EBE FARIDA RAOUF lives alone in Manhattan and, like many elderly people, fears a sudden injury or illness. When she recognized the symptoms of a heart attack four years ago, she called for help, lay down on pillows on her floor and left the front door ajar for paramedics.

Today Mrs. Raouf, 74, a former nursing assistant, is taking part in a test of a new home monitoring system that uses motion detectors to record her daily habits and, once a pattern is established, reports any unusual activities. Initially skeptical of the devices, Mrs. Raouf says the only change she has noticed is the occasional modem noise on her phone line when the system dials in to update her reports, she said.

"I feel a bit more secure," she said of the test. "A lot of seniors live alone and die alone, but this gives me a little peace of mind."

Mrs. Raouf is part of a demographic segment highly sought after by General Electric, Intel, Honeywell and other companies that want to deliver security and better quality of life for senior citizens without using high-cost nursing services or other paid companions. These companies view online tools as a way to move beyond the "call for help" pendants or bracelets that were popularized two decades ago but go unused in an estimated 75 percent of emergencies - and to head off problems before they become emergencies.

The heart of the motion-sensor system Mrs. Raouf is helping to test is software from Living Independently (www.livingindependently .com), a start-up company in New York. Data from the sensors is used to create a baseline for activity: waking time, ordinary visits to the bathroom, time spent in the kitchen or on the couch. A small white base station contains a modem that dials in every two hours when the phone line is available and posts the data to a private, secure Web site maintained by Living Independently.

The reports are color-coded: normal conditions are in green and changes, which may be cause for concern, are reported in yellow or red. The system can also be set to notify an attendant by phone if there is a change in conditions.

George Boyajian, executive vice president of Living Independently, said the automated system did more than help older people maintain their independence. "There are people who are resentful of having a baby sitter," he said. "It's old technology but smart programming that allows early detection and warning, instead of notification after an accident."

Several of Mrs. Raouf's children live within a few miles, but her system reports to Doris Colon, a director of social services at Goddard-Riverside Community Center, which manages services for elderly people in Phelps House, the apartment building where Mrs. Raouf lives on the Upper West Side. Ms. Colon said she was evaluating the system to see if it reassured elderly people who live alone or family members who may live far away.

She said the monitors had resulted in only one warning signal, when another Phelps House resident had fallen asleep on the toilet, and that no life-threatening situations had arisen during the test.

Living Independently is not the only company seeking to put technology to work helping care for elderly people. From robots that "speak" reminders on how to make tea or when to eat lunch, various systems are being tested in research laboratories.

Carnegie Mellon University, the University of Michigan and the University of Pittsburgh are developing NurseBot, a robotic face that displays emotion by asking questions or smiling at certain verbal cues, and responds verbally to questions.

Helping older people manage medication regimens is an important focus for researchers. The University of Rochester has an animated character, Chester the Talking Pill, that can be displayed on computer monitors to alert a viewer to the possibility of adverse drug interactions. E-Pill, a company in Wellesley, Mass., has commercialized another technology, selling a $750 "intelligent" dispenser that dishes out up to 60 daily doses of pills and then reminds the patient for up to 90 minutes that the pills are ready.

If the medication is not taken, the machine reports the event to a password-protected E-Pill Web site and dials a list of four phone numbers to alert someone.

"Patients don't like technology that screams out 'I'm different,' and caregivers often start looking only once a crisis arises," said Stefan Solvell, president of E-Pill. And because insurers will not pay for the E-Pill dispensers, Mr. Solvell said, they are not sold by drugstores or medical supply companies.

It is also clear that technology plays only a partial role in helping older people stay healthy and maintain their independence. The elderly thrive on interaction, which can be social or technological, said Dr. Joseph Coughlin, director of the Massachusetts Institute of Technology AgeLab, which studies aging-population issues. He said that remote monitoring was little more than a home alarm system, when what was really needed was a network of people to keep older people active and engaged - either in person, by phone or by e-mail.

"People live well and live long for other people," Dr. Coughlin said. Pets, even virtual ones like the Tamagotchi, might be more effective than machines in persuading elderly people to exercise, take medicine or eat regularly.

Beyond the issue of knowing which seats are occupied or cabinet doors are opened, voice reminders piped in through radio, television or PC speakers can help with daily chores, said Eric Dishman, head of an Intel research team on technology for care of the elderly. Mr. Dishman leads a group that is exploring ways to help people with Alzheimer's disease or diminished cognitive skills remain at home. Broadband and wireless Internet connections, networking and other systems could lend help instantly and remotely in a familiar voice, he said.

"Baby boomers have changed health care, child care and, next, they'll change elder care," Mr. Dishman said. "People will see this technology today in caring for their parents, and we'll see what baby boomers will be like as they age."

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