In A Nutshell
When electrically stimulating the left hemisphere of an epileptic’s brain, doctors discovered that they could create a sinister shadow person for the patient much like the type of illusion a schizophrenic may experience. It’s that creepy feeling you get when you think someone is watching you or following you. Neurologists believe they can build on this knowledge to reveal how the brains of schizophrenics and paranoiacs conjure up these sensations.
The Whole Bushel
You’re alone. You get the strange feeling that someone is following you. Maybe you simply feel like you’re being watched. But when you look around, no one’s there. Is someone hiding or are you imagining things?
Even people without mental health problems can have fleeting moments of strange sensations. But for individuals who suffer from schizophrenia or paranoia, the experience is often much longer and more intense. Schizophrenics may feel like someone is mimicking their movements. Other mental health patients may feel as though they’re controlled by aliens or being persecuted in some way. Some people even believe that aliens have abducted them.
In the mid-2000s, doctors accidentally found that they could reproduce delusions in patients with no previous psychiatric problems. At University Hospital in Geneva, neurologist Olaf Blanke was trying to find the source of a 22-year-old woman’s seizures before she underwent epilepsy surgery. With dozens of electrodes implanted into the young woman’s brain, Dr. Blanke applied mild electrical stimulation, or shocks, to different areas of the brain to identify where seizures were triggered. He also wanted to know which areas controlled hearing, speech, or other brain functions that he didn’t want to disturb in surgery.
As each electrode stimulated a different area of the brain with a mild electrical current, the patient was asked how she felt. The procedure was fairly uneventful until the doctor shocked the woman’s left temporoparietal junction (TPJ), an area of the brain located approximately above the left ear.
Immediately, she sensed the presence of a “shadow person” behind her. She didn’t realize that it was just an illusion, an imagined double of her own body. She really felt as though someone else was there. “He is behind me, almost at my body, but I do not feel it,” she told doctors.
The creepy shadow person mimicked her bodily positions and actions. He lay beneath her when she was lying down and sat behind her when she was sitting. When the woman was instructed to lean forward and hold her knees, she felt a disturbing sensation of the shadow person hugging her. When she was asked to do certain activities, the shadow person attempted to interfere. For example, when she was holding a language-testing card in her hand, the shadow person tried to take it. “He doesn’t want me to read,” she said.
Fortunately, the effect was temporary for her. When the electrical stimulation stopped, the shadow person disappeared. Shadow people can also appear to people experiencing sensory deprivation, such as mountain climbers at high altitudes or sailors alone at sea. Patients with blood flow disruptions to their brains, such as those who’ve had minor strokes, may also perceive shadow people.
The young epileptic’s experience raises interesting questions about how our brains recognize our bodies and perceive “self.” The TPJ is associated with self-perception, which allows us to distinguish ourselves from the people around us. By processing sensory cues like sight, sound and touch, it helps us to understand how our bodies are positioned and how they relate to what’s around us. When the function of this area of the brain is disturbed, we may perceive two bodies rather than one, with the second mistaken for a stranger.
Schizophrenics often feel their bodies belong to someone else or that someone else is responsible for their actions. Frequently, they feel like they’re being followed or controlled or manipulated, whether by strangers or aliens. In some of these cases, hyperactivity has been noted in the TPJ. But schizophrenics often have much more complex delusions than the young epileptic did. They see and hear things all around them, not just in a shadow position.
Nevertheless, neurologists believe they can build on this knowledge to reveal how the brains of schizophrenics and paranoiacs conjure up these sensations. Perhaps it will even lead to more effective treatments for people suffering from these disorders.