9 Brain Tricks To Test On Your Friends

The human brain is a wonderful thing but there are some things that seem to make it malfunction.

Here are Nine-Stein’s best 9 Brain Tricks for you to test on your friends so next time you are at a party you can whip some of these out and have some fun and laughter.

  1. Thumbs Up! (aka Trigger Finger)

Get a friend to make one hand into a thump up gesture, and tell them to make the other hand into a pointing finger gesture – with the index finger pointing towards the hand showing the thumbs up gesture.

The challenge then is for your friend to simultaneously swap gestures, so the hand which is showing the thumbs up gesture changes to become the hand which is pointing the index finger and the hand which was doing the pointing swaps to become the thumbs up gesture.

It sounds so simple but it’s actually annoyingly tricky. Definitely worth betting a round of drinks with your mates on this one.


  1. The Hermann Grid

An easy challenge here, just ask a friend to count the black dots between the squares in the image below.


It’s actually impossible to do. Each time you move your eyes and re-focus, you see that the dots in the centre are white but the surrounding ones appear to black so you move your eyes again trying to catch them and what was black is actually white and so on.

  1. The Stroop Effect

Here’s a great one to play if you want to test a friend against the power and might of a 5 year old.

Ask the challengers to say the name of the colours of the words from the image below – the first one is easy there is no conflict between the written word and the colour.


Now, let’s up the ante! A timed race against a five year old. Same rules, say the name of the colours of the words to the image below.


Oh, not so fast now, are you? This interference in reaction time is known as the Stroop Effect. While our eyes can see the colour ‘pink’ the word says ‘purple’ and the brain has to slow to a crawl to untangle these mixed signals. However, for a child who has yet to start reading properly, this exercise is a doddle as there are no mixed signals being sent.

  1. Let it go!

Another one which most children can do easier than most adults – ask a friend to put their hands together the same as in the image below.

separate the ring finger

Insert a coin in between their 3rd fingers and ask them to separate those two fingers but the other fingers must remain as they are. It’s not as easy as it looks – I can assure you.

  1. Milk and Orange Juice Test

A blindfold challenge now; the bet is for a friend to be able to taste the difference between three variants of milk. The first being full fat, the next is semi-skimmed milk and the third is skimmed milk.

Well, that’s not much fun, so swap one of the milks for a glass of orange juice. Get the challenger to sample the first glass of milk and take their answer, move on to the second glass of milk, all the time building the challenge up so the brain gets working a maximum output to separate these slightly different tastes.

Move on to the 3rd glass and this milk is replaced with the orange juice. The challenger’s brain is expecting a milky flavour to come but it is greeted with the sharp contrast of the orange juice. Gagging and vomiting might follow so be prepared.

OJ and milk

  1. The Sander Illusion

Place your bets; look at the two blue lines (on the image below), which one do you think is longer – the one on the left or the one on the right?

sander illusion

Ah, the eyes and brain are playing tricks on you again. They are actually both equal in length. Crazy.

  1. What the F?

Ask a friend to read this sentence and count how many F’s are in the text. Not sure why but most people say 3 or 4. Under closer inspection, there are actually 6 F’s in there.

nine-stein brain games

  1. Hand and Foot

Ask a friend to sit down and stretch out their right leg and raise it off the floor. Then instruct them to move their foot in a clockwise circling motion. While they are doing this, ask them to draw a number 6 in the air with their right index finger.

The challenge is to continue doing the clockwise circling motion with the foot – sounds easy? Give it a go and find out.

nine-stein brain teasers

  1. The Ganzfeld Experiment

We finish off with a right strange one – the Ganzfeld Experiment. Ask a friend to relax in a chair or by laying down on the sofa. Next you will need an MP3 player which is playing some white static noise. Cover the friend’s eyes with half a ping pong ball (half a ball over each eye) and tape them in place. Finally, you will need a red light to shine in their direction.


Due to the state of sensory deprivation, the mind starts making up its own fairytale. You’ll be amazed at what some people report seeing or imagining. Well worth a try and 100% legal.

We’d love to here which ones you tried and what your favourite one is. Drop us a comment below to let us know 🙂


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s