In a 2004 study, scientists from Harvard Medical School blindfolded group of 13 who should remain blind for five days. Throughout these 96 hours, these people reported on their experiences using a tape recorder. The selected subjects were males and females aged 18 to 35 without a medical history of cognitive dysfunction, psychosis or eye pathology.
None of these people were taking any medication. The results indicate that total deprivation of light on the eyes is enough to produce visual hallucinations In few hours.
During this experiment, 10 of these 13 blindfolded people (77%) experienced visual hallucinations. These strange images varied in intensity and complexity, some consisting of simple points of light and others of figures, like an Elvis Presley of light. Moreover, none of these hallucinations referred to past experiences, they were new images.
subject 1 (Woman, 29 years old). You experience a single hallucination 12 hours after you start wearing the bandage. It performs in front of a mirror and consists of a green face with large eyes. She is very afraid of this sight.
topic 5 (Woman, 29 years old). On the first day, he sees circles of light, an image that will repeat itself throughout the week. On the second day, she has the sensation of seeing her arms and hands move and leave a trail of light as she moves the real ones.
subject 6 (Male, 34). He reports many hallucinations felt while listening to the Mozart Requiem: The outline of a skull turning to look at the subject. On another occasion, also listening to the Requiem, he sees the silhouette of someone wearing some sort of ceremonial mask and headdress. This person has his face turned and his mouth open. In a third audition of the same piece of music, he sees an elderly woman with a very wrinkled face and threatening gaze. She sits in an airplane seat and wears a red eye protector similar to the one worn by people who need to protect themselves from x-rays. This person’s face then takes on the shape of a mouse face. As the days go by, the hallucinations continue, some with a strobe effect.
topic 8 (Woman, 20). At 12 o’clock, he suddenly begins to hallucinate. Some involve transforming characters, such as a butterfly that transforms into a sunset, an otter and finally a flower. He also sees cities, lions and sunsets so brilliant that “he can hardly look in your direction.” All of these hallucinations have movement. He puts a lot of emphasis on the beauty of some of these appearances: “sometimes they were much more beautiful than anything I’ve seen … I wish I could paint.”
subject 9 (Male, 27). See flashes of light for the first 24 hours. He later reports that he sees resplendent peacock feathers and light buildings.
All hallucinations ceased when the bandage was removed or a few hours later. These experiences can be explained as the result of a restructuring of nerve connections in the brain, which tries to adapt to the lack of light. This is a process that may resemble that produced by phantom limb syndrome in people with amputated limbs.