Transcranial Magnetic Stimulation + Language Therapy to Treat Mild Aphasia

Aphasia is an acquired disorder of language that occurs in approximately 30% of individuals with stroke and impacts approximately 1 million Americans (see NINDS.NIH.gov). Current treatments for aphasia are only modestly beneficial, so there is a clear need for more efficacious therapy.

Previous research has demonstrated that TMS improves language performance in persons with aphasia and the benefit has been shown to be sustained. All studies of which we are aware, however, have included participants with moderate/severe aphasia. The issue of mild aphasia has received little attention to date but as there is an increasing recognition that even very mild language deficits have important negative consequences for employment and social well-being. This study will aim to treat mild aphasia with TMS and SLT emphasizing conversations speech.

One limitation of TMS has been variability in response; TMS has shown good within-subject reliability but more substantial variability between subjects. In recognition of these issues, "electrical field" (e-field) models have been developed to account for these individual differences in anatomy. We will the utilize e-field models in conjunction with an individually determined resting motor threshold to generate a personalized treatment regimen that is likely to ensure that all subjects receive the same TMS intensity relative to their individual motor threshold and greatly reduces the possibility of under- or over-dosing with respect to TMS intensity. We will employ continuous theta-burst stimulation, 600 brief electrical pulses delivered in 40 seconds, over the right front part of the brain (pars triangularis).

Participants who are enrolled can expect to undergo a battery of tests to define their language function as well as a research MRI scan that will be used to guide TMS therapy and to assess the size and location of the stroke and its impact on brain pathways. After baseline testing, subjects will undergo treatment using TMS (or sham) + SLT for 10 sessions (Monday-Friday) over the course of 2 consecutives week. Follow-up assessment of language functioning will be assessed immediately, 2 months and 4 months after treatment.

Participants will be compensated for their time and travel.

Inclusion criteria

• Left Hemisphere stroke
• Stroke occurred more than 6 months ago
• Mild Aphasia (WAB AQ score > 85)
• Proficient in English

Exclusion criteria

• Ongoing substance or alcohol abuse
• Other neurological disorders, beside stroke (i.e. dementia, traumatic brain injury, multiple sclerosis)
• Active psychiatric disorders (i.e. bipolar disorder, schizophrenia)
• Pacemaker or cardiac defibrillator
• Diagnosis of tinnitus
• Epilepsy, or seizure in the past 6 months