Inclusion Criteria- Aphasia patients with a single, unilateral, left hemisphere stroke.
- Patients must be native speakers of English
- Patients must be at least 6 months poststroke and produce mild-severe nonfluent speech. Minimum Language requirements: 2-4 word phrase length on elicited propositional speech
- Auditory Comprehension a the 25th percentile or higher on the BDAE subtests for Word Comprehension and Commands, sufficient to cooperate during testing
- The ability to name a minimum of 3 items on the Boston Naming Test at entry into study.
- Patients must understand the nature of the study and give informed consent.
- Normal right-handed controls with no history of neurological disease or substance abuse; age, education and gender-matched to the Aphasia cases.
Exclusion Criteria- Patients with more than one stroke in the left hemisphere or patients with bilateral strokes.
- Each participant must be able to have an MRI scan.
- MRI is contraindicated for pregnant women.
- Patients will be excluded if they have the following:
- Intracranial metallic bodies from prior neurosurgical procedure, implanted pacemaker, medication pump, vagal stimulator, deep brain stimulator, TENS unit or ventriculoperitoneal shunt
- Past history of seizures within one year or unexplained loss of consciousness Family history of epilepsy
- Acute, unstable medical conditions
- History of substance abuse (within last 6 months)
- Abnormal neurological exam, other than as signs of the condition being studied
- Abnormal MRI, or history of known structural brain abnormality other than as signs of the condition studied in the present protocol.
- Administration of investigational drug within 5 halflives of the drug prior to testing.