When a Stanford University researcher asked her to step off, she wouldn’t do it.
In reality Ms. Bell was walking on a carpet with a virtual-reality headset strapped to her face. “I knew I was in a virtual environment,” she said later, “but I was still afraid.”
The psychological impact of lifelike virtual experiences is just one of the challenges for virtual reality, a technology that might finally have its commercial moment in 2016—after decades of hype.
Samsung Electronics Co. and Google parent Alphabet Inc. recently have released virtual-reality headsets that use smartphones as the screen.
And, in coming months, Sony Corp. , HTC Corp. and Facebook Inc. ’s Oculus unit plan to release higher-end headsets that promise to immerse users in experiences that seem to be all around them.
Meanwhile, tech companies and media titans such as Walt Disney Co. and 21st Century Fox are developing content for the headsets, including interactive short films, courtside views of pro-basketball games and popular videogames such as “Minecraft.”
The technology also is expected to be one of the main draws this week at the Consumer Electronics Show in Las Vegas.
Beyond the common issues facing new technologies, such as whether consumers will pony up hundreds of dollars for another device, virtual reality is grappling with questions about how it affects a user’s body and mind.
The experience can cause nausea, eyestrain and headaches. Headset makers don’t recommend their devices for children.
Samsung and Oculus urge adults to take at least 10-minute breaks every half-hour, and they warn against driving, riding a bike or operating machinery if the user feels odd after a session.
Apart from the physical effects, Stanford University professor Jeremy Bailenson says his 15 years of research consistently have shown virtual reality can change how a user thinks and behaves, in part because it is so realistic.
“We shouldn’t fathom this as a media experience; we should fathom it as an experience,” said Prof. Bailenson, who also co-founded Strivr Labs Inc., which helps football players relive practice in virtual reality.
The psychological unknowns are prompting some backers to suggest setting standards for content. “We have to be very careful,” said Alex Schwartz, chief executive of maker Owlchemy Labs. “Scares in VR are borderline immoral.”