The study included 27 stroke survivors stricken with aphasia -- difficulty speaking, finding the correct words, or understanding language -- for about four years. The patients were given three hours of language training a day for 10 days.

Intense Therapy over Shorter Period

The training included constraint-induced aphasia therapy (CIAT), an intense technique that encourages patients to speak rather than using gestures or other nonverbal methods as their primary communication method. CIAT includes language games that progress from simple communication to more complex language skills.

Overall, language skills improved in 85 percent of the patients, with those improvements lasting for six months, the study said.

"Usually patients in the chronic stage of aphasia received about two hours of therapy a week over the course of a year, but we found that it is better to give the therapy within a shorter period of time," lead researcher Marcus Meinzer, of the Universitat Konstanz in Germany, said in a prepared statement.

Brain May Relocate Language Function

Meinzer said the findings were supported by the fact that the less-frequent, less-intense therapy failed to produce improvements at 6 months, even though the total amount of hours involved in therapy equaled that of short-term intensive CIAT.

The researchers said some of their previous work suggests that CIAT and intensive traditional language therapy may prompt the brain to relocate language function to an area of the brain not affected by stroke.

About 38 percent of stroke survivors have aphasia after they suffer a stroke on the left side of their brain. Many stroke survivors improve spontaneously in the six months after the attack, but as many as 60 percent continue to experience language difficulties more than six months after a stroke.

More information: The US National Institute of Neurological Disorders and Stroke has more about stroke rehabilitation.