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That's right. It's time for Michael's toys a walk down memory lane for all of you hockey fans out there.
Today we're gonna talk about an illusion that I witnessed when I was in Australia
I was in Sydney for Braincandy Live and I stayed in a hotel that had a magnificent view of the Sydney Opera House
Take a look.
It's a beautiful view right? Watch what happens though, as I walk away from the window.
The Opera House appears to grow larger or closer filling up more and more of the window until it dominates the entire view
Okay so, obviously as I walk back and forth across my hotel room, the Opera House isn't physically changing size. It's just appearing to.
This effect reminds me of a couple classic illusions, the first is the Ebbinghaus illusion
We've all seen this one before we've got two orange circles. Now the question is which one of these circles looks larger?
Since you've probably seen it before I'm sure you answered
They're both the same size, and you would be right; both of these orange circles are exactly the same size
But people tend to say that this circle looks larger than this circle. That is, the circle surrounded by smaller circles looks bigger.
So why?
Is it because the circles that surround it are smaller? Does our brain get tricked into thinking that things are bigger if they're surrounded by smaller stuff?
Probably. But is that necessarily what's going on in my hotel room?
You see something else is going on in the Ebbinghaus illusion
Not only is this circle, the one that tends to look larger
Surrounded by smaller circles, the circles that surround it are also closer to it
Because this circle is surrounded by larger circles those larger circles necessarily have to form a ring
That's further away from this orange circle, so there's a larger gap in between them
So what's causing this circle to tend to look larger?
Is it just the smaller circles around it?
Or is it also the fact that it's more crowded, that it's container is smaller
Well one way to investigate this difference is with the Delboeuf illusion
This is a simplified version of Ebbinghaus where instead of changing the size of what makes the container,
we're only changing the size of the container itself, instead of using big circles, we're using rings
Now, which of these circles, the black solid circles in the middle, appears larger to you if you said they both look the same size
Well then you're pretty smart and have probably had a lot of experience with illusions because yes, they are the exact same size
But people tend to say that this circle
Appears larger the effect is quite mild
I find it more mild to me than the Ebbinghaus illisuion
But the fact that people do tend to say that the circle
Surrounded by a smaller ring looks larger, leads credence to the idea that the size of the container something is in
Does affect how we perceive its size
So let's go back to the Opera House illusion when I'm right up against the window, the Opera House is pretty far away.
When I am on the other side of my hotel room
It's still pretty far away
So it's angular size, the angle that it takes up in my field of view has not changed very much
But the window which is much nearer to me at all times is changing its angular size
Quite quickly when I'm up right against the window
I can't even see the edges of the window in my field of view
But from the back wall of the hotel room I can see the whole window
So what this means is that as I walk backwards
the container that
surrounds the Opera House, the window
Shrinks at a faster rate than the Opera House does, so what I'm left with is pretty much a version of this
figure from the Delboeuf illusion.
That probably has something to do with how this illusion works more so than the size of
What surrounds the Opera House, because the objects that surround the Opera House when I'm near the window are
Smaller in angular diameter than the objects that surround it when I'm on the back wall of the hotel room
The illusion was really fun and honestly
I spent
most of my time in that hotel room
walking back and forth
enjoying the illusion you can see it for yourself by looking at anything out of any window as you walk away from the window since it's closer
To you its angular diameter will shrink at a faster rate than what you see out the window and whatever
It's framing will appear to get larger
We have a lot to learn about our visual systems from illusions like these because we still don't have all of the answers
But there are some very intriguing things about them
For example
What we do know about the Ebbinghaus illusion is that we are not
Born to be fooled by it if you show this illusion to young children like under the age of 10 or under the age of
Seven they tend to not be fooled they say well both orange circles are the same size. What do you mean?
So, there must be something that we learn as we grow up that teaches us to be more
Context-sensitive to perceive objects that are maybe surrounded by smaller stuff maybe in smaller containers to be
Larger, but this is only a perception thing not an action thing other studies have found that if you would present this illusion to adults
Who are fooled by it
But then you ask them to reach out and grab
One of the orange circles in the middle they will form the same grip size
for each circle
Now this is considered evidence for what's called the two-streams approach to vision.
The idea that our visual processing center has two different modes, one is perception how large we think things are how far away they seem, and the other
Controls our muscles our actions. How we interact with those things and that part
Isn't fooled by the Ebbinghaus illusion, the Delboeuf illusion
also
Has all kinds of great little treats to give us one is that it may play a role in how much food we eat
You see if you ask someone to put some food on a small plate like this
And then you give them a larger plate and tell them to put the same amount of food on it
They tend to put way more food on the bigger plate while thinking that they put the same amount on now
Researchers have found that in the last say about a hundred years the average plate size has increased by about
fifteen percent so
That coupled with the Deloeuf illusion may be one of the things behind us possibly eating more nowadays
I have done many many videos in the past about angular size so be sure to check those out
It's a fascinating topic and the illusions that it is
Responsible for are just... well they're just a blast we still have so much to learn from them. Please stay curious and
Applier your curiosity to making the world a better place and as always mug
Cilinder for watching