Inclusion Criteria:  18 years old Native English Speakers Capacity to provide informed consent Right-handed Corrected to normal vision Left hemisphere cerebral stroke at least 6 months prior to testing Presence of severe-to-moderate, non-fluent aphasia, i.e. Aphasia Quotients of 0-50 on the Western Aphasia Battery-Revised (PsychCorp, 2007) Corrected pure tone threshold (octave frequencies 250- 4000 Hz) norms for their age and gender41,42 NOTE: Audiometry data will be collected for all participants by lab personnel trained by an audiologist in a sound-attenuated booth. Based on our ongoing aphasia studies, we expect that ~30% of participants will use hearing aids; we will not exclude these individuals but rather include hearing aid use as a covariate in analyses.  Exclusion Criteria:  Severe concurrent uncontrolled medical problems (e.g. cardiorespiratory impairment).