By BENEDICT CAREY

The same digital screens that have helped nurture a generation of insomniacs can also help restore regular sleep, researchers reported on Wednesday. In a new study, more than half of chronic insomniacs who used an automated online therapy program reported improvement within weeks and were sleeping normally a year later.

The new report, published in the journal JAMA Psychiatry, is the most comprehensive to date suggesting that many garden-variety insomniacs could benefit from the gold standard treatment — cognitive behavior therapy — without ever having to talk to a therapist. At least one in 10 adults has diagnosable insomnia, which is defined as broken, irregular, inadequate slumber at least three nights a week for three months running or longer.

In the study, led by researchers at the University of Virginia, doctors recruited 303 people ages 21 to 65 over the internet. Half were randomly assigned to receive education and advice on insomnia — a digital “placebo,” of sorts, though an active one, in that such advice often helps people sleep better. The other half got a six-week focused online therapy product, called SHUTi.

SHUTi is not the only digital insomnia therapy product on the market. Sleepio, which costs $300 for a year’s access, and is offered by a London-based company, also incorporates cognitive therapy. And it was also found in a randomized study to have good results.

The research team tracked the participants, assessing their sleep quality every several months, using standardized questionnaires. After a year, 57 percent of the people using the online therapy program were sleeping normally, compared with 27 percent of those who had gotten only advice and education.

Dr John Torous, co-director of the digital psychiatry program at Beth Israel Deaconess Medical Center and Harvard Medical School said the one caveat for all of them is adherence. “When you stop paying people to be in a study, when they stop getting reminder phone calls, they often stop doing it,” he said. “It’s like a gym membership that way; people may do it twice and then let it go.”

Nonetheless, the potential of online therapies to reach huge numbers of people makes it likely that they will become first-line therapy in many cases.