Predicting Rehabilitation Outcomes in Bilingual Aphasia Using Computational Modeling

Study Overview
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Brief Summary
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The purpose of this investigation is to implement a computational model that can predict and optimize training and cross-language generalization patterns for bilingual persons with aphasia (BPA). The proposed work will determine the best possible treatment program for each individual patient even before they are rehabilitated. In addition, the computational model allows specification of variables such as age of acquisition, language exposure/proficiency, impairment and their systematic influence on a range of language rehabilitation outcomes.

Official Title
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Double-blind Randomized Trial Investigating the Use of Computational Modeling to Predict Rehabilitation Outcomes in Bilingual Aphasia

Conditions
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Aphasia

Intervention / Treatment
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* Behavioral: Semantic Feature Analysis (SFA)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Any number of years of education Bilingual: speaking both Spanish and English (or Chinese and English) with any degree of language proficiency prior to stroke Aphasia secondary to a left-hemisphere stroke (diagnosed by a neurologist on the basis of clinical CT/MRI imaging or medical reports) Aphasia resulting from stroke or dementia Naming deficits must be present with concurrent lexical/semantic impairment Visual and auditory acuity sufficient for all assessment and treatment procedures Ability to understand study and follow study procedures for the entire length of the study Exclusion Criteria: Premorbid history of speech/language disorder Proficient in more than just Spanish and English (or Chinese and English) Overt, behaviorally noticeable, attentional limitations that interfere with completing the experimental tasks Active medical disease that may compromise participation (e.g., cancer undergoing acute treatment, unstable diabetes, renal or hepatic insufficiency, fluctuating systemic immunological disease such as systemic lupus erythematosis, etc.) Currently taking medications that are known to exert significant effects on cognitive processes, such as neuroleptics, steroids, anticholinesterase inhibitors, etc. Current drug or alcohol use or dependence that would interfere with adherence to study requirements, in the opinion of the principal investigator Inability or unwillingness of individual to give written informed consent Diagnosed with mental illness other than active depression Neurological condition other than that which resulted in aphasia

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Model-based<br>Semantic Feature Analysis training will be provided in the language that was selected by the computational model. | Behavioral: Semantic Feature Analysis (SFA)<br>* SFA training entails having the speech-language pathologist (SLP) guide the participant through generation of pertinent semantic features for pictured treatment items (e.g., category membership, physical description, location of item in context, action associated with item). Treatment is applied to a set of items in the context of single-subject, multiple baseline designs so that replication of treatment effects could be evaluated within and across participants. Treatment will be administered two times per week until prescribed accuracy levels were met during treatment probes or a maximum number of treatment sessions was completed.<br>|
| Active Comparator: Model-opposite<br>Semantic Feature Analysis training will be provided in the language opposite to that which was selected by the computational model. | Behavioral: Semantic Feature Analysis (SFA)<br>* SFA training entails having the speech-language pathologist (SLP) guide the participant through generation of pertinent semantic features for pictured treatment items (e.g., category membership, physical description, location of item in context, action associated with item). Treatment is applied to a set of items in the context of single-subject, multiple baseline designs so that replication of treatment effects could be evaluated within and across participants. Treatment will be administered two times per week until prescribed accuracy levels were met during treatment probes or a maximum number of treatment sessions was completed.<br>|
| No Intervention: Sub-Study: Computational Modeling for Bilingual Dementia and Semantic Decline<br>This is a sub-study aimed at building a computational model to simulate bilingual dementia and semantic decline. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Word Retrieval Accuracy in both languages | Accuracy of naming of pictured treated and untreated items in both languages will be assessed in probes conducted separate from treatment. Probes were conducted repeatedly throughout the study, from baseline (prior to treatment) to the end of treatment. All naming responses were scored using as correct or incorrect. A percentage accuracy was calculated for each set of items for every probe session. Baseline probe scores were compared to end of treatment probe scores to obtain individual effect sizes for each sets of items for each participant (i.e., several effect sizes were calculated for each participant). | Through study completion, an average of 10 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Psycholinguistic assessments of language processing in aphasia (PALPA) in both languages | Reading single words and understanding spoken words | Week 1 and up to 10 weeks | 
| Boston Naming Test (BNT) in both languages | Naming pictured items | Week 1 and up to 10 weeks | 
| Bilingual Aphasia Test (BAT) B and C in both languages | Assesses each of the languages of a bilingual or multilingual individual with aphasia | Week 1 and up to 10 weeks | 
| Western Aphasia Battery (WAB) in both languages | Assesses the levels of impairment of aphasia | Week 1 and up to 10 weeks | 
| Cognitive Linguistic Quick Test (CLQT) in both languages | Assesses the contribution of cognitive deficits to language dysfunction | Week 1 and up to 10 weeks | 
| Verbal fluency task (COWAT) in both languages | Assesses general fluency | Week 1 and up to 10 weeks | 
| Category fluency task in both languages | Assesses category fluency | Week 1 and up to 10 weeks | 
| Communication Effectiveness Index (CETI) for both languages | Determines communication effectiveness by proxy | Week 1 and up to 10 weeks | 
| Pyramids and Palm Trees Test (PAPT) 3 pictures version | Assesses semantic processing ability | Week 1 and up to 10 weeks | 
| Aphasia Bank | Assesses discourse | Week 1 and up to 10 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Aphasia, Bilingualism, Language therapy, Rehabilitation of speech and language disorders, Speech-language pathology