After a hard day’s work, Rick Allen of Aptos, Calif., can’t wait to jump in his car and zone out to the music on his iPod.

“Rather than listening to the radio, I listen to my iPod because it’s my music,” he said. “There are no news or commercial interruptions, so I get to be in my own little world.”

Allen is among millions of users of Apple Computer iPods and other MP3 digital devices who depend on their tiny music players as a prime means of escape from the cares of the day.

Their numbers are growing. According to market tracker IDC, 171 million MP3 players will be shipped this year worldwide.

Easy To Get Absorbed

While people have been using portable music technology for decades - from transistor radios to Sony Walkmans - MP3 device users are more apt to become absorbed in their entertainment. That’s because they can play personally selected, high sound quality digitized music for hours, uninterrupted, with no need to flip a cassette tape or endure the ranting of some disc jockey.

Studies show that teens and young adults are spending the most time listening to their MP3 music. In a recent survey by the Harris Group, a Waterbury, Conn.-based market research firm, respondents from ages 13 to 19 said they have their MP3 devices on for four hours a day on average. Respondents in the 20-to-34 age group said their devices are on 2.7 hours a day.

With so much of the world’s population piping nonstop music into their ears for extended time periods, some critics wonder about the health and sociological impacts of these devices. They fear MP3 players are creating a population whose brains are overloaded on technology and out of touch with the rest of the world.

One neurobiology professor is singing a more positive tune. Rafael Malach of Israel’s Weizmann Institute of Science has published a study in the journal Neuron with a different take on iPods, video games and similar technologies.

His study found that when individuals are preoccupied with intense entertainment activities, part of the brain’s cerebral cortex shuts itself down for a while.

That, says Malach, is important because, rather than overloading our brains, these activities provide a release that helps the brain operate more efficiently, and better focus on tasks.

“Our results show that, when presented with a very demanding sensory task, the part of the brain involved in self-awareness shuts off,” said Malach, a visiting professor at New York University. “This is our brain’s attempt to optimize its process. At some point being conscious of yourself interferes with the learning. It can be better to let go and be absorbed by the task you’re trying to do rather than be aware of yourself and get distracted.” Malach adds that by letting the brain turn off the civilized aspects of ourselves, these technologies help create a state of escapism similar to that of Eastern meditation, a state one normally attains through discipline and study.

Marlene Goldman, a San Francisco yoga teacher, writer and radio DJ, enjoys her iPod and Eastern meditation. She doesn’t agree they have a similar effect on her brain.

Being ‘In The Moment’

“The iPod and meditation are both good tools, but they do different things for different reasons,” she said. “I meditate occasionally to quiet all the chatter, so I can get to the bigger picture. It’s kind of like brain surgery, delving into your mind to see what’s really going on.”

Like Allen, Goldman says she’s more apt to use her iPod to completely zone out.

“It’s as if my brain goes numb,” she said. “The iPod allows me to relax, but not to delve into my mind and focus the way meditation does.”

However one interprets the goals or effect of Eastern meditation, Malach sees contradictions in the findings of his study.

“Eastern and Western philosophies present two ways of looking at the world,” he said. “The Western perspective is often about somebody being in control. Eastern philosophy is more about being in the moment and letting go of the self.

“It’s ironic that this brain research involves a Western type of technology, but its results are more analogous to some Eastern philosophies, which emphasize shutting off the inner observer to truly experience reality.”