhood. The general consensus at the time was that as children become adults, their brain plasticity decreases, and it is nearly impossible to learn new skills after the brain has developed past the age of 25.

One of the most famous studies on neurodevelopment was conducted by David Hubel and Torsten Wiesel on the critical window for development. Working with kittens whose eyes were sewn shut in order to achieve visual deprivation, they believed there was a short window of development early in life where the brain was especially sensitive to environmental input. Researchers theorized that if the brain didn’t receive the necessary stimuli within this short developmental time frame, the organism may not have been able to develop the associated functions later on. Notably, this sort of experiment would not be allowed in a modern lab as it flies in the face of ethics. However, we can still learn a lot from these early studies. This is why children are able to learn languages so much faster than adults. Early exposure to language plays a huge role in determining adult fluency, which was shown in the famous cases of Genie and Victor of Aveyron – children who were victims of abuse and neglect. As a consequence of the trauma they suffered, they both experienced significant delays in language acquisition later in life.

While there is no question that a child’s brain is far more neuroplastic than an adult’s, the opinion that neuroplasticity is exclusive to childhood started to change in the late 1900s when new evidence emerged of a continually adaptive brain. Most notably, Michael Merzenich – the ‘father of plasticity’ – argued against the critical window of development by demonstrating the regeneration of nerves. Later, more and more research into the visual system and topographical memory has shown that adult brain plasticity is not a phenomenon, but rather a common occurrence given certain conditions are met.

Rewiring your Brain

Your brain may not be as plastic as it was in childhood, but it’s still more than capable of an amazing degree of adaptability. So, how do we help our brains to stay plastic throughout our lives?

Creating Novelty

Human beings are creatures of habit, but that doesn’t mean you can’t still try new things. We are prone to staying in our comfort zones. However, pushing our boundaries can not only expand our horizons in terms of experiences and perspectives but assist in new neural networks. Environments that are full of novelty and challenge have been shown to promote plasticity in the brain.
Learning to play a musical instrument is one of the best ways you can encourage neuroplasticity, as it is a multisensory experience involving several different regions of your brain.
If that doesn’t appeal to you, you can try learning a new language. New research suggests that learning multiple languages results in changes in brain plasticity, with wide-ranging positive effects on working memory, creative potential, and non-verbal and verbal intelligence. Additionally, these findings seem to happen regardless of age, indicating it’s never too late to pick up a new hobby.

Exercise

We don’t need to hash over how beneficial exercise is to the body – by now, it’s common knowledge. But did you know that physical exercise improves brain health? Aerobic exercise in particular can improve memory, attention, processing speed, brain connectivity, and motor coordination. Research from the University of California in Los Angeles showed that regular exercise can lead to an increase in growth factor-I which helps to grow new neural connections in the brain.
Exercise has also been shown to promote pattern separation, which is a process that helps us differentiate between similar events in our past. Not only that, but an increased blood flow to the brain also results in increased cell growth.
With all the evidence of how beneficial working out can be for you, there’s no reason to not incorporate some sort of aerobic exercise into your life. Full-time students at SMU pay for access to the Homburg Centre as part of their tuition. Or, if you don’t want to go to a gym because of COVID, you can always go for jogs in the morning or try at-home routines from YouTube. Any movement that gets your heart pumping is good for you, so try to find something you can enjoy.

Reading Non-Fiction and Playing Video Games

This might come as a surprise for some people, but video games can also improve brain health if played in moderation. A paper published in 2017 in Frontiers in Human Neuroscience showed that video games can enhance brain performance and can also change brain functioning. Specifically, gamers have shown improvements in sustained and selective attention (with enlarged right hippocampi for long-term gamers), as well as increased competence in parts of the brain that control visuospatial skills. 3D games have also been shown to significantly improve the formation of memories.
So, the next time you’re on your console, you can feel a little less guilty about how you’re spending your time – granted you’re still gaming in moderation. Too much of anything isn’t good for you.
Similarly, reading non-fiction books can result in changes in the resting state connectivity of the brain that persist even after you’re finished the book. One study conducted by Emory University in Georgia, U.S., showed heightened connectivity in an area of the participants’ brains that is associated with language receptivity. The researchers also noted increased connectivity to another area of the brain that is related to representing somatic sensations - a phenomenon called grounded cognition. For example, thinking about swimming can trigger the neurons responsible for the physical act of swimming. Finally, reading can also increase your working memory and attention span, as well as improving your ability to empathize with others.

The bottom line is that as long as you find an experience new and challenging, you are helping to form new connections in your brain. So, if you’ve always been apprehensive of math, push yourself by spending an afternoon working on a beginner-level Sudoku. Or, even if you think you have two left feet, try out salsa classes. You’ll be surprised at what your brain can achieve under challenging situations, and how beneficial it can be in the long run.

Claire KeenanJanuary 25, 2021