When Your Thoughts Run Away With You

My mom is a visually impaired nonagenarian. A few years ago, she started seeing things: colourful patterns on the floor and walls. Next came people, in pairs and dozens, going up and down escalators. Then car traffic showed up in the kitchen. She easily recognized that her hallucinations weren't real: they never goaded her or even interacted with her. A Swiss scientist named Charles Bonnet first described similarly benign visions in his own grandfather 250 years ago. About a third of people experiencing degrees of blindness later in life will develop the syndrome named after Bonnet.

Apparently, if parts of your brain don't have enough visual input, they'll start making images of their own volition. Clusters of specialized cells in our brains are customized during the act of learning to recognize things such as facial features, for example. It's why we see faces in car grills or wood grain. When those cells don't have enough input, they "think" those remembered images into being.

As Bonnet codified this syndrome, he marvelled at how "the theatre of the mind could be generated by the machinery of the brain."

We have less control over the relationship between our brains and the facts and stories inside them than we might think. Consider, for example, all the work that takes place inside our brain as our conscious mind sleeps.

"When a person is in a resting state, there's a network of structures along the midline of the brain that are active," says Clayton Dickson, a psychology professor working with the U of A's Neuroscience and Mental Health Institute. "The same network shows up when you're lightly anesthetized or starting to fall asleep." Even in the absence of inputs from the senses, this network connects disparate parts of the brain and has a role in consolidating memories and socking them away. This important aspect of how we learn is a focus of Dickson's lab. But the default neural network doesn't act alone.

The theatre of the mind is generated by more than the machinery of the brain. We're awash in chemical neurotransmitters, too. Serotonin is a familiar one, the dearth of which is associated with anxiety and depression. A couple of studies indicate serotonin has an important role in memory. But here's where it gets weird: this part of the machinery of our brains is not in our head at all, but in our bowels.

"The more I dig into it, the freakier it gets," says Anna Taylor, neuroscientist and assistant professor in the Department of Pharmacology. "People often think of bacteria as 'the other,' but symbiotic bacteria make neurotransmitters, which bind to our receptors and activate regions in our brain." In fact, 95 per cent of our body's serotonin is made in our gut, thanks to the interaction between specific human cells and our bacterial colonizers.

Give it a minute: part of how we learn depends on other species living inside our gut.

During work she started in her post-doc and finished at the U of A, Taylor and her team found that gut bacteria of lab mice in opioid withdrawal existed in different abundances than they did in healthy mice. So, she transplanted the fecal matter of mice who were in withdrawal into the colons of the healthy mice. "We saw the healthy animals start to behave as though they were in opioid withdrawal. And we saw inflammation in their spinal cords and brains," she says. Though they'd never had an opioid, the composition of the introduced gut bacteria changed their behaviour, rewiring their "learning" process, making the mice less apt to behave in typical ways.

But we are not slaves to our neural networks or gut colonists. A man from Sherwood Park, Alta., brings good tidings about the conscious steps we can take to enhance our ability to learn, by making the task of memorization easier.

Jim Gerwing, '83 BPE, '14 MEd, just happens to be the winner of the 2019 Canadian Memory Championships. He believes a person's memory is more or less a genetic fait accompli. "But it's something you can hack," he says.

"I was taking a developmental anatomy class and I had to learn the stages of development of the fetus - all these Latin terms!" he says. So, he tried a technique known as a "memory palace," which involved an imaginary walk-through of a place he knew well - his apartment - and he assigned specific Latin terms to individual household items.

After this exercise, Gerwing was able to recall 100 per cent of those unfamiliar terms in the correct order. Memorizing is not exactly learning, but once you've committed the facts to heart you are free to recall, analyze and apply them in different contexts.

Aside from making him a memory champ triumphing over competitors decades younger, 60-year-old Gerwing says his memory work (yes, it's work - he trains every morning) helps him in other ways. He doesn't keep a calendar, doesn't need a grocery list. He's great with names and faces and he can deliver a speech calmly and accurately without notes. "And it helps me really be present in the moment," he says. His approach to hacking memory is kind of inspiring.

When we consider that clusters of cells in our brains can generate visions based on past learning, when we find that gut composition may change learning behaviour, when we imagine our default neural networks firing up while we rest - it's nice to know that guys like Gerwing are trying to take charge of the process.