The Remarkable Accuracy of Colour Perception: Lecture Response

    Last week I went to a lecture by Lorne Whitehead, who is a physics professor and professional engineer at UBC. The lecture was about new discoveries about colour processing in the eye and brain, and specifically the unlikely-seeming accuracy of colour perception.
I didn’t understand most of it, but I’ll tell about some of the interesting facts that I did get, and then hopefully you will understand them to.
    Trichromatic (colour) vision evolved as a way to see what things were made out of, or what was inside them. Our early human ancestors originally saw light in the UV range, as many birds and other animals do still. But as humans became more diurnal (awake in the day), it became more beneficial to see colour. It helps us judge what fruits to eat, decide when meat is done, tell how healthy people are… and many other things. This is pretty obvious.
    But something unexpected was how accurate our colour perception turns out to be. While most of our senses (smell, temperature, etc.) have around a 50% percent accuracy, the accuracy of colour perception is around 5%.So why is colour vision so accurate? Think about a banana. You can easily tell if it’s it’s good or not with one look- even though it’s colour barely changes at all.
    Another interesting thing Dr Whitehead mentioned was an answer to someone’s question at the end of the lecture. Someone had asked if he was worried about humans losing colour vision, since it wasn’t necessary for survival anymore, to which he answered no, but he said he was “very worried” about what screens did to us. Screens are always getting better, which often includes more vibrant colours and contrast, which he says is very bad for our eyes. According to him, it can take up to a week for our eyes to fully recover from viewing a contrasty screen. Luckily, we can easily avoid this problem; almost all screens have ways of adjusting the colour and contrast.
    Lastly, I want to show you an interesting image that Dr. Whitehead used in his slide show. It shows what the raw signal coming out of your eye looks like.
https://i.pinimg.com/originals/fc/ea/76/fcea76d986367493f568789540cc75b9.jpg
That is all you’re eyes actually see- anything else is a result of your brain’s processing.