Jimmy Sioris grabbed his phone last week and dialed a number. Then he started to read an e-mail, "and within about 5 seconds I forgot who I called or why I called them," he said. "The phone is still ringing, and I have no idea who is going to pick up."

Voice mail averted a seriously awkward conversation, because the person Sioris was calling didn't answer.

A "senior moment"? Hardly. Sioris is 30.

Turns out that senior moments are not just for seniors anymore. Truth be told, they never were.

"Everybody's done that -- walked out of the house and forgotten something," said Susan McPherson, an associate professor of neurology at the University of Minnesota. "I guarantee you did it when you were younger. When we age, we just do these things more frequently."

We also worry about them more. In McPherson's version of the stages of an inattentive life, "In your 20s, you say, 'I am a space cadet.' In your 30s and 40s, it's, 'Man, am I stressed.' In your 50s, you go, 'Huh,' and in your 60s, you go, 'Uh-oh.'"

The good news, at least for those under 65, is that these unmindful moments are rarely symptoms of a disease such as Alzheimer's, which primarily afflicts those over 70. They can be signs of cognitive impairment but usually are just part of the brain's natural aging process -- "Your thinking does slow a bit in each decade of life," McPherson said -- or something physical.

"If you're stressed and sleep-deprived, your memory is not going to perform at your best," said Leah Hanson, director of HealthPartners' Alzheimer's Research Foundation. "It's not something wrong with your brain. It's your body."

The memory also might be affected by "thyroid disease, anemia, medications, psychiatric problems, depression," said Dr. Ronald C. Petersen, director of the Alzheimer's Disease Research Center at the Mayo Clinic. "Sleep apnea can lead to reduced cognitive efficiency."

So can multitasking, especially as we get older.

"Instead of juggling six balls like you did in your 20s and 30s, maybe you can only do two or three balls when you're 60," McPherson said. "It's not memory per se; it's attention."

Basically, the experts say, middle-aged people need to pay more attention to the practice of paying attention.

"It's easier to have a senior moment if you're not giving full attention to what your spouse is saying," Hanson said.

When to be concerned

Certainly some people, no matter their age, "are more prone to [brain cramps] than others," McPherson said. "If somebody has always been the absent-minded professor, that's who they are. He's always misplaced his keys and never known where his glasses are when they're sitting on top of his head."

For the rest of us, though, when does the rise in forgetful incidents become cause for concern?

"When you start having trouble with forgetting on a regular basis," McPherson said, "or when you start having trouble with a regular task, like taking medication. Or maybe you're having trouble learning something new, and that might be learning that your hair appointment day is Thursday rather than Wednesday."

Often, it's a family member who notices that "you're not clicking on all six [cylinders] like you used to," Petersen said.

For those concerned that they are moving beyond "nuisance forgetfulness" into what's called "mild cognitive impairment," Petersen said, "the place to start is your personal physician, who knows you well. And if he or she says this is a change, they might prescribe a treatment or refer you to a specialist."

Not many proven tricks

For those afflicted only with garden-variety "Why did I go on the Internet again?" scenarios, there is good news and bad news.

First the bad: There are few, if any, proven tricks or triggers to help us in the moment. Petersen recommends "a little more attention on the input side." Minneapolis psychologist Mindy Mitnick visualizes "what I was doing when I made the decision to do something," that it is all about how we encode information. McPherson had a less quiet approach: "If you want to remember something, say it aloud."

Now the good: There are promising drugs on the horizon. In the meantime, because the increase in "brain farts" is tied to aging, activities that keep our brains and bodies fit can help slow the inexorable slide (see box on E1).

"My adage is, 'You can teach an old dog new tricks. You just have to teach them longer,'" McPherson said.

And some "dogs" probably will never learn.

"I'll be driving on Hwy. 100, and all of a sudden I'm in Edina and go, 'Wait a minute, I wanted to go to Uptown,'" Sioris said. "I never know where my keys or my wallet or my phone are. I'm just über-scatty."

Bill Ward • 612-673-7643