There is an interesting article in The Princeton Packet here about neuroscientist Sam Wang, associate professor of molecular biology and neuroscience at Princeton University, who gave a lecture with various fascinating insights about human relationships:
"Our brains have the job of helping us survive in the world and fight another day,” he said.
On a common brain myth:"Dale Carnegie, the self-improvement pioneer, [made the] assertion that we use only 10 percent of our brain, which he ascribed to Mr.[Henry] James. Mr. Wang said...The truth is “you need every bit of your brain,”... “If you have a stroke you will find out, sometimes the hard way, that you use every bit of your brain,” he said.
Many of the things adults do to keep their brains sharp, including Sudoku and crossword puzzles, help your brain get better at those specific tasks but don’t have much if any broader benefit, Mr. Wang said. Instead, “physical exercise is one of the best things you can do,” to benefit your brain, he said....”There is a rule of thumb that things that are good for your heart are good for your brain,” Mr. Wang said.
... Although men and women are equally good at reading their own moods — whether they are in a good or bad mood — “everybody is better at reading women’s moods,” based on whatever signals women send out, Mr. Wang said.
“Eight hours of study is more effective spread out over two or three sessions than over one session.” And a good night’s sleep before the exam does help you better process all that studied information, he said.
...weighing in on the “nature versus nurture” question. It has been demonstrated that increases in IQ across populations do occur at a more rapid clip than evolution would allow for, he said, so nurture is important."
More information about puzzles of everyday life is here on one of his websites.
Sudoku is still fun, in my view, if you play an easy enough game to finish, and the more that it's played, the easier it is.