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Author Topic: Why do my eyes perceive colour slightly differently?  (Read 4872 times)

Offline Mazurka

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When I look at something closely I have noticed that my left eye (which is dominant) sees things slightly brighter than my right eye.  Why is this?

How could I quantify this difference?



 

Offline chris

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Re: Why do my eyes perceive colour slightly differently?
« Reply #1 on: 29/08/2012 00:09:49 »
There could be a difference in the lens and corneal optics between the two eyes; there may be a difference in the photoreceptor subtypes between the two eyes - the pigment genes for rhodopsin are on the X choromosome; there are multiple alleles for some of them; women can be a mosaic for the different alleles, meaning some parts of the retina see a different hue than others.
 

Offline CliffordK

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Re: Why do my eyes perceive colour slightly differently?
« Reply #2 on: 29/08/2012 00:49:00 »
Is this something new?  or something you just noticed. 

Cataracts, which often occur in the elderly can affect the vision in one eye worse than the other eye.
 

Offline RD

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Re: Why do my eyes perceive colour slightly differently?
« Reply #3 on: 29/08/2012 06:09:20 »
When I look at something closely I have noticed that my left eye (which is dominant) sees things slightly brighter than my right eye.  Why is this?

Quote
When someone accommodates to a near object, they also converge their eyes and constrict their pupils. The combination of these three movements (accommodation, convergence and miosis) is under the control of the Edinger-Westphal nucleus and is referred to as the near triad.
https://en.wikipedia.org/wiki/Accommodation_%28eye%29#Induced_effects_of_accommodation

If the refractive power was not the same in both eyes the pupil constriction which occurs when focussing on near objects would not be equal either. The pupil controls the brightness of the image.
« Last Edit: 29/08/2012 06:12:20 by RD »
 

Offline Mazurka

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Re: Why do my eyes perceive colour slightly differently?
« Reply #4 on: 29/08/2012 08:59:44 »
Thanks for the replies - Could a slight difference in accomodation be explained by surgical squint correction as a child?
 

Offline RD

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Re: Why do my eyes perceive colour slightly differently?
« Reply #5 on: 29/08/2012 19:29:10 »
... surgical squint correction as a child?

That could be the explanation for unequal brightness only when focussing on objects which are close.

When focussing on a close object, (say a 10 inches from your face), ones eyes converge, (go a bit cross-eyed).

The convergence may be a necessary condition to trigger pupil constriction in the near triad.

If one eye requires more muscular effort to make it converge because of a squint, or the surgery to correct it, this may be responsible for uneven (lack of?) pupil constriction in one eye when focussing close up.

You asked if this was measurable, a photo of your eyes when you are focussing on something close may reveal unequal pupils.
« Last Edit: 29/08/2012 19:32:51 by RD »
 

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Re: Why do my eyes perceive colour slightly differently?
« Reply #5 on: 29/08/2012 19:29:10 »

 

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