Short answer: No, but online worlds can really stress you out.
By Daniel Engber

Virtual environments almost certainly induce genuine anxiety, says Grainne Kirwan, a psychologist who specializes in cybercrime at the Dún Laoghaire Institute of Art, Design, and Technology in Ireland. For example, your physiological and emotional responses to entering a dark alley in a video game may be comparable to those you’d have in a similar real-life situation. “But would it be to the extent of initiating post-traumatic stress disorder? That hasn’t been demonstrated,” Kirwan says.

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