Each eye has a spot with no light receptors where the optic nerve leaves; the brain paints over the gap.
Wacky Facts
Every fact below is short, true and sourced: tap the source link under any of them to check it yourself. Share the ones that surprise you, or browse all topics.
We rate things higher if we built them ourselves.
The “IKEA effect” shows people value products more when they assembled them.
People remember unfinished tasks better.
The Zeigarnik effect suggests interrupted tasks stay on our minds, which is why cliffhangers work.
Sleep helps you remember.
During deep sleep the brain replays and consolidates what you learned during the day.
Yawning is contagious — even reading about it.
Seeing, hearing or even thinking about yawning can trigger a yawn.
Anchoring changes how much we will pay.
Seeing a high “original price” first makes a discounted price seem like a better deal.
People remember the start and end of a list best.
The serial-position effect: items at the beginning and end are recalled better than those in the middle.
We can recognise a face in about 100 milliseconds.
A specialised brain region, the fusiform face area, responds quickly to faces — and makes us see faces in clouds and plugs (pareidolia).
Deja vu may be a memory glitch.
Researchers think it happens when a situation feels familiar without our recalling why.
Choice overload can stop people choosing.
In a famous study, shoppers offered 24 jams were less likely to buy than those offered 6.
The Dunning-Kruger effect: beginners overrate their skill.
People with low ability at a task tend to overestimate their competence; experts often underestimate theirs.
Humans can hold about four chunks in working memory.
Modern estimates put working memory capacity at about four items, which is why phone numbers are split into groups.
The “Baader-Meinhof” effect makes things seem to appear everywhere.
After learning something new, you notice it constantly — called the frequency illusion.