why does our brain play tricks on us? Shouldn’t it “protect us” by not scaring us?



I”ve posted this in another sub too but thought maybe I get a more detailed info about our brain here.

Basically I read on the good old internet that if you stare for a period of time into the mirror that your brain will start playing tricks on you and scare you. Well I wanted to see for myself, indeed it did happen. A few times I thought I’ve seen someone behind me for a split second, or that my face moves even tho I didn’t move a muscle etc. Why would our brain do that to ourselves since it could harm us by making us panic therefore it being bad for our brain? Is there any reason that our brain does that? I’m quiet certain it’s not to protect us is it?

Additionally does this maybe explain why people say they seen bloody marry or other ghost storys connected to mirrors? That our brain for some reason plays tricks on us? Since if we go into the bathroom and we expect to see bloody marry by doing that ritual that our brain tricks us and makes us see it just cause we expected it to be there?
Maybe Im thinking too far

Why does our brain do this? Shouldn’t it do the opposite and protect us from it?

In: Biology

I’m sure someone will give you a more detailed answer but to simply explain what our brain is up to:

Or brain is wired to protect us from physical danger and harm, but it can cause us psychological distress while doing so. So when you’re staring into a mirror, as you get used to the view in front of you, your brain start scanning for threats around you, and since the greatest threat cash come from behind you where you can’t directly see, in a reflective surface your brain gets more active making sure there are no threats behind you.

Now if in this situation you start to panic, small things like a dark spot in your vision from increased blood pressure can be taken as a threatening shape that you saw in your mirror. And since your brain can’t fully process what it saw, it can make you think of ghosts of macabre images to match what you might have glimpsed at.

Which is more protective, getting scared by something that turned out not to be there, or not getting alerted when something was there?

The first situation is a slight spook, the second is death-by-tiger. We evolved to err on the side of getting spooked, so no, the brain shouldn’t “protect us” by not alerting us at the slightest hint of a threat.

your brain is a time machine. it tries to predict what will happen in the future so it can protect you from danger that hinders your survival.

that machine is optimized for scenarios where real danger is present (cause it really can make a difference to your survival). While false scare to no danger doesn’t really impact your survival.

To add to what others have said (correctly) about risk/reward (better to recognise 9 false risks and 1 real then 0 false risks and 0 real when it’s there), it’s also helpful to think about how we process our senses, particularly vision. Our brains are amazing pattern recognising machines. They take signal which is just light hitting certain cells in the eye, turn it into electric codes, then produce a coherent image. When information is missing, it fills in what it expects to keep a coherent conscious image of the world. For example, your field of vision contains a blind spot (where the optic nerve leaves the eye), and your peripheral vision is in black and white. We notice neither of these things because the brain uses a combination of information from our two eyes and our expectation/previous knowledge to construct a single, unified visual representation. The brain has a variety of patterns of light it looks for which are useful for building up the single image from the information it’s getting.

This is why we are so susceptible to visual illusions. Your brain is not tricking you – it is trying to make sense of incomplete (and sometimes contrasting) information. What you perceive is essentially your brain’s best guess at what’s going on. So in terms of these mirror tricks you’re talking about, it’s a combination of heightened attention to risk (especially if you feel as if you’re in danger) and your brain interpreting light patterns. *It* is being tricked, not tricking you.

* Human brains have evolved to work on the principle of “Better Safe Than Sorry”
* So it will react to false alarms more than it will ignore a real threat.
* It’s also very good as tuning out things that are just normal background noise.
* But if you force yourself to stare into the mirror, it’s like telling your subconscious mind that there is something it should be finding, so it looks harder.