That Neuroscience Guy - Mindfullness and Meditation

Episode Date: September 26, 2021

Have you ever wondered if meditation can actually improve your health? As it turns out, practising mindfulness and meditation improves various brain functions, and alleviates some negative mental health symptoms. In today's episode of That Neuroscience Guy, I explain the neuroscience of how meditation changes your brain for the better. 

Hi, my name is Olof Kregolsen, and I'm a neuroscientist at the University of Victoria. And in my spare time, I'm that neuroscience guy. Welcome to the podcast. Meditation and mindfulness training has been practiced by cultures all over the globe for thousands of years. But what is meditation and mindfulness and how does it work? Meditation is typically defined as a set of techniques that are intended to encourage a heightened state of awareness and focused attention.

Meditation is a consciousness-changing technique and it's been shown to have a wide number of benefits on psychological well-being. But how does it work? What is the neuroscience of meditation? It's important to note at the outset that there are many different kinds of meditation. There's focused attention meditation, where you're focusing your attention on an object or an idea to enter a meditative state. There is open monitoring meditation, where you're paying attention to your body systems and getting in tune with yourself. There's transcendal meditation, where you're trying to raise yourself to a different mind state. And there's loving kindness meditation, where you're

practicing themes of compassion. And there's many other styles of meditation. For simplicity's sake here, I'll just talk about common themes that are observed during meditation in general. From a scientific perspective, meditation can be likened to enhanced self-regulation, specifically controlling different brain networks, such as the attention networks, the emotional regulation networks, and the networks that are associated with increased self-awareness. But what does that actually mean? Control of attentional networks is associated with regulation of the posterior parietal cortex. It's a region of the brain just back from the top of your head,

and this region has been shown to play a key role in focusing attention. When you're paying attention to something, the posterior parietal cortex is active, and there's increased firing there. And in fact, if you recall from last season, damage to the posterior parietal cortex results in all sorts of issues such as neglect. The idea here then is that meditation modulates firing in this brain region. So during meditation, you can change the firing patterns in the posterior parietal cortex. Another brain region that's associated with the control of attention is our old friend, the posterior parietal cortex. Another brain region that's associated with the control of attention is our old friend, the anterior cingulate cortex.

The anterior cingulate cortex plays a key role in sort of controlling attention, if you will. So the posterior parietal cortex is deploying attentional resources, and the anterior cingulate cortex is kind of in charge of it, like the boss keeping an eye on a worker. And again, when people meditate, we see changes in activity in the anterior cingulate cortex. It's one of the most consistently reported findings. Now, if we think of emotional regulation, it's our old friend, the amygdala. If you recall, it's a midbrain structure attached to the front of the hippocampus, and you have two of them, a left one and a right one. And the amygdala plays a key role in our emotional responses. So if you remember when we talked about emotion,

if you see a significant other, the amygdala fires more. And when you're experiencing emotional events, the amygdala fires more. And it's actually why you remember things that are emotional more than things that aren't. Anyway, the amygdala also plays a role in emotional regulation. It helps control our emotions and our emotional state. So again, the idea is that during meditation, we're modulating the firing in this brain region, which helps us improve emotional regulation. But what about self-awareness? Self-awareness can generally be thought of as a whole brain process, but the prefrontal cortex in particular is important for self-awareness. As with the parietal cortex, the anterior cingulate cortex, and the amygdala, during meditation, we're changing the firing patterns of neurons in the prefrontal cortex.

And by doing so, we're helping our ability to be self-aware. And by doing so, we're improving our self-awareness. Self-regulation is also associated with changes in the default mode network. The default mode network is a series of brain regions that actually fire in synchronization when we're doing nothing. So this network is sort of like our chill network, if you will. When we're relaxed and doing nothing and not thinking about things, the default mode network becomes more active. There's a lot of theories about what the default mode network does, and we'll talk about that in a later episode. But during meditation, we see changes in firing in brain regions associated with the default mode network, and therefore that means we have improved ability for self-regulation. Research using fMRI is where this all comes from. It shows activity in these brain regions,

but it also shows brain activity in It shows activity in these brain regions, but it also shows brain activity in a whole lot of other brain regions, including the caudate nuclei, the insula, the precuneus, the middle and superior temporal gyrus, the precentral gyrus in the left hemisphere, the superior frontal gyrus, the parahippocampal gyrus, the inferior parietal lobule, and the middle of syphcipital gyrus in the right hemisphere. So basically meditation results in a whole lot of brain activation. Another really cool finding with MRI is that researchers have observed permanent changes in brain structure, the volume of white and gray matter in the brain, in people who are long-term practitioners of meditation. And these changes are good.

