TOKYO — They hang out on the side streets of the overcrowded Shibuya district, bathed in the blazing neon of a thousand bars, game arcades and fast-food stores.

They send coded messages to each other on pagers and worship the heroes and heroines of their favorite video games.

They love to drink beer and sake, sing in shoe-box-sized karaoke rooms and have their palms read by old ladies in the dim light of paper lanterns.

Call them Japan’s Generation X, its Junior Boomers.

Born at a pivotal point in history when rapid growth created a previously unknown level of prosperity here, these young people, ages 19 to 22, are developing a culture centered on technology, fantasy and a yearning to break out of the stiff confines of Japanese tradition.

Already, as they begin to enter the work force this year, no one seems to doubt that their new values and experiences will resonate and collide with Japan’s traditional corporate culture and may have a profound influence on Japanese business and society.

The core of the Junior Boomers’ generation, the offspring of the globally notorious baby boomers, were born between 1971 and 1974. They constitute a demographic force numbering 8 million here. As an attractive market and potential labor pool, they have been dissected, surveyed and psychoanalyzed by corporations and consultants.

Experts find the Junior Boomers to be pampered by their parents and unchallenged by their schools. They are physically imposing, all too often possessing limited social skills and lacking traditional loyalties. They are prodigious but skeptical consumers. And most important for this strait-laced strivers’ society, they often appear to be nonconformist, selfish and indifferent workers.

At first glance, the Junior Boomers–beneficiaries of some of the best diets and health care in Japan’s history–look very different. The men average 5-feet-8, four inches taller than their fathers. Many wear their shoulder-length hair in a ponytail. The women, too, have grown taller and favor miniskirts to show off the long, slender legs that are the envy of an older generation. The “surfer” look, now in for both sexes, requires them to use bronzing lotions or to go to “solar salons” and to bleach their hair.

Their differences, though, are more than cosmetic. Dentsu, the giant advertising agency, calls them the “Dolphin Generation” because they are said to travel in small groups. One writer calls them “slime,” contending that they have a weak sense of self and adapt to whatever environment they happen to be in. Some analysts say they conform and lack initiative. Nonetheless, others suggest they are creative individualists.

Whatever the case, early indications are that many of them won’t take readily to the suffocating conformity and frequent drudgery demanded by Japanese corporations. In surveys, young people express pity for their parents, the grinding corporate “salarymen.” The young people resolve to put their own needs first.

“I just want lots of my own time,” said Keigo Kugimoto, 20, voicing a common view. Kugimoto, who is saving his money so he can travel, works long hours delivering lunches for his father’s business. “I want to go anywhere I haven’t been,” he said. “To see lots of things. To learn what I don’t know by meeting lots of people.”

Takashi Kurokawa, 19, who wears popular baggy, knee-length shorts and desert boots, wants to work for a trading company when he gets out of school. But he knows his priorities, saying, “I want to work so I can have time to surf.”

A decade ago, a “New Breed” of young people also thought they would be different from their workaholic parents.

But raised by authoritarian fathers when Japan was still on its upward sprint, the “New Breed” turned out to be old-fashioned. While their elders initially criticized them for their ignorance about such corporate basics as knowing how to bow and greet people, they were, within a few years, suddenly winning praise. They had fallen into line, changed their ways to get ahead and were dubbed “New Hard Workers.”

The Junior Boomers are different, analysts insist. They are not made of the stuff it takes to create “corporate warriors.” They lack the “hungry spirit” on which traditional Japanese companies thrive. Traditional values like perseverance and patience have given way to instant gratification.

This Japanese generation’s defining characteristic–a life in the lap of prosperity–may explain why it differs from its counterparts around the globe, or even from its parents.

By 1970, the year when some of the first Junior Boomers were born, key elements of Japan’s infrastructure, including the bullet train and a new road system, were completed as part of two decades of rapid growth. The nation celebrated its arrival in the modern world with Expo ’70, a lavish demonstration of its cultural and technological strengths. When Junior Boomers had turned 8, half of their families had cars, 90% had color televisions.

“Just about everything you see in Japan today was already here in 1970,” said Kenichi Kobayashi, associate marketing director at Dentsu.

The early 1970s also proved to be a boom time for weddings, as the ’60s generation of student radicals began to marry and have babies. The new parents rejected their own parents’ authoritarian ways, giving their children clothes, toys, fat allowances and often private rooms. Their children were expected to study, but otherwise they seldom were disciplined.

