This randomized controlled comparative effectiveness study examines manipulation of a key component of an established and efficacious treatment for naming impairments in aphasia, along with cognitive and brain correlates of treatment success. Study participants will be randomly assigned to one of two treatment conditions comparing two different versions of Semantic Feature Analysis treatment. Their performance on standardized and study-specific measures will be used to determine which version of the treatment provides superior outcomes, and measures of automatic language processing and functional brain imaging will also be used to identify the underlying neurocognitive mechanisms associated with positive treatment response.

This randomized comparative effectiveness trial examines whether active manipulation of a key component of semantic feature analysis (SFA) treatment for word-finding difficulty in aphasia improves outcomes. 40 study participants will be recruited and randomized to receive one of the two versions of the treatment. The total treatment time will be equated in the two conditions.

Study participants will be housed locally at the Pittsburgh site at no cost and will be eligible to receive reimbursement for travel expenses. During the five-week treatment phase of the study, participants will receive 60 hours of SFA treatment with pre- and post-treatment assessment of their ability to name pictures of treated and untreated, semantically related nouns. Other secondary outcomes, including measures of connected speech and patient-reported communication ability will also be collected. In order to address unresolved questions about the underlying cognitive and neural mechanisms of SFA, participants will also receive concurrent pre- and post-treatment assessment of automatic word processing ability using eye-tracking methods and functional magnetic resonance imaging (fMRI). Participants will also be asked to return to Pittsburgh for two days approximately 2-3 months later for follow-up language, eye-tracking, and fMRI testing.

The language testing results will be used to determine which version of SFA treatment optimizes outcomes. The eye-tracking results will be used to infer whether SFA's positive effects can be attributed to improved activation of lexical-semantic representations, improved ability to inhibit competing representations, or both. The fMRI results will be used to identify the brain networks and activation changes associated with changes in naming ability resulting from SFA. This study will provide theoretically and clinically relevant information about how aphasia treatment should be delivered and the neurocognitive mechanisms underlying its effects.

Inclusion Criteria:

• 6 months post-onset of aphasia due to unilateral left-hemisphere (LH) stroke
• Independent in activities of daily living (ADLs) necessary to live in community-based housing or available caregiver to assist with ADLs
• Medically stable and able to tolerate intensive treatment schedule (e.g. no uncontrolled seizures, difficulty breathing, frequent migraines)
• English as a first language
• No participation in any other speech-language treatment during this study, including follow-up period
• Sufficient auditory comprehension abilities demonstrated during screening
• Sufficient naming impairment exhibited during screening

Exclusion Criteria:

• Right Hemisphere stroke
• Neurological disease other than stroke
• Significant psychiatric disorder
• Severe motor speech disorder
• Active substance dependence

Administration and scoring of all primary and secondary outcome measures will be carried out by a speech pathologist on study staff who (1) is not the treating clinician for the participant being assessed, and (2) is blind to the group assignment of the participant being assessed. Because SFA is a behavioral intervention, it will not be possible to blind the treating clinician to group assignment. It will also be impossible to definitively blind participants to their group assignment. However, we will not formally disclose to participants the group to which they have been assigned, and in the informed consent process, we will describe the conditions only in relative terms.