Dennis Butler puffed excitedly into a small black box. Each breath caused a small silver ball to carom off white plastic dials, while numbers flashed quickly on the digital display. The whirring of the spinners played counterpoint with the gentle plunk of the flippers, until the ball finally slipped out of play.

His turn over, Butler moved back, allowing John Uber to launch a new ball by tapping a special pad.

Yes, it is pinball, but the machine is no ordinary arcade game. It is a specially designed system for quadriplegics and paraplegics that boasts exceedingly fast remote-control technology.

"ArcadeAccess," as the machine is called, can be played by able-bodied people, by wheelchair users with full upper-body function and by people who can move only an eyelash.

"It's true equality in a fast-paced, physical environment," Uber said during a demonstration at the National Institutes of Health. "For wheelchair users like me, that's rare -- and wonderful."

The two young men were competing against Dan Goodman, the inventor of the machine and the president of Silverthorn Group, a technology firm that specializes in electronic devices for people with disabilities. And the game was a spirited competition.

Butler, 22, who lost the use of his arms and legs after a skiing accident, used the "sip-and-puff" mouth technique to play. A hard sip of air starts the game, a hard puff shoots the ball, and soft sips and puffs control the left and right flippers, respectively.

Uber, a 24-year-old graduate of the University of Maryland and a communications engineer for an electronics firm, was a senior in high school when an automobile accident left him paralyzed from the waist down. He controlled the action by tapping touch-sensitive pads mounted next to the usual control buttons.

"I used to love pinball when I was young," said Butler, who is studying for a master's degree at George Washington University. "After school, I would go down to some of the arcade places in Georgetown and play endlessly. Now, I must rely on other people to help me with the daily challenges faced by all quadriplegics. But while I am playing on this machine, I am the 'real' me: I can turn it on by myself, I can play it by myself, I can compete with non-disabled people."

His father, Charles Butler, a supervisor of therapeutic recreation in the pediatric research program at NIH, said pinball is an important therapeutic tool.

"For people with many options, pinball may seem like a harmless diversion. But to a disabled person in a wheelchair, the game can provide something special in terms of overall rehabilitation," he said. "When people become seriously injured, a lot of them feel that their life is over. They have limited control over their environment, which adds to the stress and helplessness they feel. Pinball gives some physical control, and so it serves a critical emotional and mental need. This is very important in improving their self-esteem."

Norman Bass, chief medical officer at Harmarville Rehabilitation Hospital in Pittsburgh, said he hopes to use such pinball machines to help patients "relearn visual-motor, auditory-communication and organizational skills required for independent living."

The machine is intended for elderly people, accident victims, those with war-related injuries, those with birth defects and those with degenerative diseases.

Dennis Butler was the inspiration for the machine. He was a sophomore at Williams College when he was paralyzed from the neck down.

The idea stemmed from a conversation between Butler's father and Goodman, who at the time was supplying and servicing several pinball machines in the adolescent wing at NIH. Charles Butler suggested that since Goodman was studying to be an electrical engineer, perhaps he could design a modified pinball machine for people with handicaps like his son's.

That was three years ago, and Goodman took the advice to heart. Uber helped with the engineering.

Their first challenge was to make the machine wheelchair-accessible. That was a far harder task than just sawing six inches off the legs, because simply lowering the machine wouldn't solve the problem. The front part of the playing field had to be thinned from 18 to five inches, so that someone in a wheelchair could sit underneath it and play at table level. That also meant moving nearly all of the electronics of a regular machine to the back. Once that was done, the machine worked fine for someone like Uber, who has complete control over his upper body, but was of little use to Dennis Butler, who can't push pinball buttons.

Next came the hard part. Goodman developed the remote transmitter with jacks for various communication devices. In addition to the "sip-and-puff" breath controller, the transmitter can be hooked to a joystick, an eyelash flicker mechanism, bite switches, muscle or voice vibration sensors, or a special pad that looks like a drummer's practicing box. A tap on one of the five rubberized pads by a toe, a palm, a chin or any other part of the body causes the remote transmitter to tell the machine what to do.

Once the machine and the transmitter were working properly, the trick was to get them working fast. The machine now has a delay of only about a fiftieth of a second between the transmitter and the flippers.

Goodman said that if remote-control technology can work for something as complicated and time-critical as a pinball machine, there is a possibility it can be adapted for other purposes. Apparently he is not alone in his thinking. ArcadeAccess was one of four products to win Washington Technology's best new product award for 1990, competing against a range of defense, computer and other inventions.

"To the best of my knowledge, this is the first time that a disability-related device has won a general technology award. It suggests the growing importance of technology to improve the quality of life" for people with disabilities, Goodman said.

"Pinball is not the be-all and end-all, but it's an important step in the right direction," Goodman added. "Electronic devices for people with disabilities typically lag 15 years behind similar products for general consumers. I hope that ArcadeAccess is one of a growing number of products designed for people of all abilities, and that manufacturers will begin to design equipment so that everyone can use them."

Dennis Butler is hopeful. "Combining this system with advanced robotics, I see very little that can't be done," he said. "Perhaps in 10 years, I will be able to feed myself, cook dinner for a friend and possibly even drive a car using a remote-control transmitter."