Parents look around at our winner-take-all economy and unpredictable world and, quite understandably, get scared for their kids' future. Many react by signing their children up for activities or lessons, or constantly nagging them to study harder.

But all this frenzied preparation might be, in the best case, useless, or in the worst, counterproductive if it cuts into one of the few activities that science has shown again and again to correlate with intelligence in kids.

What's this miracle intervention? Simply making time to talk more with your children. 

More words means a higher IQ

Scientists have long suspected there is a connection between how many words a young child hears and their cognitive development, but earlier studies have all had methodological problems. Some, for instance, placed researchers in families' homes to record them. Wouldn't parents behave differently if they someone was sitting there watching, critics wondered.

A new study recently published in Developmental Psychology that followed 100 London families aimed to get around these objections by using small, unobtrusive recording devices placed on 100 preschool-age children to measure how many words the kids were exposed to each day.

When the researchers used software to analyze the recordings and then gave the children a series of cognitive tests, the expected pattern again emerged. The more words -- and more high-quality words -- a child heard, the more intelligent he or she was likely to be.

"Children whose parents used more words tended to do better in the cognitive tests," is the British Psychological Society Research Digest blog's simple summation of the results.

Don't neglect the parenting basics. 

This is only one observational study and the authors are clear that it can't prove causation. Maybe smart kids just push their parents to talk more. But there are plenty of good reasons to suspect that making the time to chat with your children helps them maximize their intellectual potential.

The longest-running child development study ever, which followed no less than 70,000 kids for 70 years, came to similar conclusions. Political and social factors, like adequate schools and support for parents, was crucial for kids' development, it found, but on the level of individual families, basic things mattered the most. One of the big differences between kids who thrived and kids who failed to reach their full potential was simply having parents who took the time to listen and talk to them.

If you're reading this, there's a good chance you're the type of parent who is deeply invested in doing well by your kids. You're likely in no danger of ignoring them. But that doesn't mean you're talking to them as much as you could be.

Concerned parents often crowd their kids' schedules with activities, sometimes crowding out old-fashioned dinner table conversation. Or maybe you spend more time looking at screens than you should and less time actively chatting with your children. If so, this latest study is a polite nudge to rethink.

Kiddie soccer and toddler clarinet lessons are all fine and good if your child enjoys them, but they're not essential for your child's intellectual development. Talking to their parents is. Make sure you're not neglecting this very important basic in the rush to give your child a leg up in life.