Psychological disorders caused by prolonged exposure to PC games are already a serious issue. In 2015, two Taiwanese men died from marathon gaming binges within three weeks of one another. Deaths have also been reported in China, Korea, the USA, and Vietnam. Excessive gaming reportedly causes problems with logical thinking and the ability to interact socially. In some jurisdictions it is classified as an addiction. In May 2013, the American Psychiatric Association (APA) proposed criteria for video game addiction in the Diagnostic and Statistical Manual of Mental Disorders, but shied away from including it as an official mental disorder.

This may be about to change. We now have the technology and soon the virtual worlds which will bring about a whole new canon of psychological and physiological problems. So far, users have reported dizziness and disorientation after just a few minutes in VR environments. In April last year, Sheryar Ali, Samuel Vaughn, and James Williams published a paper called “Physiological and Psychological Effects of Virtual Reality”. In it they report that users in VR environment show increased heart rate, dizziness as well as nausea (cue the Dramamine) in comparison to those who observed the game. It’s obvious if you think about it. You aren’t just playing a game, you are INSIDE another reality. Your body will react to gaming scenarios as if they were real.

Skeptics of virtual reality concern themselves with the negative psychological effects of virtual reality such as sensory conflict theory. One study defined sensory conflict theory as having the visual and vestibular systems at odds while in an immersive, virtual environment. The authors explain this as follows: “You are using the Oculus Rift and are in a moving car. You see the buildings pass by which signals by your visual sensory system that you are moving. But, you do not feel your hands turning the wheel, or your foot pressing the gas, which signals by your vestibular system that you are not moving.”

Efforts are under way to address this problem, notably by the Max Planck institute in Munich, Germany, which proposes a Star-Treck-style Holodeck to bridge the divide between perception and reality.

Much more worrying are the prospects for serious mental illness caused by long VR exposure. A study by Aardema et. al. showed that VR causes a significant increase in  dissociative experience (depersonalization and derealization), including a lessened sense of presence in objective reality as the result of exposure to VR. However, no one has yet studied the effects of long-term immersion in virtual reality, because of far we don’t have applications that allow for such tests. This is going to change in 2016. With the Hololens, the Oculus Rift and HTC Vive reaching consumers and companies rolling out VR applications from games to pornographic films, you can expect a slew of new medical conditions to make headlines.

Imagine, if you will, a widespread use of virtual reality in everything from social media to hard-core gaming. After all, why did Facebook buy the Oculus other than with the aim of turning Facebook into a VR world? Total immersion will cause disassociate disorders, behavioral changes and mood swings, especially in children. Parents are already hard pressed restricting computer time and watching out for the effects often violent games have on their offspring. Imagine your child spending hours or days not just playing Call of Duty, but actually inhabiting the CoD virtual world? Killing people in a traditional game does not seem to cause violent behavior in the real world (some experts disagree). But if the experience seems completely real, as it does in VR? How will that affect the development of young mind?

Some experts fear that once VR, AR, and MR really take off, you will encounter people for whom family, school or work life seems no more real than the time they spend inside Facebook-VR or their favorite game. VR will be used in education, social networking, research, to navigate file systems and software applications, in engineering and even medicine (doctors are using it for surgery) In other words, we may inhabit many different worlds for a large part of our existence. Will our minds cope? The realities will meld to a point where ‘gaming’ for example isn’t experienced as an activity but as an alternative reality, giving rise perhaps to schizophrenia and dissociative identity disorder, depression, anxiety, obsessive-compulsive disorders, eating and sleeping disorders. One article I found used the term VRIDD for virtual reality-induced dissociative disorders. Expect many more VRI-conditions.

The problems are not just psychological, Dr. Ling-har Kuo of National Taiwan University Hospital assures me. Day-long VR immersion will send conflicting signals to the body. If you eat in virtual reality, will you feel full? After how many hours in a VR world will your mind perceive it as 100% real and forget the world outside?

If gamers can already die of over-gaming today, how many deaths will occur once VR-gaming cafes are ubiquitous? This company is bringing full-immersion VR to 100 million gamers in China right now. Similar cafes are already open in Taiwan, Japan, and the US. HTC sees a great market here and hopes to set it’s Vive as the de-facto standard. But who will be responsible when hundreds of people “disappear” into virtual reality, lose all sense of time, or end up regarding home and school life as ‘artificial’ and their gaming personas as ‘real?’

Traumatic events are often the cause of the main types of dissociative disorders, i.e. dissociative amnesia, dissociative fugue, depersonalization disorder and dissociative identity disorder. Even in the real world people with such disorders are hard to diagnose and treatment is often difficult. With VR becoming a part of our lives, trauma may be caused by events inside the virtual space. Imagine being fully immersed for hours and then being shot or seriously injured. How will our minds and our bodies cope with that?

I am sure we will adapt to the new technologies somehow, but I also expect plenty of crazy stuff happening on the way there. One of the biggest challenges is for people to keep their social skills intact. One thing all industry insiders agree upon is that along with gaming, pornography will be a massive driver of VR adoption. In a world where you can “virtually” live and have sex with your favorite movie star or a perfect Prince Charming, the temptation for escapism is enormous.