Your Brain Constructs Your Reality
Brains don't get out much. Actually they spend all their time in the dark, surrounded by chemical and electrical signals (kind of reminds me of Dr. Frankenstein). Another thing, colours don't actually exist, they are simply a construction of the brain, in fact we don't ever need our eyes to see. Remember that flying dream you had last week? You were wearing a purple velvet jumpsuit and fell into the orange ocean, that turned into a strawberry daiquiri, (Ok so that was my dream) well your eyes weren't open were they?
Humans, (that's us), only see a small fraction of the stuff that's out there. Most of us can see a rainbow, which is simply the refraction of white light. The sky only looks blue, because this spectrum of light is somewhat short and is absorbed by gas molecules in the atmosphere, then scattered off. A sunset on the other hand, looks red, because the suns rays have to travel further to reach us; this results in more scattering of the shorter waves and the longer red waves reach our eyes. Indeed, a red rose only appears red to us, because it absorbs certain wave lengths and reflects others.
But while we can see the waves of the rainbow, we can't see radio waves, which are massively longer, but they are there and can be measured. Also consider red-green color blindness, the most common type of color vision deficiency, which due to a few genes, or damage to the cones in the retina, results in the inability to tell the difference between various hues of red and green. There are many varieties of 'colour' vision disorders however, like Monochromacy, where a person only sees in black and white. A cow on the other hand doesn't see grass as green because they lack colour receptors.
When you pat your cat, eat chocolate or listen to Gershwin, your brain only has chemical and electrical signals to work with. Remember it's stuck in the dark cave of your skull. Your brain even constructs your sense of time (yes it does). Think about watching your favourite TV program, when time seems to go very fast. But if you are waiting at the doctors office or have to study, each minute seems to crawl along like Sammy the snail.
Duck or Rabbit
My Wife and My Mother-in- Law
What do you see in the first picture a duck or a rabbit? What about the second, a young lady with a feather on her hat, or an old women wearing a scarf? How we perceive each part of a picture, depends on how we see the whole image. The petite nose of the young lady, is the wart of the old women. Or the young women's coat is perceived as a sumptuous fur, while the old women's coat, more of a rough wool. Our brains are pattern makers, trying to make sense of the world and even if the data is incomplete the brain is trying to find/make meaning. Look at the picture below, we see a floating white triangle, which doesn't actually exist.
Who are we Anyway?
Consider the famous case of Phineas Gage, who had been a sensible, hardworking family man until a tamping iron which was 3 feet 7 inches long and weighed 13 1/2 pounds went through his head. Gage after the accident, became a different man, swearing, rebellious, obstinate and impatient. Today we know that severe damage to the frontal lobe of the brain, will cause such personality changes.
Neuroscientists,and David Eagleman, examine, how brain injury, brain tumours or disorders such as epilepsy, can change personality, or our experience of life. Some patients, for example with temporal lobe epilepsy begin to see 'cosmic significance in insignificant events' and become 'egocentric' and 'pedantic'. Neurologist Oliver Sacks, researches patients, who when experiencing hearing loss, begin to have musical hallucinations. It seems that the brain wants imput and if deprived of it, may create whole symphony orchestras, or even a voice singing "God Bless America".
How Do We Know What is Real?
If we can't rely on our senses, because they may lie to us and brain injury, tumors or neurotransmitter dysfunction is capable of changing our behaviour, character or function, how do we know who we really are?