(MONEY Magazine) – Who hasn't gone to a meeting and completely blanked on the name of a co-worker? I gave the memo to...um...uh.... Suffering this kind of brain freeze might be considered cute when you're 28. But if you're 48 (or older), you are vulnerable. The boss may think you've lost your edge or even pass you over for promotion. Worse, your name may pop into her mind when layoffs come around. And you'll have nothing to thank but that mushy mass of gray-pink that crowns your spinal cord. It's a chilling fact: Our own brains may be our worst office nemeses. As we pass from adolescence to old age, our neurons lose some of their firing power--they just don't process stuff like they used to. What's your name, again? That said, there's hope for middle-aged minds. "How you live day to day makes a great difference in how your brain functions," says Daniel Amen, M.D., author of Making a Good Brain Great. Try these cross-training techniques, all aimed at improving your mental fitness.

Build Memory Muscle

The goal is to increase your memory's storage capacity, akin to buying more RAM for your mental computer.

• RECOMMENDED EXERCISES As you go through your day, try pairing a series of words you need to learn--say, the names of the people on your new client's sales team--with known visual images. For example, link names you must learn with celebrities' faces (Ann in marketing equals Jennifer Aniston). Or connect items on your grocery list with objects you'd see on a walk through your office ("I spilled milk on the stapler, put the eggs on the desk..."). Repeat the list or story a few times.

• HOW THEY HELP Your short-term memory stores five to nine items at a time for up to 30 seconds. By repeating a longer sequence, you force it to hold more for more time. And by linking the data with familiar images, you create a second way to catalogue it in long-term memory--now it's both a JPEG and a text file. All the better for remembering your to-do list.

Maintain Mental Agility

One of the raps against older employees is that they find it tough to keep up with new ways of working. The antidote: Keep learning--any kind of learning--constant.

• RECOMMENDED EXERCISES Make time to take a language class after work; sign up for advanced computer training; sit in on your child's saxophone lesson.

• HOW THEY HELP "Learning helps keep neurons firing and makes it easier for them to keep doing so," says Dr. Amen. "Idle nerve cells waste away." Most experts agree that acquiring new skills can open up inactive areas of the brain and increase the number of neural connections. Yet while it's clear that educational activities have an immediate positive impact on gray matter, the long-term effects are still a bit hazy. Even if you're only briefly boosting brain power, however, it can't hurt to take up, say, Spanish. You'll become more open to new challenges at work and you'll have a leg up on communicating with foreign clients.

Speed Up Recall

Periodically slowing down can help you more quickly retrieve information from the dusty corners of your subconscious.

• RECOMMENDED EXERCISES Use your lunch hour for yoga or meditation. Or just close your office door and take a nap.

• HOW THEY HELP Paradoxical but true: Decelerating your mind can increase the speed of recall. Stress and information overload create "noise" in active areas of the brain. Just as driving while talking on your cell is hazardous, making business decisions while distracted is also unwise. "Your memory becomes imprecise the minute you start producing cortisol and adrenaline, the stress hormones in the brain," says Kathleen Hall, founder of the Stress Institute in Clarkesville, Ga. "You can't properly think about strategic planning or what your numbers were last quarter." Clear your head and you may find you're faster at recalling the important stuff, like the name of the guy down the hall you gave that memo to.

Curtis Pesmen is the author of How a Man Ages and The Colon Cancer Survivors' Guide.

66% of older people who did brain-training activities showed significant cognitive improvement in one long-term study.

SOURCE: Seattle Longitudinal Study.