Hallucinations When Covering Your Eyes For Several Hours
In a 2004 study, scientists from the Harvard Medical School blindfolded a group of 13 people that they would have to stay blind for five days. Throughout these 96 hours, these people reported on their experiences with the help of a recorder. The selected subjects were men and women between 18 and 35 years old with no medical history of cognitive dysfunctions, psychosis or ocular pathology.
None of these people took medication. The results indicate that complete deprivation of light above the eyes is sufficient to produce visual hallucinations in a few hours.
Study data
During this experiment, 10 of these 13 blindfolded people (77%) experienced visual hallucinations These strange images varied in intensity and complexity, some of them consisting of simple points of light and others of figures, such as a light Elvis Presley. Furthermore, none of these hallucinations referred to past experiences, they were new images.
Some examples:
Subject 1 (woman, 29 years old). She experiences a single hallucination, 12 hours after starting to wear the bandage. It occurs while in front of a mirror, and consists of a green face with big eyes. She is very scared by this vision.
Subject 5 (woman, 29 years old). During the first day she sees circles of light, an image that will be repeated throughout the week. On the second day she has the sensation of seeing her arms and hands moving and leaving a trail of light when she really moves them.
Subject 6 (man, 34 years old). He reports numerous hallucinations experienced while listening to the Mozart’s Requiem : the outline of a skull turning until it is facing the subject. On another occasion, also listening to the Requiem, she sees the silhouette of someone wearing a kind of ceremonial mask and headdress. This person has his face turned upside down and his mouth open. In a third audition of the same piece of music, he sees an older woman with a very wrinkled face and a threatening look. She is sitting in an airplane seat and she is wearing a red eye shield similar to the one worn by people who have to protect themselves from X-rays. Then, this person’s face takes the shape of a mouse’s face. Throughout the days the hallucinations continue, some of them with a stroboscopic effect.
Subject 8 (woman, 20 years old). At 12 hours she suddenly begins to experience hallucinations. Some consist of figures that transform, such as a butterfly metamorphosing into a sunset, into an otter, and finally into a flower. She also sees cities, lions, and sunsets so brilliant that she “can barely look in her direction.” All these hallucinations have movement. She places much emphasis on the beauty of some of these apparitions: “sometimes they were much prettier than anything she had ever seen…I wish she could paint.”
Subject 9 (man, 27 years old). See flashes of light during the first 24 hours. He later reports that he sees glowing peacock feathers and buildings of light.
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 the brain’s nervous connections, which tries to adapt to the lack of light. This is a process that may resemble that which causes phantom limb syndrome in people with amputated limbs.
