Actually, this post's title oversimplifies the story. It should read, "3D Is Bad For Your Brain Because Roger Ebert And The Guy Who Edited Captain EO Say So." I keed, I keed -- both film critic Ebert and uber-respected editor Walter Murch make a strong argument about why it's stupid to pay top dollar for movies basically designed to give you a splitting headache.

In a recent column for the Chicago Sun-Times, Ebert describes all 3D movies as "inferior and inherently brain-confusing," then lets Murch do the heavy lifting. According to Murch, "600 million years of human evolution" have not prepared our brains to look at 3D, which is why you paid $35 to see Tron: Legacy in IMAX MEGA COOL 3D and all you left with was a server farm-sized headache:
The biggest problem with 3D, though, is the "convergence/focus" issue. A couple of the other issues -- darkness and "smallness" -- are at least theoretically solvable. But the deeper problem is that the audience must focus their eyes at the plane of the screen -- say it is 80 feet away. This is constant no matter what.

But their eyes must converge at perhaps 10 feet away, then 60 feet, then 120 feet, and so on, depending on what the illusion is. So 3D films require us to focus at one distance and converge at another. And 600 million years of evolution has never presented this problem before. All living things with eyes have always focussed and converged at the same point.

After illustrating his point with weird pictures of blurry and not-so-blurry salt shakers, Murch makes the inevitable your-brain-is-like-a-computer analogy:
So the "CPU" of our perceptual brain has to work extra hard, which is why after 20 minutes or so many people get headaches. They are doing something that 600 million years of evolution never prepared them for. This is a deep problem, which no amount of technical tweaking can fix. Nothing will fix it short of producing true "holographic" images.

Like most of the problems we face today, the solution is ultimately "holograms."

Is this definitive proof that 3D "doesn't work and never will," as Ebert claims? I would argue that as Americans, we watch things that are bad for our brains all the time. Also, as long as studios can keep inflating their prices so an aggressively terrible movie like The Last Airbender is ultimately considered a hit, get ready to take a lot more Advil, movie fans.