That Neuroscience Guy - The Neuroscience of Rumination

Episode Date: July 25, 2023

It's common for quiet times in our mind to be invaded by intensly emotional memories. Whether reminiscing about happy moments or dreading the bad ones, we tend to ruminate on the past. In today's episode of That Neuroscience Guy, we dig into the neuroscience behind how and why we ruminate.

Hi, my name is Olaf 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. Have you ever dwelt on the past, you know, thought about things that have happened to you and just sort of relive them over and over. You know, like it's like you're rewinding a movie and watching it again and again and again. Sometimes these things can be negative things that have happened to us, but sometimes they can be positive things as well. But we dwell on the past. We ruminate.

So on today's podcast, the neuroscience and the reasoning behind rumination. Now, again, I want to thank the listeners, you, for this idea. This, again, was something that was sent to us. If you want to send ideas for future episodes, remember, you can follow me on Twitter at thatneuroscienceguy and just DM me an idea, or you can email us at thatneuroscienceguy at gmail.com. Anyway, thank you to the multiple listeners that suggested this topic. I have to admit, this is something that I'm kind of an expert on professionally, I guess, in terms of neuroscience,

but also personally. Now, what is rumination? Rumination, like I described in the opening, is basically when you relive events in your past, you have memories that you bring back and you keep running through them over and over and over again. Now, the reason why we do this is we're reliving our past. Literally, there's something about it that has upset us or made us happy. I want to focus more on the negative side of rumination because usually that's how people think of it. But you can ruminate about positive events. For instance, I've relived the birth of my son, Owen, countless times. But usually rumination is a negative thing. Now, the reason why we do it is simple.

Is there something about the event that has happened to us or events that troubles us or upsets us? It's caused us emotional distress. that troubles us or upsets us. It's caused us emotional distress. So when we go into sort of that default mode network situation where we're reflecting on our, you know, our life, we go to these emotional events. You tend not to ruminate about things that are meaningless. For instance, you know, if you drove home from work and nothing happened, you're probably not going to relive the drive home from work. But if something emotional happened to you, the death of a significant other, breaking up with a significant other, losing a job, things like this. Well, these are emotional events. And the way our memory works, as we've discussed in the past, is that these emotional events have what we call salience.

It's like the amygdala literally puts a big flag up and says, hey, this is something that, you know, that was important. It caused an emotional response within the brain. And when we sort of go into that daydreaming or default mode network, these things stand out to us. So when your brain is an idol, for instance, you're just sitting there staring out the window or daydreaming while you're at work, these emotional events, these things that have salience are like flags. And the bigger they were, the higher that flag is, if you will. So I'll go through one from personal experience. You know, I went through a breakup with a partner. We'd been together for a long period of time.

And I relived that breakup over and over and over again. I went through it. I thought about it. I pondered it. And the reason I did is because when I was reflecting back on my life and, you know, thinking about things, when I went to that default space, right, the space where I didn't have anything occupying my mind, that event stood out with emotional salience. My amygdala was going, oh, hey, here's something, you know, and that's where your brain goes. This, of course, is why you ruminate on things. It's also why you don't ruminate on things. So one of the things that people say is if you've had something like this happen to you is keep yourself busy. Well, the reason they're saying that to you is if your brain is focused

on something else. All right. So imagine you get into work, you're reading, you're watching a show. Well, that's caught your attention, and your brain is focused on that. The rumination part comes, like I've said, when you're in this default space where your brain isn't focused on something, and all of a sudden it's looking around for something to capture your attention. And what stands out? Well, that emotional event. The emotional event is there. It's got salience. The flag is waving and your brain fixates on it. It's really that simple. The reason you keep going back to that event over and over again is because it's troubling to you. It's literally something that your brain is focused on and you can't put your attention to someone else.

And this is why rumination can be unhealthy at some point, because, you know, it's all right to rehearse events and think about why they're good or bad in your life. But if you keep going back to that same event over and over again, we would say that's not a healthy thing to do because at some point you have to move forward. again, we would say that's not a healthy thing to do because at some point you have to move forward. And of course, for most of us and in most situations, that's what happens. Other events happen in your life. If you use the breakup example, if you will, you find someone new. And then when you start to ruminate, you're thinking about that person and events with that person. If you talk about the death of someone that's close to you, well, you never really forget about it, but other things, you know, take up that space. You might get a new pet, you might have a new interest or hobby, and then that's what you

ruminate on, if you will. You focus on the new thing in your life and you occasionally go back because that event still has emotional salience. But the way that emotional salience works is it does fade away with time. We're hardwired to do this. All right. So if you have some traumatic event that's happened to you and you're ruminating on it, like I've said, that event has this emotional salience to it, but that emotional salience will decay over time naturally. All right, your amygdala will find new things to be interested in. This is just the way your brain works. Where it can become problematic, though, is if you keep going back to that event and you don't allow new things to happen.

Well, then guess what? Every time you go back to that event, you're increasing the emotional salience of the event again, not to the same extent that was there when it happened. So say someone significant died in your life. Well, you'll have this massive emotional response. Every time you go back to it, though, you're reliving that emotional response and that strengthens the memory. If you think about what we've talked about in memory in the past, memories are strengthened largely through repetition. So if you keep going back to that event, you're strengthening the memory, if you will. And that's why it's dangerous to do

this because if you never move forward, if you will, or find new events to add emotional salience to, well, then that event just is the emotionally salient event in your life. And like I've said, that decay of the emotional response is natural. Now, what can you do about it? Well, I almost feel like it's a theme for the podcast and I joke about it with Matt all the time, but how do you avoid rumination? How do you move on with things? Well, positive brain health. And as you know, and you can probably predict what I'm going to say, sleep is crucial. Now, when you're ruminating on things, sleep can be tricky, but you know, whatever it takes, if it's a bit of melatonin, if it's exercising a lot,

you just got to clear your mind and you got to get a good night's sleep. Diet is important. When people tend to be ruminating or focused on events in their past, diet can go out the window. It's too easy to order, skip the dishes or go to McDonald's drive-thru. Well, it's a time to eat healthy things because guess what? If you eat healthy and you sleep, you have better brain health, which means you're less likely to ruminate. And of course, the third piece of the puzzle is always exercise. Exercising takes your mind off things. If you go for a run, you're focused on the run and guess what?

You're not ruminating on the past. And the other things that we've mentioned in the past when it comes to brain health apply as well. mentioned in the past when it comes to brain health apply as well. Social interaction is crucial, especially social interaction that's not promoting the rumination. You know, your friends will not want to hear the story over and over again. And some of my friends that are listening to this are probably laughing because I've done this myself and we're all guilty of it. But changing the conversation to a new topic, mindfulness activities, whether it's meditation, breathing, or yoga, or any number of things, these things are also good for our brain health. And anything that's good for our brain health will help us and stop us from ruminating.

So to recap quickly, the reason we ruminate is an event has happened in our life and it has emotional salience. And our brains, when we go into that default mode network it the your brain tends to focus on these things because they have emotional salience they stand out and the way you stop doing this is to find new events to focus on all right that's all i've got for this week um that's the neuroscience of rumination remember check out patreon where you can support us a dollar a week, a dollar a month, anything. It really helps.

And it always goes to graduate students in the Kregolson lab. There's our Etsy store. We have some t-shirts and merch up there. Of course, like I said at the outset, you can follow me on Twitter at that NeuroSci guy and send us some ideas for the next season. And of course, thank you so much for listening to the podcast and subscribing. It really helps. My name is Olive Kregolson, and I'm that neuroscience guy. I'll see you soon for another episode of the podcast.