Brain Fatigue: Devices' nonstop stimulation may prevent learning

Standing in line in the grocery store? Check your smart phone.

Waiting for the next teller at the bank? Check your smart phone.

Working out at mile six of a 10-mile run on the treadmill? Check your smart phone.

It seems life's most mundane moments are now filled to the brim with information thanks to these tiny, ever-present hand-held devices. At the flick of a finger, the entire world is in your palm — all your e-mail, all your friends, all of the Internet.

Those times otherwise spent staring into space or lazily people- watching now are spent staring down at the illuminated screen of an iPhone or BlackBerry or Droid.

"I don't let it go, it's with me 24-7," said Modesto resident Arisbel Gutierrez, 17, of her BlackBerry. "When I go to sleep, I just put it on silent."

This seeming end to boredom as we know it is a good thing, right?

Well, scientists have found an unanticipated side effect to the nonstop cell phone checking: When people keep their brains busy with digital input, they are forfeiting downtime that could allow them to better learn and remember information, or come up with new ideas.

So smart phones are making us more stupid?

Don't tell that to the people tethered to their digital devices.

Oakdale businessman John Melo, chief executive of Century 21 M&M and Associates, has his entire family linked via iPhone. He said he checks his at least once every 30 minutes.

"To stay connected with friends, family, business, it doesn't get any better than my iPhone," Melo said while shopping in Modesto with his daughter Jillian, 11. Both stopped to check their iPhones before hitting the mall.

Melo has been a digital device junkie from back in the day, his first a Palm III PDA that in the pre-millennial age was a fancy desk calendar masquerading as cutting-edge technology.

He said letting go can be tricky, especially once you become dependent on the devices for continual updates.

"Sometimes it is hard to chill with family and friends if you hear it buzzing and you know you can always pick it up and take a peek," he said. "But the ups are far greater than its downsides."

He said the ability to connect with his family, check his e-mail anywhere, access information instantly and keep up to date with his business makes his iPhone 4 indispensable.

Still, at work, Melo said, he has noticed that his co-workers and business associates always keep one eye on their phones when talking to him. Split attention, it seems, is a side effect of information overload.

That bears out what University of California at San Francisco scientists have found in experiments with rats.

They discovered that when the rodents had a new experience, such as exploring an unfamiliar area, their brains show new patterns of activity. But only when the rats take a break from their exploration do they process those patterns in a way that seems to create a persistent memory of the experience.

The researchers suspect that the findings also apply to how humans learn.

"Almost certainly, downtime lets the brain go over experiences it's had, solidify them and turn them into permanent long-term memories," said Loren Frank, assistant professor in the department of physiology at the university, where he specializes in learning and memory.

He said he believed that when the brain was constantly stimulated, "you prevent this learning process."

At the University of Michigan, a study found that people learned significantly better after a walk in nature than after a walk in a dense urban environment, suggesting that processing a barrage of information leaves people fatigued.