Why your brain holds on to all the s***

Ever wondered why you fall asleep thinking about the one thing that went wrong that day, despite all the good stuff?

The answer’s surprisingly simple, our brain has a negativity bias. If you’re a caveman and you make a mistake — let’s say you drink water from a stagnant pool. If you survive the experience, then it’s important for you to learn your lesson — don’t drink swampwater! So evolution has selected for negativity. The cavepeople whose brains remembered the bad stuff about drinking swampwater were less likely to do it again and more likely to survive, whilst the happy-go-lucky cavepeople…they didn’t last so long.

Over time that results in a human brain that is very good at taking in and holding on to all the s***; and much worse at balancing that with the good stuff. The exact ratios are disputed but most studies on the topic show that a ratio of at least 5:1 (good to bad) is what your brain needs in order to perceive things to be balanced.

That negativity bias served a very important purpose in the Stone Ages, but it’s highly problematic today, causing a whole range of problems: negative self talk, aversion to risk, lack of motivation, friction in relationships, internalising self doubt and more severe mental health issues, to name just a few. We don’t need it anymore for the sake of survival, and in a time of overwhelming access to information and media that skews heavily towards the negative, it’s no wonder that our collective mental health is suffering.

The good news though is that hope is not lost! (Read that sentence five times to try and provide balance). You can seek solace in the concept of neuroplasticity, which essentially states that the brain can change with the right stimulus; or ‘neurons that fire together, wire together’ in the words of Donald Hebb.

Yes, the factory settings of your Stone Age brain may be to retain negative information, but if you’re willing to put in the work, then you can gradually change that programming to be more favourable. It’s not something that happens quickly, nor is it something I’ve personally mastered, but it is something we can all make progress with.

There’s no one-size-fits-all answer of how to make progress, but there are a range of strategies with solid evidence, including:

• Choose what media to consume — spend less time doomscrolling and more time taking in the positive going on in the world. Media outlets such as Positive News are entirely devoted to bringing you the good news stories.
• Become aware of the way you talk to yourself and try to balance the conversation — most of us would never speak to someone else as critically as we talk to ourselves. Try to notice when this happens and make sure you give the other (more positive side) of the internal monologue some airtime. One way can be to focus on the facts — if your inner critic is telling you that you’re a failure, then try to think of factual things that provide evidence that’s not true.
• Practice gratitude — the simple act of talking about or writing down three things you’re grateful for each day has been shown to have a positive impact on mental health. My partner and I tend to do it on our morning dog walk.
• Pay attention to the core stuff: exercise, sleep, diet, time in nature — good for you in every way and will make sure your brain is getting a positivity hit.
• Breathwork and meditation — there’s a major body of evidence around this, plus thousands of years of Eastern wisdom. Of particular interest when it comes to negativity bias, are meditation practices that focus on positivity e.g. loving-kindness meditations.
• Psychedelics — still mostly illegal but there is some incredible clinical evidence around the role that psychedelics can play in rewiring the brain for the better with illnesses such as depression and addiction, and they seem destined to become a more staple part of our treatment and management of mental health in future.

So at the very least, I hope the next time you fall asleep thinking about the one thing that went wrong that day, you can console yourself with an understanding of why it’s happening. Hopefully one day we all find ways to fall asleep to the good stuff too.