Image: Senior man sitting at desk with computer © Andersen Ross, Brand X Pictures, Getty Images

After Ailika Thomas woke up from a snooze, her husband brought her coffee in bed. It was 7 p.m., and the 73-year-old was facing a long, moonlit drive from her rural Indiana home to Chicago; Dean wanted to make the journey as easy as possible for his wife. As she dressed, he warmed the car (a red Buick named Carmen) and stocked it with snacks -- containers of sugar peas, blueberries and her favorite, raw turnips. When Ailika emerged from the back door in a pink-and-white pants combo accompanied by her two Yorkshire terriers, Dean gave her a warm goodbye kiss and made her promise to call at journey's end.

It was a touching scene, but a familiar routine: Thomas' destination was her job. Five nights a week, she drives 90 minutes each way to work the midnight shift as a research supervisor for a big company downtown.

Thomas can't afford to retire. She's not complaining. The job keeps her connected, the benefits are generous, and there's still time to volunteer at downtown theaters and enjoy camping trips with Dean. But the commute! Sometimes, even the latest Dean Koontz thriller on tape can't keep her awake. She mists her face with a water fan, gulps 5-Hour Energy shots (bought by the case at Costco) and yells in the car. When the urge to nod off proves irresistible, she pulls off the interstate and naps in a supermarket parking lot.

Some might suggest that after 56 years in the labor force (she got her first full-time job in 1956, working for Encyclopaedia Britannica) and nearly two decades at the firm, it's time for Thomas to take it easy. But employers in nearby Michigan City don't pay nearly as well, and good luck finding a new gig when you're 73. Ask how long she'll continue, and Thomas says it's not her call: "I don't know how long God's going to let me live."

Retirement deferred

Commutes like Thomas' might be rare, but working well into one's eighth decade is a scenario that has become -- seemingly overnight -- relatively commonplace. For millions of workers, retirement has been delayed for years; others say they may never retire. Thanks to the nation's massive asset meltdown -- sagging retirement accounts, plunging property values -- an enormous swath of the population has had to redefine life paths. Older folks who assumed they'd be retired by now are struggling with the need to work long after the passion (not to mention the brain and the body) has started to fade.

The result of all this turmoil is a little-noticed but profound shift in the workforce. Some academics say we may well be reverting to historical norms, returning to pre-New Deal conditions in which most Americans had to work until they, well, dropped. The number of working people over age 65 reached an all-time low in 2001, when just 13% held jobs. Now that rate is rebounding, and fast; last summer, it hit 18%, a level not seen since President John F. Kennedy faced the Cuban Missile Crisis.

Of course, plenty of folks still have enough money to retire comfortably. But many boomers, facing a bipolar stock market and a pathetic return on their savings, feel deeply insecure; in one recent Associated Press survey, one in four predicted they'd never be able to retire. And between those two extremes, millions of workers in their 50s and 60s have quietly given up on the dream of an early retirement or the launch of an "encore" career. Instead, they're resigned to meeting the new demands of a work world they thought they'd bid farewell to. Facebook and LinkedIn? They were supposed to be playthings for the junior executive. Brain exercises? They were pitched as preventive medicine for senility, not a job requirement. Cosmetic surgery? Laughable -- until your career depends on it.

Labor experts say this first wave of delayed retirees will face the biggest challenges. They weren't prepared for the sharp reversal in expectations, or the difficulties of working while elderly -- nor were their employers. But for better or worse, this group is blazing a trail that subsequent generations of workers may wind up walking.

A relatively new concept

The decades-long retirement is actually a relatively new invention. In the early 1900s, nearly 80% of Americans over the age of 65 had jobs. Folks expected to work for as long as they lived, says Dora Costa, an economic historian at the University of California, Los Angeles, and they'd generally stop laboring only if they became too ill or frail to keep going. The average retirement lasted three years. That began to change, of course, with the introduction of Social Security and private-sector pensions -- both designed to free older workers from the need to choose between work and starvation. By the latter half of the 20th century, longer life spans meant people could count on living well past retirement age, and an evolving financial-services industry was pitching products like annuities to help people fund a long retirement. The result: By 2007, right before everything went to hell, the average retirement lasted 20 years.

Now, Americans are once again working well into their winter years, but they're facing a very different challenge. Thanks to the nation's transition from a manufacturing powerhouse to service economy, the demands facing senior workers today tend to be mental rather than physical. U.S. jobs, on the whole, require more brainpower than they used to. And while some mental abilities hold steady with age -- verbal skills and job know-how, for example -- others are subject to an inevitable decline after the age of 50. This slowdown affects nearly everyone: The typical senior takes twice as long as a youngster to complete a simple number-sequencing test. "There are dramatic differences," says Bill Beckwith, a Naples, Fla., neuropsychologist.

