MojoKid writes "Nintendo has quasi-acknowledged that its 3DS can cause headaches and should not be used by children under 7. The glasses-free 3D handheld gaming device launched this week. Meanwhile, new research commissioned by the Blu-ray Disc Association is trying to improve the health image of 3D. Its research shows that the brain is more attentive when watching a 3D movie than when watching HD or SDTV, making the movie a more pleasurable experience. The issue, doctors say, is that 3D works by tricking the brain into making you think you are physically moving in relation to your surroundings. But you aren't. So your inner ear is not experiencing the movement that corresponds to what the eyes are seeing. This doesn't normally happen in real life. No one would deny that 3D is more immersive; that's why people like it, particularly for gaming. But the question is ... does the brain love 3D or not? Answer: not really."