More than 5 million Americans over age 50 are self-employed, AARP reports, and they account for 40 percent of the self-employed work force. But entrepreneurship poses unique challenges that can be very different from corporate life. I’m offering up tips from career coaches and experts in a Chicago Sun-Times guest op-ed article today. The piece is linked to a panel I’ll be moderating at the What’s Next Boomer Business Summit next week.

Call it the neuroscience of experience.

The Wall Street Journal explains in 1,800 words what you already knew: experience makes you more effective at what you do. Emerging research on aging brains points to improving brain function, WSJ reports:

… an emerging body of research shows that a surprising array of mental functions hold up well into old age, while others actually get better. Vocabulary improves, as do other verbal abilities such as facility with synonyms and antonyms. Older brains are packed with more so-called expert knowledge — information relevant to your occupation or hobby. (Older bridge enthusiasts have at their mental beck-and-call many more bids and responses.) They also store more “cognitive templates,” or mental outlines of generic problems and solutions that can be tapped when confronting new problems.

So . . . 50+ workers who feel they still have something of value to contribute in the workplace might be right—and employers pushing them out the door because they’re too expensive might be . . .dead wrong.

The research comes as some professions consider changing mandatory retirement rules. The U.S. Federal Aviation Administration is considering a rule change that would boost mandatory retirement age for commercial airline pilots from 60 to 65. Apparently this is good news for passengers; WSJ reports that notes while younger air controllers outperformed older colleagues in standard measures such as speed of response, older controllers did far better dealing with complex traffic problems. (Pilots’ unions oppose the change, which would slow the pace of promotion for younger pilots).

The legal profession is seeing some action in this area, too. A special committee of the New York State Bar Association recently called on law firms to end mandatory retirement policies for partners; the Equal Employment Opportunity Commission has filed age discrimination charges against Chicago-based law firm Sidley & Austin over forced retirement or demotion of partners. A good International Herald tribuneviewpoint piece on the issue is here.

Good news here for the companies hawking all those brain fitness products.