In a recent report, the Anses invites users of virtual reality to respect some good practices in order to limit the undesirable effects linked to this technology. If these are very often temporary and benign, the precautionary principle applies for some people.

What, the, risks, when, testing, virtual, reality?

Virtual reality is increasingly used in various fields, including video games. The user is immersed in a virtual world entirely generated by a computer via the wearing of a visiocasque. He can walk around and enter rooms, for example, by the movements of his body. Its growing use among the general public has led the Anses (French National Agency for Food, Environmental and Occupational Health Safety) to study the impact of exposure to this emerging technology and the possible associated health effects. Its report, published in June 2021, indicates that some adverse health effects have been sufficiently documented to allow its working group to highlight them, while for others, the lack of data in the scientific literature does not allow to draw a conclusion.

The Agency first recalls that its survey conducted in 2019 had shown that the average duration of a virtual reality session is more than one hour.

  •  Among adults, users are more often men (57%) with an average age of 40 years, from higher socio-professional categories and with a good command of technological tools.
  •  Among children, virtual reality is mainly associated with video games and a predominance of boys is also observed (55%), the average age being 12-13 years.

But what are the risks for those who engage in this practice? The Anses informs that if the possible long-term effects are not yet well documented, the short-term effects seem reversible and limited.

What is cyberkinetosis? What are the symptoms?

The main risk associated with exposure to virtual reality is that it can disrupt the sensory system and lead to symptoms such as nausea, dizziness, sweating, paleness, and loss of balance. These symptoms are grouped together under the name of "cyberkinetosis", which is the subject of the vast majority of publications. "It can appear very quickly after the beginning of the experiment (in less than 5 minutes). The possibility of appearance is very dependent on the content (roller coaster ride, or on the contrary calm landscape, ...), the visual field solicited (the wider it is, the more intense the symptoms can be), or the visual interface and the mode of interaction. ", explain the experts of the Anses.

Visual symptoms are the most common in cyberkinetosis and may include eye strain, migraines and headaches, blurred vision or dry eye sensation. These disappear within minutes or hours. Following a session, a temporary modification of sensorimotor and perceptive capacities can also appear, which alters manual dexterity or the ability to orientate one's body.

A device used by virtual reality may also be involved: light-emitting diode (LED) screens. Potentially rich in blue light, they can disrupt the biological rhythm (delayed sleep, sleep disturbance ...) when viewed in the evening or at night. ", notes the Anses.

Continuing research to determine the possible long-term effects

In addition, it invites people prone to epilepsy to be vigilant since exposure to the light emitted by these LED screens (flashing sometimes imperceptible by the eye) can trigger seizures. In general, the Anses stresses that the intensity of all these effects "depends on the exposure devices (interface) and the content offered, but also on the individual sensitivity of each person. "

As for the adverse effects for which it is not possible to conclude, the Agency mentions long-term disorders, for example musculoskeletal disorders. Thus, "very few data are available on the possible neurological consequences or the effects on development, these deserve to be further investigated," she notes.

How to prevent these harmful effects of virtual reality?

It is possible to avoid these effects by adopting a few good habits.

  •  Stop as soon as symptoms such as nausea, dizziness or sweating appear.
  •  It is also advisable to observe a rest period after a session. "The body makes a significant effort to adapt to the virtual world with which it interacts, which can cause some fatigue. It is therefore important to allow an hour or two of rest before resuming an activity requiring high concentration, such as driving a car, for example," says the Anses.
  •  To limit the effects of blue light, sessions two hours before bedtime should be avoided, especially for children and adolescents who are more sensitive.
  •  Finally, if no major health risk is mentioned in its report, the Agency wishes that the use of virtual reality is to be avoided for people with epilepsy or those identified as sensitive: pregnant women, people suffering from motion sickness, with balance problems or prone to migraines.

Its experts point out that one field of application of virtual and augmented reality technologies has not been taken into account in the report: the therapeutic framework. However, it is through this that it would be possible, in the coming years, to better understand the "mechanisms at play during their use, which could help identify harmful effects in mirror not yet documented or not yet considered," concludes the Agency.