Ever get that slightly weird feeling when you step onto an escalator that isn’t moving? For many people, there’s a moment of disorientation when you first step on and start climbing - even when you can clearly see that at that particular moment, the escalator is basically a set of stairs.
But why is this?
Well, it’s all to do with the way your brain processes information and makes decisions.
The brain has two systems; conscious and non-conscious. In many situations your non-conscious brain takes over. For example, you don’t consciously think about every single step you take.
This non-conscious system is what stops you from falling over when you step onto an escalator. Your brain has learned from past experience that you need to sway forwards slightly to adjust for the movement - and so whenever you step onto an escalator, it accounts for this movement automatically.
But it seems that even when you can see an escalator has stopped, you cannot completely prevent your non-conscious brain from expecting movement.
The Broken Escalator Phenomenon
This phenomenon was investigated in a 2003 study by R.F. Reynolds and A.M. Bronstein entitled ‘The Broken Escalator Phenomenon’, which they defined as “an odd sensation of imbalance, despite full awareness that the escalator is not going to move.”
The Atlantic describes the study:
To recreate the feeling in an experimental setting, the researchers used a mobile sled, which participants stepped onto from a stationary platform. First they stepped onto the sled 10 times while it wasn’t moving, then stepped onto it 20 times while it was in motion. Then the researchers stopped the sled, clearly told the participants it wouldn’t be moving, and had them walk onto it again. Even though they knew the sled wasn’t moving, they still walked onto it too fast, swaying their torsos forward. “There was a forward sway of the trunk by about 14.9 centimeters above that of the final resting stance position,” the study reads. Many of the subjects said they were surprised by the feeling, and some of them compared it to walking onto a broken escalator.
The effect was less pronounced when the participants knew that the sled would stay still when compared to times where the researchers surprised them - but the participants still swayed to counter the non-existent movement in both situations.
A similar effect has been demonstrated in people who cautiously step on a previously-slippery surface, even when they know it’s no longer slippery.
This example really shows the power of the non-conscious brain and gives a real insight into how many of our behaviors we do without thinking.