Bill Horne of Clearwater, Fla., started to notice his brain slowing down two years ago. The 62-year-old says that if he were retired and playing golf, he wouldn't mind. But as Clearwater's city manager, he oversees 1,600 employees and a $375 million budget. He was spending more and more time preparing for meetings, rereading reports and juggling notes. He found himself telling the mayor and city council, "Sorry, I'll have to get back to you on that." His doctor, Steve Scranton at Brain Fitness Centers of Florida, one of a growing number of physicians who specialize in "cognitive rehab," prescribed a daily regimen of mental drills, such as memorizing number sequences. Horne says the exercises, combined with a better diet (more salads, fewer carbs), produced a marked improvement: "I overcame the sluggishness."

Of course, not all cerebral slippage can be reversed in rehab. Doctors measure cognitive function on the horribly named Global Deterioration Scale, which ranges from 1 (doing just fine!) to 7 (needs to be spoon-fed). Most working folks, including seniors, could be classified as 1. Those who register in the 2 range experience frequent memory slips. By the time you hit 3, a professional job becomes hard to manage. Beckwith recalls one client, an accountant in his 80s, who was still keeping the books for a large department store. It took him all week to finish tasks that used to take a single day.

Where deficiencies are

Researchers have identified typical areas of mental decline. First, the elderly learn at a slower pace. This isn't a big problem in blue-collar jobs or fields like general medicine, management and law, in which professionals rely heavily on pattern matching, accumulated knowledge and expertise. In fact, people tend to thrive in these occupations well into their 70s and 80s. It can be a serious challenge, however, for an executive leader in a fast-paced industry. Multitasking ability also hits the skids. An older author interrupted by a phone call requires extra time to resume her writing, for example -- if she manages to remember what she was doing in the first place.

Then there's the decline in processing speed. An older person might not absorb speech as fast as his or her young co-workers are talking, and won't understand what's being said, says Lisa Schoonerman, co-founder of VibrantBrains, a California-based brain-fitness coaching program. Businesses like Schoonerman's have been gaining traction; the brain-training sector's revenue has tripled in the past five years, to $400 million. But most seniors cope on their own, inventing little work-arounds at the office to hide their deficiencies. They take copious notes when meeting with the boss and make light of enjoying another senior moment, says Rohn Kessler, a psychologist who coaches executives at his Boca Raton, Fla., outfit Sparks of Genius. "Underneath," he adds, "they're scared to death."

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Smiling but terrified

David Weiner's brain is working just fine, thank you very much. Still, he's dealing with his own little carnival of anxieties. From the outside, his life looks pretty good. His new job as a direct-mail and printing broker can pay $75,000 a year in commissions. He lives in a swanky Chicago suburb, where his youngest daughter earns straight A's at a top private school; the other is in her junior year at a prestigious East Coast art college. And he plays the part of the optimist. Frank and outgoing, with big ears and snapping brown eyes, he smiles constantly as he chatters away in his office, quoting Kerouac, Eastern proverbs and favorite historians. It's crucial, he says, between calls with clients, to stay upbeat and focused. Because the truth is, he says, "I've got one foot over the edge."

Weiner had kids late in life. The 67-year-old says that it kept him young, but he's still paying high school tuition, while his peers collect Social Security. His retirement savings took a big hit in the stock market, his house lost a third of its value, and he burned through the remaining equity while between jobs. His younger daughter, a high school senior, has set her sights on prestigious private universities across the country, including Rice, Brown and Yale, and Weiner isn't sure how he'll pay the tab.

And the pressure isn't just financial. Weiner's best friend, Joe, died suddenly a few years ago, and that left him pondering his own mortality -- and his legacy. He never was crazy about the printing business, and he'd love to start over, writing and marketing for environmental causes. In fact, his one consolation is an Eco-Tips blog he writes for his employer's website. Every week, he posts a long, advice-driven article on pet topics like water conservation. But that doesn't help pay the bills, and it hasn't attracted any new opportunities. The way things are looking, Weiner faces another 10 years in the printing biz.

Like many of his boomer peers, Weiner doesn't mind working -- in fact, studies show that older workers are the happiest, and a recent poll by the Employee Benefits Research Institute found that 92% of seniors cite "wanting to stay active and involved" among their reasons for working. But the hope was that in their golden years they'd set the terms and do the work they love. What's more, seniors coming out of retirement for financial reasons often face a massive loss in pay and prestige. Last year, folks over age 62 who took a new job saw a 36% cut in their hourly wage, on average, compared with a 2% cut for workers in their 20s and 30s. So while many seniors would like to start over at a new company or even launch a new career, they decide there's too much at stake, says Mary Hladio, the CEO of Cincinnati HR consulting firm Ember Carriers. In your 30s, you can absorb the risks of failure, she says. "In your 50s and 60s, it's over."

Weiner seems resigned to that notion. "I should work more diligently at upping my sales," he says. And so every morning, he shows up at the office in a crisp white shirt and tie, takes a seat on a partially deflated exercise ball (it's better for his back) and starts making calls. The goal: to pump his commissions back to pre-2008 levels. After all, the family needs $150,000 a year just to stay afloat.

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