Can you improve your intelligence?

I just finished reading Dan Hurley's book Smarter: The New Science of Building Brain Power.  It was worth reading, but it is a prime example of TLDR.  It is much more efficient to read a quick blog post summarizing the results because there is a ton of irrelevant stuff in this book.  So lucky you, I am going to tell you everything you need to know in the next 2 minutes.

Basically Dan is a really good science journalist.  He goes around interviewing intelligence training researchers (and he picked the really good ones - good for him!!!).  He also tries the training systems out on himself.  He even attends a few academic conferences and watches the presentations.  And this is what he finds:

1. If you have specific deficiencies (due to autism, dyslexia, Downs Syndrome), then you can train on those specific deficiencies and overcome them to some extent.  This is great news for anyone with one of these conditions
2. You can delay the cognitive decline of aging by doing the more complex cognitive training methods.  This doesn't mean crossword puzzles (too bad, I love crossword puzzles).  It means the dual N-back test (the dual part is very important) or series of tests run by COGMED, Lumosity, etc.
3. You can improve specific skills by training on those specific skills.  For example spatial working memory or focused attention. 
4. But the evidence that these training tools help the typical person increase their overall intelligence is mixed at best.
5. If increasing your ability to focus your attention helps you learn better, then that could be something that generalizes.  Mindfulness training is one possible way.
6. Also, general fitness is important so do your exercise (aerobic and anaerobic, just in case).
7. There is a genetic trait that determines how often you switch among thoughts/tasks/strategies/goals.  Most people switch too early (ADD-like) or too late (obsessive-like).  This is related to your working memory capacity and to your brain's sensitivity to dopamine.
8. Higher fluid intelligence (the Holy Grail) can be characterized by creating larger chunks of these thoughts/tasks/strategies/goals, so whatever your switching trait is, you can do more with the ones you have in working memory at any given time.
9. Both the researchers who believe in intelligence training and those who believe we can't do it all believe that the 10,000 hour rule (see Malcolm Gladwell) is bunk.  There is a genetic component/natural talent, whether we like it or not.