Many people are skeptical about the practice of hypnosis, but a new study shows those under a spell may not be faking it.

Researchers from the University of Sussex conducted a study, which found the effects of hypnosis to be involuntary. Their research adds to a growing body of literature that seeks to understand the science behind a practice that's often used in the medical world, but has also been included in the magician's bag of tricks.

Read: Does Hypnosis Work? Brain Function Changes Unconscious Parts Of The Mind, But Only For Some

Hypnotism, also referred to as hypnotherapy, has been used to reduce stress and anxiety, and to influence behavior changes, including bed-wetting and smoking.

In the small study, published in Psychological Science, researchers conducted an experiment on 18 people who were previously determined to be susceptible to hypnosis. All of the participants were assigned to do a series of tasks involving pressing a button either voluntarily or under a hypnotic command.

The subjects’ reaction times under hypnosis were then compared to the times it took when they chose to press the button voluntarily and when signaled with a string.

Under hypnosis, the participants believed they pushed the button nearly as fast as when they were prompted to with a string. Furthermore, study author Peter Lush claims the subjects, when under a spell, behaved in a way that would be hard to fake. He believes the hypnotic experience feels as real for the subject as it does for the observer.

“Our study was set up to ensure that this degree of shift in the reported time of events cannot easily be explained by participants wishing to conform to the demands of the task,” said Lush, in a news release. “The results suggest that people who experience involuntariness are genuinely experiencing changes in the sense of agency over their actions.”

Lush notes his findings don’t explain how the hypnotic experience occurs. Are the actions genuinely involuntary, or is the experience mind-altering, he questions.

“Our interpretation of the results is that hypnotically suggested involuntary actions are voluntary actions that are experienced as involuntary,” said Lush.

When under hypnosis, a person often feels calm, relaxed, and focused. Despite what you’ve probably seen in movies, your behavior is not out of your control, Mayo Clinic states. Additionally, a patient usually remembers what happened during their trance-like state.

See also: New Hypnosis Technique May Bring Brain Surgery Patients Psychological Relief During 'Awake Surgery'

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