Today on Blinded by Science, what do mountainous roads and striped dresses have in common? Read on and find out.
Chris G
asks, “When I drive in the mountains it sometimes seems like I am going down
hill when actually I am still going up. How does that happen? Has this ever happened
to you?”
To
answer your last question first, no I don’t think it has ever happened to me. But then I tend to zone out whenever I drive
anyway, so I probably wouldn’t remember if it had ever happened to me.
Wait .
. . that’s probably something I should not admit out loud.
What I
meant to say was that because I drive so very defensively, I am always aware of
what is happening on the road around me and the conditions of the road itself
so I would already know that actual slope of the road well in advance.
Or more
likely, I just don’t drive in the mountains very often so it hasn’t happened to
me yet.
Anyway,
while trying to research this topic, I think I may have found what you were
speaking about. There is
a known optical illusion in which a descending slope appears to be ascending or
an ascending slope appears to be descending.
Yashima Driveway, Kagawa Prefecture, Japan; photo by
Akiyasu Tomoeda
In the
above photo, the section of road in the foreground is descending as is the
section of the road in the background (even though it appears to be ascending). This occurs because a “trough” appears when
two sections of road with differing slopes converge. The trough causes drivers to misjudge the
incline of the road.
Well, I’ve
answered your question, but frankly I don’t want to post such a short blog post
this time (I’m sure there will be times in the future where I will, but not
this time!). So I’m going to add a small
explanation of optical illusions and why they occur.
Aren’t
I just a wonderful person?! Money and delicious food are always appropriate ways of showing gratitude. Just an FYI.
An optical
illusion is a perception,
as of visual stimuli, that represents what is perceived in a way different from
the way it is in reality. In other
words, when your brain perceives the images seen as different from what
actually exists.
Remember this dress? Swiked/Tumblr
Basically,
your brain has the task of organizing and integrating all the information
coming in from your various senses (including sight). Because of the obscene amount of information
coming in, the brain has to take some shortcuts in processing it so as to make
something useful out of it and properly interpret the information. Sometimes, though, due to the nature of the
information coming in, the shortcuts cause misinterpretation instead. This is likely what cause optical illusions
to occur.
And
because there are many types of shortcuts the brain uses, there
are many types of optical illusions.
