From the moment we’re born, we begin the lifelong task of learning: how to control our bodies, how to communicate, how to read social cues from friends and strangers. By adulthood, we’re capable of more complex thoughts, actions and emotions than any other animal on the planet.

Doctors and twin brothers Chris and Xand van Tulleken examine the latest science in Secrets of How We Learn, a documentary presented by The Passionate Eye. Here are a few things they discovered.

Our brains physically change when we learn a new motor skill

Danny MacAskill is a Scottish trails cyclist who’s honed his craft by practicing tricks and riding skills for several hours a day for more than a decade. Watch a video of his incredible skill.

MacAskill makes controlling his bike look easy, but he doesn’t have a superpower; the process of learning a new motor skill is the same for everyone.

Our brain changes physically every time our body learns how to do something new. As we try out a new skill — whether it’s walking, juggling or doing a handstand — our body gathers information and feeds it back to our brain. 

As we attempt the skill over and over, a new neural network is perfected, with cells called oligodendrocytes building a myelin sheath (white matter) around the pathway. This new sheath ramps up the speed at which information can be transmitted — by 100 times, according to the documentary — creating a superhighway that makes a mastered skill feel effortless.

As we get older, our brains’ resources dwindle and our networks become more fixed. But it’s not impossible to learn new skills in old age. With enough practice, we can still change the physical structure of our brain.

Rhythm may be key to learning language

The ability to match our bodies to a beat appears to be a skill we’re born with. Babies have been observed doing it long before they’ve properly learned how to control their movements.

And it turns out, our sense of rhythm may be key to learning a language. Research by Reyna Gordon, a professor of otolaryngology at Vanderbilt University Medical Center, showed that primary-age school children who struggled with musical rhythm also tended to do poorly on a spoken grammar test.

Now, Gordon’s speech therapy students are given violin lessons and movement classes along with language therapy to take advantage of those potentially linked brain networks.

Sleep may be critical in forming lasting memories

In our lifetime, we’ll learn about 75,000 new words, says Xand, which is like memorizing an entire dictionary.

To commit a new word to memory, we need to stimulate both our visual and auditory cortexes (by seeing the word and saying it out loud, for instance). We also need to trigger our anterior temporal lobe by understanding the word’s meaning to create a lasting “map” for each memory.

But there’s more. Scott Cairney, a professor of psychology at the University of York, believes that sleep may improve our chances of remembering words, too. In the documentary, we see him administer a simple test on Chris that involves word-picture associations and a short nap — and sleep improves Chris’s ability to recall those associations.

Cairney thinks that slow-wave sleep in particular may be key in eradicating the information that we don’t need and strengthening important information so we’re less likely to forget it after sleep.

Crying is one of the first visual expressions of emotion that we come to understand

As we mature and navigate our social worlds, we learn to read each other’s facial expressions, which are important in understanding emotion. According to the documentary, there are six basic expressions found across all cultures (happy, angry, surprised, disgusted, scared and sad), plus many thousands of micro-expressions that can flicker across a face. All give clues to how we really feel to a keen observer.

But one of the first, and perhaps most important, visual signals of emotion we come to understand is a powerful one that starts with a single drop of water from the eye: crying. Emotional crying is thought to be uniquely human, and it’s so important that we can do it, and understand it, even before we can talk.

Tears have a profound effect on others and typically signify an intense need. Biologists suspect that we learned to care about each other long before we could say it with words, the film notes.

Our body ‘learns’ to adapt to the unique circumstances of our lives

Even though Chris and Xand are identical twins, they don’t live identical lives. In this video clip, they discuss how they look quite different.

Chris and Xand’s bodies have adapted to adjust to the unique circumstances of their lives, just like Freya Christie, a British tennis player who hits more than a thousand forehands a day in her quest to be at the top of her game. The bones in her racket arm are 20 per cent thicker and contain more bone mineral than the arm on her other side. In other words, Christie’s skeleton has “learned” to cope with her intense daily workouts by growing to reduce the risk of breaking.

According to the documentary, skeletal muscle is “the most adaptable tissue in the human body” because muscle fibre cells contain more than one nucleus. When muscles are worked, special satellite cells are activated which divide and fuse with the muscle cells. With the added nuclei, the muscle cell can build more myofibrils, which increases its size — and in Christie’s case, improves that wicked forehand.

For more, watch Secrets of How We Learn on The Passionate Eye.