Last week I was introduced to an intriguing little brain game that could very well prevent Alzheimer's disease, with the nice side effect of helping to save the world.  The game was demonstrated no less than three times by a commenter on a previous article reading between the lines of some recent science-related news.

What is this new Alzheimer's-busting miracle brain game?  Before laying out rules, let's look at an example from the comments: "To opponents who insist no pollution can change the atmosphere, it's important to make the example of inserting 'taxes' for pollution and 'economy' for atmosphere."  If you're an economic liberal, invert that.

Do you see what Hank did there?  Let's try another one: "The Union of Concerned Scientists is an advocacy group that spends more in one year than Exxon spends in eight", so if anything Exxon spends money to support is invalidated, then we can't believe anything the UCS spends money supporting either.

Got the game yet?  You take an argument that viscerally appeals to you, and then, keeping the logic the same, morph it into an argument that makes you uncomfortable.  Does the argument for your favored viewpoint still seem as strong?  Does the viewpoint you don't like gain a bit more credibility?  Maybe not, maybe so, either way you're strengthening your brain.

Confirmation of preexisting beliefs is mentally rewarding.  But it's not challenging.  A mental challenge comes from novelty – from thinking about things in a new way, or from a different point of view.  And new research (or see a summary) suggests that people who challenge their brains can not only prevent dementia, but they can also prevent the physical manifestations of Alzheimer's disease – tangled protein deposits that invade the brain.*  The key, in the study, was a lifelong habit of learning and exercising the brain.  So by playing this little argument-swapping game, you challenge your mind and ward off dementia.**

Another example:
  1. Some scientists think growing genetically modified salmon would cause net harm to ecosystems if not done right, so we should never allow any GMO fish.
  2. Some economists think addressing climate change would cause net harm to economies if not done right, so we should never enact any climate policies.
Did you feel an urge to read past that last example without really stopping to consider it?  Did you immediately label the argument you don't like as dumb, and read on so my next point would push it from your mind?  If so, that feeling of unease you got is called a mental challenge, and that is how this ties back to Alzheimer's disease.

Of course, you won't end up changing your viewpoint every time you play our game, nor should you.  Some arguments really are better than others.  But when that's the case, by forcing yourself to honestly figure out why the other argument doesn't make sense, you'll be working out your brain.  This, by the way, is how a good scientist thinks.  The more intuitively appealing an argument feels, the more careful a good scientist is to examine it from all sides.

If you want to put rules to the game, try this.  First Rule: If you read something that either makes you feel 100% vindicated in your beliefs, or makes you 100% disgusted that someone could argue such a point, then don't talk about Fight Club then you're doing it wrong.

And as for saving the world?  Well, could you really argue that we wouldn't be better off with fewer dogmatic ideologues, of whatever stripe they may be?***

*Caveats: This study has one of those correlation/causation issues.  If you start out with a healthier brain, could that make you more likely to be mentally active, while independently helping you avoid Alzheimer's?  Also, the study used a questionnaire to determine lifetime mental activity, which, as measures go, is not quite ideal.  The authors report an expected error for the survey, but they don't appear to propagate that error forward when determining the significance of observed trends, which would have made a more thorough analysis.  See how I'm playing the game?

**Ask your medical professional if this game is right for you.  Your results may vary.  Side effects may include annoyance of those around you.  Warning, beverage may be hot.  Dammit Jim, I'm a scientist, not a doctor.

***No, really.  Could you argue that?  Come on, remember to play the game!