Inclusion Criteria- A single unilateral left-hemisphere stroke
- Nonfluent aphasia, with a mean length of utterance of 0-4 words and an Aphasia Quotient between 20 and 75 on the Western Aphasia Battery
- Age 21 or older.
- At least 6 months post-stroke
- Able to comply with the study protocol
- Premorbidly right-handed, as determined by the Edinburgh Handedness Inventory
- Fluent in English premorbidly
- Completed at least 8th grade education
Exclusion Criteria- More than one stroke
- Any other neurological condition that could potentially affect cognition or speech.
- Global aphasia or inability to participate in routine speech therapy.
- Major active psychiatric illness that may interfere with required study procedures.
- Untreated or inadequately treated depression.
- Has started taking a potentially confounding central nervous system (CNS) drug within the previous 2 months.
- Current abuse of alcohol or drugs
- Nursing a child or pregnant
- Participation in another drug, device or biologics trial within the preceding 90 days
- Unable to understand, cooperate or comply with study procedures
- Significant visual or auditory impairment
- History of sensitivity to ergot derivatives.
- Active medical illness or current medication that precludes safe participation in this study.