Can't quite remember what you were looking for on the computer? Not sure what that person's name is?

A study in the journal Neurology reports that cognitive problems are on the rise, especially among younger people. Looking at 4.5 million survey responses, researchers found that almost 10 % if those under age 40 said that physical, mental, or emotional conditions cause them serious difficulty concentrating, remembering, or making decisions.

That's up from 5% a decade ago. And for all ages, reported cognition problems rose from just more than 5% to 7% of people surveyed.

What accounts for this? There are some intriguing things that you can control.

Research in the journal PLOSGenetics shows that a high-fat diet impairs intermediate memory by making it harder for the brain to clear out debris (a process called autophagy) that’s clogging up your thinking process.

In addition, a study in Scientific Reports outlines why you may have a hard time concentrating: overexposure to all kinds of digital input. It turns out such exposure can actually thin your brain's cerebral cortex, which handles perception and memory.

Want three easy ways to strengthen your brain and have fun?

1. Get out into nature for a phone-free walk at least three times a week.

2. Eat a plant-based diet without highly processed foods, red or processed meats, or added sugars.

3. Find a passion and a sense of purpose and dive into it. (Gardening? Volunteering? Swimming? Anything will do.)

For more than 30 other ways to keep your brain healthy for a lifetime, check out 4YOUngevity.com.