In an attempt to understand what it’s like for a schizophrenic person, CNN’s Anderson Cooper tried a schizophrenia stimulator.

Cooper put on earphones and heard voices talking to him as he tried to perform simple tests and walked around New York City. The series of tests involved writing, remembering numbers and words, folding an origami boat, answering questions a patient in a mental hospital would be asked, and other tasks.

He described his experience as an “unpleasant experiment,” and said:

It’s incredibly distracting on the street to have somebody talk in your head. It makes you feel completely isolated from everyone else around you. You don’t want to engage in conversation with other people, you kind of find yourself wanting to engage in conversation with the voices in your head because they’re constantly being really negative and talking to you and everything they’re saying relates to things you’re actually doing.

The experiment was developed by clinical psychologist and researcher Pat Deegan, who was diagnosed with schizophrenia as a teenager.

According to the National Institute of Mental Health, the exact cause of schizophrenia is unknown, but experts think it's caused by several factors — genes and environment, and different brain chemistry and structure.

Approximately one percent of Americans suffer from schizophrenia. In addition to hearing voices in your head, other signs and symptoms include smelling and feeling things no one else can smell or feel, delusions, lack of pleasure in everyday life, lack of ability to begin and sustain planned activities, and speaking little, even when forced to interact.