Our brain uses a combination of senses to provide information about where our body parts are.
This awareness is known as proprioception.
Although this mostly comes from internal body information,
it can be tricked or confused by external senses such as sight and touch.
In this activity your kids will work through a number of illusions
that are designed to trick and confuse your brains ability to sense your body.
So first of all we're going to do a little experiment:
I'd like you all to touch your nose.
Wow you're so clever, you can all touch your nose!
As well as having senses like sight and touch you also have a sense of where your body is.
This can be introduced with this simple demonstration.
Now what I'd like to you do, slightly more challenging,
is take your finger from your nose, put it behind your back,
close your eyes... now touch your nose.
Wow, took a little bit longer but you all managed to find your nose,
Give yourselves a quick round of applause!
So the sense that is at work that makes you know where your own nose is,
even when your eyes are closed,
is called proprioception.
Can everyone say that?
"Proprioception".
Proprioception!
And today, we're going to do lots of experiments to find out how proprioception works,
So we're gonna have some illusions that will blow your mind!
Are you ready? Yeah!
There are 8 illusions which you can work through in this activity.
Each of them are designed to trick or confuse your senses in a different way.
Don't worry if some illusions work better than others, everybody responds differently.
Many of these illusions work best when you don't know what to expect,
so try them out on your children before telling them what will happen,
this way they should get the full effect.
The ‘working in a mirror’ challenge shows just how
disorienting it is when what you see doesn’t line up with what you feel.
Sit at a table in front of a mirror, with something blocking your direct view of your
hand.
Looking only in the mirror,
try to write your name
and if you want a real challenge try completing the maze which you can find on our website.
The ‘rubber hand illusion’ is a classic experiment
to show how our sense of self can be tricked.
Sit your child at a table, with a screen slightly to one side,
blocking the view of one of their hands.
In front of them, create a fake hand with a stuffed rubber glove
and a towel to hide the space where the rubber glove’s arm would be.
Now using a paintbrush, stroke both the rubber hand and the hidden real hand for about a minute
The participant should start to feel that the rubber hand is actually theirs.
If you want to see how well it's really worked, try surprising them by slamming the fake hand.
Try this to give someone the sensation of having six fingers!
Set up the participant in front of a mirror like this
and ask them to look at their reflection in the mirror.
The other hand should be hidden by the mirror
On both hands stroke each finger, from knuckle to fingernail at the same time,
counting each finger as you go.
Repeat it again, but this time, on the hidden hand
stroke the inside of the little fingeron ‘5’,
and then add a sixth stroke, on the outside of the little finger.
On the visible hand you should pretend to stroke an invisible sixth finger
next to thelittle finger.
They should feel like they have a sixth digit!
This simple illusion demonstrates how your brain can get confused
when different body parts feel different things.
Cross your fingers like this, and stroke them across your nose.
Because the outside edge of your fingers are touching the nose,
it might feel like you have two noses!
Get your child to stick their arms out, with their thumbs facing down.
They should then cross their hands over and interlock their fingers.
They should then twist their hands downwards and then pull them back up towards their body
Ask your child to wiggle a single finger on their left hand,
it's likely that this tangled orientation confuses their brain
and makes getting correcthand a little tricky!
Try the ‘cutanous rabbit’ to investigate how precisely our body can locate sensations.
Ask your child to close their eyes and stick their arm out.
Next, tap them 4 times at the wrist, 3 times just above the elbow, and then twice on the
upper arm.
Try to make sure that the taps are at a constant rhythm.
It should feel like that taps were spaced across the arm,
rather than in the individual areas.
This illusion should give the impression that your arms are sinking through the floor.
Get your child to lie down on the floor with their arms straight out and eyes closed.
Carefully hold their arms up by the wrists and hold them for about a minute,
then very slowly lower them back to the floor.
As the arms are slowly lowered, the child should feel that their arms are falling through
the floor.
Finally, the ‘heavy boxes’ test demonstrates how expectations based on the appearance of
an object
can conflict with how heavy we perceive an object to be.
In this demonstration, place two equal weights inside boxes of different sizes,
cans of baked beans or soup work well for this.
Get your child to lift each box and then ask them which they think is heavier.
People tend to assume that the smaller box is heavier, even though they actually weigh
the same.
You can turn this activity into a scientific investigation by recording your observations
in a table.
For each illusion you should note which senses are being confused
and then rate the level of confusion out of 10.
It felt like my elbow was going through already and my hand was still trying to get through!
I think it was tricking my touch, and that would be a 9.
Looking over the table, they should start to realise that removing just one of their
sense,
especially sight, is enough to disrupt their brain's understanding of what is going on.
I felt like that was my real hand because I couldn't see the real hand,
and when she stopped stroking this hand I thought she was stroking this one!
Which of the experiments did you find the most puzzling, and why?
OK, Naimah...
Throughout the activities don't forget to ask your kids loads of questions
about what they think is going on
and how their brains and their body's are being confused.
The kids have had an absolutely brilliant time today.
If you've enjoyed this video and want to try the activities for yourself,
don't forget to visit the Royal Institution website,
and don't forget to like and subscribe to this channel.