h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

There is the old saying that all cats are grey in the dark. In low-light conditions, our eyes switch from colour vision to seeing things in black and white. I am curious what happens then if you hallucinate in the dark. Would the hallucinations be in black and white too, even though the eyes are not actually involved? I figured at least some of the people on h2g2 might have experience with hallucigenics. Did any of you ever notice if the light around you affected what you saw?

Hello Xanatic
I have good night vision and colour is drained from the world it is shades of grey. Highi vision colour shift is very marked when street lights are involved yellows, greens and blues are added to the mix (depending on the type of light). Car headlights are surprisingly colour accurate though not 100℅.

This effect can be seen on photographs taken in various levels of darkness.
Cats may well be colour blind as they seem to have no colour sence at all smell rules.

Colour vision is not as important to a hunting anima. The only example I can offer is this. Colour blind servicemen in WWII could see camouflaged emplacements that were invisible to those with "normal" vision.


Hope that helps

Not really, no. I was asking about hallucinations.

The simple answer to that is yes police incodent records support this.

Yes to which part?

The strongest evidence I've seen for color vision with cats is that they gravitate to backgrounds that match their own color.

Blending in to the background is a decided advantage for an ambush predator.




On hallucinations, the phenomenology is related to dreaming.*!

There are some significant studies that suggest there may be a gender related bias, women more prone to dream in black and white, men more prone to dream in color.




The most common type of classical hallucination is the hypnagogic hallucination, one in which something dreamed on the moment of waking seems momentarily real.

Reports relating to drink and substance abuse the substantial majority are monochrome.

Even in reports from paranormal investagations (if ghoasts are a class of hallucination) there is little colour, unless a coulur is expected eg a red coat on a solder.

Yes Xanatic, hallucinations in the dark can be in colour. They can be in colour if you close your eyes, too; strong, intense colours.

I had a lot of migraines in my teens. They were accompanied by strobe-like visual fields. I would lie in bed in the dark until they passed. The colors were intense.