Neuroscientists at Sweden's Karolinska Institutet used a head-mounted display to give people the perceptual illusion of invisibility when they looked down at their body. Then they pretended to stab the person.
From Sci-News.com:
To demonstrate that the illusion actually worked, they would make a stabbing motion with a knife toward the empty space that represented the belly of the invisible body. The participants’ sweat response to seeing the knife was elevated while experiencing the illusion but absent when the illusion was broken, which suggests that the brain interprets the threat in empty space as a threat directed toward one’s own body.
In another part of the study, the scientists examined whether the feeling of invisibility affects social anxiety by placing the participants in front of an audience of strangers.
“We found that their heart rate and self-reported stress level during the ‘performance’ was lower when they immediately prior had experienced the invisible body illusion compared to when they experienced having a physical body,” Dr Guterstam explained.
"Neuroscientists Create Illusion of Having Invisible Body" (Sci-News)
"Illusory ownership of an invisible body reduces autonomic and subjective social anxiety responses" (Scientific Reports)