Today, Junior Boomers enjoy average monthly allowances of $380, Dentsu experts say; they earn as much again from part-time work. The average Junior Boomer spends a hefty $70 on a single date.

Experts and young people agree that Junior Boomers will work hard–if they like their work. If bored, they are liable to show it.

Take Hideyuki Takeuchi, 18, who works at a health center and spends his days at game centers. He loves to draw. His mother paid $6,700 to enroll him in a design school. He dropped out after one month. “It wasn’t what I wanted to do,” says Takeuchi, who wears a ponytail. “Drawing was fun as a hobby, but when it became work it wasn’t fun anymore.”

Analysts describe the Junior Boomers as Japan’s first real “me” generation, possessing little sense of loyalty to country, company or even to their parents–who express some exasperation but no real clue about how or whether to try to influence the young people’s lives and conduct.

And while companies aren’t eager to hire the Junior Boomers, they are clamoring to try to find out how to sell to them. This generation represents the last major boom likely to be seen for some time in Japan, where births have been falling almost steadily for two decades. “This is the most important age group for us,” Shinsaku Sugiyama, a Shiseido Cosmetics spokesman, says. “We have to raise their loyalty to our brand now.”

But these young consumers, who saw the mindless brand worship of the late 1980s, have turned cynical about advertising, analysts note.

To better reach them, Shiseido picks out student representatives at major schools to test new products and to give out samples. Matsushita, the industrial giant that offers a range of consumer goods here, holds lotteries to choose student “monitors” who receive free products and are expected to spread the word among their friends. “The best way to sell products to this generation is through word of mouth,” Sugiyama says.

Their dress, like many of their attitudes, underscores the Junior Boomers’ fascination with things foreign. In a switch from the past, when conformist Japanese dyed their hair to ensure that it was black enough to match that of their peers, many young people bleach their hair brown to show they don’t feel the need to embrace all things Japanese. In fact, Shiseido last year used Sean Lennon, son of John Lennon and Yoko Ono, to tap into the attraction of being “half Japanese.”

While they sometimes look and act like young Americans, the members of Japan’s Generation X are different in important ways. The Junior Boomers were educated in schools where their lives were totally managed. Early on, they received hensachi , an academic score that indicated clearly where they were headed. By the time most reached junior high, they probably knew what level of university they would be able to attend–if any at all.

The young who have been through elite schools still want posts in major companies. Many adapt well. “They are even comfortable enough to ask the division head out for drinks,” said Kobayashi of Dentsu.

But for the majority of young people, who knew they would not go to elite schools, there was little incentive to work hard or to show initiative. Because they live in a compulsively orderly society, many of the young–rather than rebel–sought escape in computer games and obsessive collections of dolls or useless trivia.

Many are socially awkward and have developed their own means of communicating. At the entrance to a darkened Shibuya computer arcade, where the sound effects are deafening, Hiroyuki Matsuzawa, 21, carefully sketched his favorite video game character, a female samurai, in a notebook chained to a small table.

“It is really sad that they (the arcade management) are going to take away this book,” he said of the bound volume of graffiti in which visitors draw and write long commentaries on games and their lives.

“This is how we became friends,” he said, shrugging toward a few other pale youngsters in the arcade. Some say they traveled an hour to read and scribble in the book.

“With young people recently, we can talk on the surface, but we don’t open up inside,” Matsuzawa added.

“There are a lot of things you don’t feel comfortable saying that you can write in the book,” his friend noted.

Computer games fill a void for many Junior Boomers, who “have no sense that they are important or necessary in this world,” said Shinji Miyadai, a professor at a small Tokyo college. “While they are playing (computer) games, they feel they have a clear-cut role in the world.”

But do the Junior Boomers have the right stuff for corporate Japan?

Shigenobu Nagamori, Nippon Densan’s president, has a well-known tactic when picking recruits for his motor-manufacturing business, where he demands that workers be almost fanatic about their labor. He takes prospects out for a bowl of curry rice and watches to see which ones devour their meals fastest.

Now, among the young, he sees no famished candidates who display the proper “hungry spirit,” he complained recently in the monthly Nikkei Business.

To many young people, however, the issue is not their appetites for corporate life but how they can keep from being devoured by what they see as the overwhelming power of the Japanese company.

“In Japan, culture and company is the same,” says game aficionado Matsuzawa, who plans to work for a large publisher. “If you have your own identity, it’s OK. But if you don’t have a strong identity, you will be swept away.”