I’ve been asked several times over the weekend for my opinion about the warning issued by a French health agency about children watching 3D media. Coverage of this seems to have been popularized by the BBC and other media sources in the UK, and has gone viral.
Interestingly a summary of the report from Anses, France’s environmental protection/health agency, was issued in June of 2014 but is just making the rounds now. If your French is good enough, here is the entire 132 page document. Perhaps tellingly, the front cover of the report features a young girl looking over the top rather than through her 3D viewing glasses.
If you have the time and inclination, I’d also recommend reading a paper on Stereoscopy and the Human Visual System by Marty Banks and colleagues at U.C. Berkeley. Here’s a relevant section that lends context to the Anses report about exercising appropriate caution regarding sustained S3D viewing with children under the age of 13:
It also remains to be determined whether there are any short- or long-term effects of prolonged, repeated exposure to the unnatural stimulus presented by stereoscopic displays. In adults, accommodation-vergence coupling is quite adaptable (Schor & Kotulak, 1986), and so there is a possibility that accommodation function may take some time to return to normal following prolonged viewing of stereo 3D media. Moreover, as the stereo 3D industry continues to develop, our use of stereo media will change from an occasional activity to an everyday one. The introduction of stereo computer games, in particular, will expose viewers to vergence- accommodation conflicts regularly for potentially long periods of time. We may need to be particularly cautious about long-term effects of vergence-accommodation conflicts on younger children because their visual systems are still developing (Rushton & Riddell, 1999). We know of no specific causes for concern at this time, but the research required to identify relevant issues has not yet been done. It is reasonable to assume that vergence-accommodation coupling exists because it is beneficial, and so one should be cautious when systematically disrupting its natural operation. Of course, the ZoC could be measured in children in the same way it has been measured in adults. Clearly, however, it would not be acceptable to carry out the long-term experimental studies that would be required to understand any potential long-term effects (although, ironically, young people may expose themselves to such a regime voluntarily). Thus, clinical, research, and industry communities should remain alert to the development of unwanted symptoms in users of stereo media.