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General Science => General Science => Topic started by: paul.fr on 01/06/2007 07:53:02

Title: Can we learn to see things the right way up when we're hanging upside down?
Post by: paul.fr on 01/06/2007 07:53:02
when you hang upside down, you vision is also up upside down. How long would you have to stop that way for your vision to correct itself, so you were seeing the "right way up"?
Title: Re: Can we learn to see things the right way up when we're hanging upside down?
Post by: xerai on 01/06/2007 09:34:26
Not quick enough, I'm afraid. Headaches, bleeding into the retinas, numbness in your legs, and, of course, fainting would get to you before your vision had a chance to correct itself.
Title: Re: Can we learn to see things the right way up when we're hanging upside down?
Post by: Seany on 01/06/2007 10:29:05
What.. If you stayed upside-down, you can correct your vision???
Title: Re: Can we learn to see things the right way up when we're hanging upside down?
Post by: xerai on 02/06/2007 13:58:36
You can purchase glasses that turn everything upside down, but I've never really looked into it. I think it takes about 2-4 weeks for your brain to train itself to see everything the original way. Of course, once you stopped wearing the glasses again, you would see upside down again.
Title: Re: Can we learn to see things the right way up when we're hanging upside down?
Post by: chris on 03/06/2007 10:06:58
Not quite. Although you can compensate for visual inversion (or shift of the optical axis by wearing prism glasses), you don't wake up one day and see the world the right way up again.

Instead the motor system re-tunes itself so that up becomes down and down becomes up, so you know to reverse what your eyes are telling you when you go to do something.

It takes a couple of weeks to re-learn to perform delicate tasks, but a gross compensation occurs very quickly (within minutes).

Chris
Title: Can we learn to see things the right way up when we're hanging upside down?
Post by: iko on 03/06/2007 10:26:07
Quote from: chris on 03/06/2007 10:06:58
It takes a couple of weeks to re-learn to perform delicate tasks, but a gross compensation occurs very quickly (within minutes).

Chris

It surely does!

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.aeronautica.difesa.it%2Fsitoam%2Fimages%2Fpan15070-2.jpg&hash=a7851e96084cecd9be0126e92899e262)
http://www.aeronautica.difesa.it/sitoam/images/pan15070-2.jpg
Title: Can we learn to see things the right way up when we're hanging upside down?
Post by: Quantum_Vaccuum on 02/12/2007 00:58:17
Quote from: chris on 03/06/2007 10:06:58
Instead the motor system re-tunes itself so that up becomes down and down becomes up, so you know to reverse what your eyes are telling you when you go to do something.
(within minutes).

Chris

wouldn't that mean that when the light comes in its just going straight cause it normaly would flip the image on the retena?
Title: Can we learn to see things the right way up when we're hanging upside down?
Post by: Atomic-S on 03/12/2007 01:35:04
I had a problem like this trying to learn to tie a necktie in a mirror; my brain was in reverse of what I was seeing. Took a while to get used to it.
Title: Can we learn to see things the right way up when we're hanging upside down?
Post by: adwkiwi on 09/12/2007 22:34:03
Quote from: Quantum_Vaccuum on 02/12/2007 00:58:17
Quote from: chris on 03/06/2007 10:06:58
Instead the motor system re-tunes itself so that up becomes down and down becomes up, so you know to reverse what your eyes are telling you when you go to do something.
(within minutes).
wouldn't that mean that when the light comes in its just going straight cause it normaly would flip the image on the retena?
Actually no. As far as the nervous system is concerned 'up', 'down', etc are just directions you sometimes move. None are especially privileged. When you are an infant one thing you need to learn is the relationship between where something is according to vision and where it is according to your hand. It turns out this is an active, ongoing process, and you can alter the mapping in the lab quite easily.

The moral of the story - neither vision nor action have privileged knowledge about the world, they just have information about it. Each set of information is used to calibrate the other, all day (the 'tuning' mentioned) every day, all the time. This mapping can, with some limits, be altered and relearned (the main limit is simply that the calibration that the world usually provides becomes preferred by virtue of habit).
Title: Can we learn to see things the right way up when we're hanging upside down?
Post by: geosandler on 08/07/2009 03:42:06
You have to practice a lot, but yes you can do it.