Image by jonycunha via FlickrADHD can really be a vision problem relating to depth perception and 3D vision.
According to Vision Help,, "treatable binocular vision problems (like convergence insufficiency) causes poor attention, concentration and reduced ability for near-centered visual tasks, such as reading and paper pencil activities." These vision problems can be misdiagnosed as ADHD because a person won't sit still while doing close-up work such as writing or drawing.
Apparently, a lot of the population has problems with 3D vision. It is estimated that 10-15% of the population have problems with 3D vision. As 3D technologies in movies and TVs become more prevalent, companies analyzing these industries are noticing problems in selling such devices due to eye discomfort.
A Blogger, Mark Schubin cites a November 2009 report from PricewaterhouseCoopers (PwC), “Eyes Wide Open: 3D Tipping Points Loom.” The report notes that the top two factors that could limit adoption of 3D technology are that approximately 20% of the people who attended a 3D movie didn’t like the experience, citing issues such as eye fatigue and discomfort of the eyeglasses, and about 5% of people are ’stereoblind’. The full report can be downloaded here:
Vision Help has a nice 5 part series on 3D vision written in a manner that the lay person can understand the issues are with 3D vision.