The changes in brain structure that are observed are associated with more efficient brain processing in people who meditate on a regular basis. EEG, or brainwaves, have also been used to study meditation. In fact, if you Google monks and EEG, you'll find all sorts of pictures of Buddhist monks wearing EEG systems so people can study meditation. Typically when people meditate you see changes in the EEG spectra. A really classic finding is increased alpha activity

in the posterior brain regions. If you recall alpha oscillations are oscillations between 8 and 12 hertz and they're typically associated with the focusing or relaxation of attentional processes, especially alpha oscillations over the parietal cortex, which of course relates to the MRI findings we talked about, where you see increased firing in the posterior parietal cortex. Another key EEG finding is that you see increases in theta oscillations. These are brainwave oscillations between 4 and 7 hertz over the prefrontal cortex. Theta power is typically associated with cognitive control, our ability to regulate our brain processes and make decisions.

Again, cognitive control is kind of like the boss. It's the person in charge of the brain, or the brain region in charge of the brain, if you will. And it is associated, like I said, with the prefrontal cortex and is reflected in theta oscillations. During meditation, you see increases in theta power over the prefrontal cortex. Another key finding is changes in gamma activity. These are similar to the other changes where we see an increase, and they're typically focused over the frontal cortex, but some researchers also report changes in gamma oscillations over the parietal cortex and over occipital regions of the brain.

Gamma is a high EEG frequency, 31 to 100 hertz, and it's still not clearly understood. The reason is pretty simple, actually. Older EEG systems had trouble actually measuring activity between 31 to 100 hertz, and it's only with newer EEG systems that we're able to get good resolution at that frequency range. Gamma activity is being associated with a whole range of brain functions, including perception, attention, memory, consciousness, synaptic plasticity, and even motor control. But what do all these EEG changes mean? What does increased alpha power and increased theta power and increased gamma activity, what does it mean?

Basically, it's reflective of the underlying brain firing that we discussed earlier. For instance, the alpha oscillations, like I said, are from the parietal cortex, so it's associated with attention. The theta oscillations are from the prefrontal cortex, which is associated with our ability to self-regulate. The science on the benefits of mindfulness and meditation is quite clear. Meditation has been shown to have a lot of positive health outcomes, including reduced stress, reduced anxiety, and alleviation of depression. And given that those are symptoms that we all experienced during the COVID pandemic, maybe meditation might be something you could think about trying to help alleviate those

symptoms if you're experiencing them due to the pandemic. Meditation has also been shown to result in greater productivity in the workplace. A lot of companies now are using meditation and mindfulness training and reporting that their employees are performing better. Meditation and mindfulness are associated with enhanced decision-making and even enhanced learning. So the science is pretty clear. We know what brain regions are activated, we can see them with fMRI, we can measure it with EEG, and studies have even been done to show that meditation is good for the brain. And in this world we have now, there's even neuroscience tools that you can take home to help with meditation. One cool one is the Muse,

made by Interaxon, a Canadian company out of Toronto. Essentially, the Muse is a mindfulness training tool. The way it works is it's a low-cost EEG headband. The headbands cost between $250 and $500, depending on the model you get. And you put on the headband, and it's measuring your brain waves. Now, some people think, really, you can measure your brainwaves for a couple hundred dollars? Well, you can. My lab published a really cool paper in 2017 in Frontiers in Neuroscience. The paper is called Choosing Muse. And basically, we put the Muse EEG headband up against our $100,000 research grade system.

And what did we find? We can measure EEG with the Muse. Now, it's not quite as good as the $100,000 system, but it's still pretty good quality EEG. So what does that have to do with meditation and mindfulness? Well, if you recall, I said there's changes in brain activity and changes in EEG firing patterns when you meditate and when you're being mindful. So you put on the Muse and you open an iPhone app. The app basically helps you learn to become mindful. When your brain is in a mindfulness or meditative state, you hear sounds that are

associated with good feelings. It's basically nice weather. And if your mind slips out of this state, you basically hear rains and stormy weather. What the Muse is doing is a form of neurofeedback. It's basically giving you feedback so you can push your brainwaves into a meditative state and gain the benefits of mindfulness. So there you go. There's even neuroscience tools you can take at home to help you become more mindful. So that's it for this week. Thanks for listening as usual. Remember, you can follow me on Twitter, ThatNeurosciGuy. We even have a YouTube channel now, ThatNeuroscienceGuy. The videos that are going up are focused on research methods, how scientists do research.

But there's a couple of other interesting ones up there as well. So I hope you enjoy the YouTube channel. And if you've got ideas for the podcast or you just want to give us feedback, you can email us at thatneuroscienceguy at gmail.com. My name is Olof Kregolsen, and I'm That Neuroscience Guy. Thanks for listening, and see you next week on the next episode.