Aphasia is a speech impairment that can result from injury to the language areas of the brain. The language areas of the brain are primarily found in the left hemisphere, however, due to the extensive neural networks and complexity of the brain, the right hemisphere can also be engaged to support language.
Past research has shown mixed results of the ability of the right hemisphere to be "recruited" to support language ability in people with aphasia. A recent review of the past literature determined that right hemispheric recruitment may indeed help recover language skills, but only if language rehabilitation therapy is applied during specific conditions, such as applying therapy within a critical time frame after the injury. The extent and location of the brain injury is also critical for a successful recruitment of the right hemisphere to support language ability.
The researchers suggest that rehabilitation used to recruit the right hemisphere to support language impairments can be a useful intervention for aphasia, but only as a complementary therapy for certain patients, within a short period of time after the injury.
Anglade C, Thiel A, & Ansaldo AI. The complementary roles of the cerebral hemispheres in recovery from aphasia after stroke: A critical review of the literature. Brain Injury. (February 2014).