Early Brain Stimulation After Stroke
Non-invasive brain stimulation may help stroke survivors recover speech and language function.
Between 20 and 30 percent of stroke survivors have aphasia, which affects their ability to grasp language, read, write or speak. It’s most often caused by lesions in areas of the brain that control speech and language.
“For decades, skilled speech and language therapy has been the only therapeutic option for stroke survivors with aphasia,” said Alexander Thiel, M.D., study lead author and associate professor of neurology and neurosurgery at McGill University in Montreal. “We are entering exciting times where we might be able in the near future to combine speech and language therapy with non-invasive brain stimulation earlier in the recovery. This could result in earlier and more efficient aphasia recovery and also have an economic impact.”
In the small study in Germany, researchers treated 24 survivors with several types of aphasia. Thirteen received transcranial magnetic stimulation (TMS) and 11 got sham stimulation.
The TMS device is a handheld magnetic coil that delivers low intensity stimulation and elicits muscle contractions when applied over the motor cortex.
“We believe brain stimulation should be most effective early, within about five weeks after stroke...”
During sham stimulation the coil was placed over the top of the head where there is a large venous blood vessel and not a language-related brain region. The intensity for stimulation was lower so that participants still had the same sensation on the skin but no effective electrical currents were induced in the brain tissue.
Patients received 20 minutes of TMS or sham stimulation followed by 45 minutes of speech and language therapy for 10 days.
The TMS groups’ improvements were on average three times greater than the non-TMS group. They used German language aphasia tests, which are similar to those in the United States, to measure language performance of the patients.
“TMS had the biggest impact on improvement in anomia, the inability to name objects, which is one of the most debilitating aphasia symptoms,” Thiel said.
“We believe brain stimulation should be most effective early, within about five weeks after stroke, because genes controlling the recovery process are active during this time window,” he said.