Brainiac #3 What do blind people see when they hallucinate?

Charles Bonnet described this form of hallucinations in detail.
Bonnet's grandfather lost his sight almost completely by cataract. But the old man saw colorful patterns, animals and people on the walls. Sometimes this happens to people who become blind at a later age. Bonnet himself also got to see what he saw.
How is this possible? When your brain gets too little stimulus, the parts of your brain that are normally responsible for eyesight will start emitting signals. It looks like you're seeing something but in reality your brain creates images from your memory. Someone who becomes blind and uses drugs can start hallucinating and use the images from his memory. But what if you do not have any pictures/images in your memory?

The best known drugs causing you to hallucinate are mushrooms and LSD. Fully called LSD stands for Lyseric Acid Diethylamide. In mushrooms the hallucinating psychedelic is called Psilocybin. How these substances cause delusions is not exactly known. They both intervene in the making of serotonin in your brain. Serotonin influences your mood, appetite and sleep. It also plays a role in the way the brain interprets the surroundings. You see strange things because the processing of information from your senses is disturbed.

In the early 1960s scientists were experimenting with LSD. Researchers at The University of Chicago conducted a pilot in 1963. 24 volunteers of whom 4 were born blind were administered LSD. Most of the persons who lost their sight at a later age had visual hallucinations during the trial. They saw spots, colors and light. The 4 people who had never seen before in their life didn't experienced hallucinations in a 'traditional' way. However, it was striking that they hallucinated more often with other senses. They heard, felt and smelled al kinds of things that in reality were not present.

Even if someone who was born blind experienced sight during a trip and telling you about it, you never know what he means. He was never taught to describe an image. People who were born blind can sense light sensations. Press your fingers on your eyelids; this will stimulate your retina, it will make you see light and colored patterns. Blind babies often press their eyelids with their fingers. Probably to stimulate the visual center of their brain. For the brain this is very important. You must learn to see, as is evident from studies with young cats.

Researchers from American universities raised kittens in different environments in the seventies. The cats lived in a box with only vertical lines. The researchers held a stick vertically in front of the cat and they start playing with it. But when this toy was horizontal positioned they didn't do anything because they couldn't see the toy. For animals growing up in a cage with only horizontal lines the results were reversed. Those animals played only with horizontal sticks. Their brains were so affected that the cats could no longer learn to see anything else other than the lines they grew up with.

Want to hallucinate? With these products you can summon the pink elephants:
• LSD is made in the lab. It's on a piece of paper you can put on your tongue.
• Mushrooms produce Psilocybin. Eat them raw or make a cup of mushroom tea.
• Angel Dust of PCP is dropped on cigarettes.
• The Peyote is a cactus that creates Mescaline. You can eat it.
• Some toads have Bufotenin on their skin which you can lick off.
• Ketamine can be snuffed.
• Dried leaves of the Salvia Divinorum can be smoked in a water pipe.

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