Aphasia is a language disorder caused by stroke and other acquired brain injuries that affects over two million people in the United States and which interferes with life participation and quality of life. Anomia (i.e., word- finding difficulty) is a primary frustration for people with aphasia. Picture-based naming treatments for anomia are widely used in aphasia rehabilitation, but current treatment approaches do not address the long-term retention of naming abilities and do not focus on using these naming abilities in daily life. The current research aims to evaluate novel anomia treatment approaches to improve long-term retention and generalization to everyday life.

This study is one of two that are part of a larger grant. This record is for sub-study 1, which will adaptively balance effort and accuracy using speeded naming deadlines.

Study 1: Evaluate the benefits of balancing effortful and errorless learning via adaptive naming deadlines.

• Study design: The investigators will enroll 30 people with aphasia in a randomized within-subjects crossover design comparing trained words in three retrieval conditions. Stimuli will be balanced across conditions using an established item-response theory algorithm developed by Dr. Hula (consultant). Participants will receive 8 sessions of treatment per condition (2x/ week for 4 weeks), with probes administered at baseline and 1 week, 3 months, and 6 months post-treatment. Condition treatment order will be randomly assigned and counter- balanced across participants. In total, Sub-study 1 includes typically 3-4 (but up to 6) assessment sessions, 24 treatment sessions, and 24 baseline and follow-up probe assessment sessions per participant over an approximately 10-month period, but up to 18 months. Data collection will take place at the Language Rehabilitation and Cognition Laboratory (LRCL) at the University of Pittsburgh, in participants' homes, or in private rooms in public spaces (e.g. libraries, community centers).
• Participants: The investigators will recruit 30 male and female community-dwelling people with aphasia >6 months post- onset of aphasia due to left-hemisphere ischemic or hemorrhagic stroke. Aphasia diagnosis will be confirmed by Comprehensive Aphasia Test (CAT) performance and medical history. Investigators will exclude potential participants with a history of other acquired or progressive neurological disease, significant language comprehension impairments, unmanaged drug/alcohol dependence, and severe diagnosed mood or behavioral disorders that require specialized mental health interventions.
• Assessment Procedures: Participants will be tested on a comprehensive initial battery of standardized assessments characterizing their aphasia severity and overall language profile, naming and discourse abilities, semantic processing, verbal short-term and working memory at baseline. Patient-reported measures of treatment motivation and pre-post changes in communication effectiveness will also be measured in response to each treatment condition. These tests will ensure that our participants well-characterized from a behavioral perspective, and measures will be used in secondary analyses and model development exploring predictors of treatment response.
• Treatment description: Each training trial will consist of a fixation cross and picture presentation. A repetition cue (audio recording and written from of the target) will be provided to participants based on the deadlines described above. Participants will be instructed to name the picture and indicate when they have given their final answer via key press, with responses also timed and scored by clinician key press. In the errorless condition, they will be instructed to repeat the target, while in the other conditions they will be asked to try to name the picture independently before they hear the target. Once they have indicated that they have provided their final answer, they will receive accuracy feedback on the computer screen based on clinician scoring. To maximize the clinical relevance of this study, investigators will control total amount of treatment time (8 hours) between conditions, instead of controlling the total number of trials. This is because many more trials can be completed per hour in the errorless or balanced conditions compared to the effort-maximized condition, and investigators want study outcomes to practically inform clinicians on how best to spend limited treatment time.

Inclusion Criteria:

• Existing diagnosis of chronic (>6 months) aphasia subsequent to left hemisphere ischemic or hemorrhagic stroke.
• Impaired performance on 2/8 sections of the Comprehensive Aphasia Test.

Exclusion Criteria:

• History of other acquired or progressive neurological disease.
• Significant language comprehension impairments
• Unmanaged drug / alcohol dependence.
• Severe diagnosed mood or behavioral disorders that require specialize mental health interventions.

The data sharing plan for this study includes the publication of discourse measures and other study data on Aphasia Bank (R01-DC008524), a large online repository of aphasia behavioral data that supports a great deal of productive aphasia corpora research. De-identified test scores, treatment, and probe data, and audio and/or video recordings of norming, probe, assessment, and treatment data will be shared to this repository for all study participants.

Investigators will also make our experimental task files, protocols, and de-identified study data available through Open Science Framework (https://osf.io/) to encourage the replication, collaboration, and expansion of our work by other research groups.

Last, investigators plan to publish a modeling and statistical package in open-access software, R, which will include functionality for calculating speed-accuracy tradeoff optimality using our multinomial ex-Gaussian response time model approach.

Data will be shared at the time of study publication without planned end to access.

Anyone who wishes to access the data.

Research assistants responsible for coding data will be masked to treatment condition.