[ExI] quantia game
Dan
dan_ust at yahoo.com
Sat May 4 04:51:21 UTC 2013
On Friday, May 3, 2013 3:47 PM Anders Sandberg <anders at aleph.se> wrote:
> On 03/05/2013 19:07, Dan wrote:
>> Since Eugen mention tetrachromacy -- almost typed "tetrachromancy" :) -- did anyone see that report on mantis shrimp:
>>
>> http://www.sciencenews.org/view/generic/id/343056/description/Mantis_shrimp_flub_color_vision_test
>>
>> Strange that they have some of the hardware, but don't seem to be using it in the expected way.
>
> It is hard to test animals on vision.
And many other things, no?
> In Sönke Johnsen's excellent "The Optics of Life" he points out that in many
> domains we are very bad at figuring out what makes sense to animals, and
> this makes our experiments less able to tell us much. Mantis shrimp are
> *weird*. (they show up in almost every chapter as an extreme case)
I'll have to find and read Johnsen's essay. Thanks for mentioning it.
I imagine with testing animals, one has to have a model in mind and then try to find other ways to corroborate the model. It seems the mantis shrimp didn't live up to the expected model, which seems to tell us something.
>> I also wonder, given that color opponent theory, if there's any processing going on at
>> higher levels. (I might be wrong here, gotten mixed up on what I've read about this,
>> but I presume opponents happen at a higher level of processing than color discrimination.
>> Am I wrong? Maybe I also missed something...)
>
> It is likely the retinal bipolar cells that create the opponent
> signals, which are then transmitted via the optic nerve to the
> brain. So the color discrimination actually works on opponent colors
> (differences between red-green and yellow-blue, plus brightness)
> rather than the "raw" red, green and blue signals.
Actually, that does make sense, since, as far as I know, there aren't human examples of people with messed up opponents, such as red-yellow but still having full color (for humans) vision from, say, a neurological condition. Or are there?
Regards,
Dan
See my SF short story "Residue":
http://www.amazon.com/Residue-ebook/dp/B00BS3T0RM/ -- US
http://www.amazon.co.uk/dp/B00BS3T0RM -- UK
http://www.amazon.ca/dp/B00BS3T0RM -- Canada
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