Effects of Transcranial Direct Current Stimulation (tDCS) on Language

Not Applicable

Completed

Conditions: Aphasia
Stroke

Interventions: Device: Active Control Transcranial Direct Current Stimulation
Device: Targeted Transcranial Direct Current Stimulation
Behavioral: Semantic-Focused Speech Therapy
Behavioral: Phonologic-Focused Speech Therapy

Registration Number: NCT04166513

Lead Sponsor: Medical College of Wisconsin

Brief Summary: This study will investigate the effects of mild electrical stimulation in conjunction with speech therapy for people with post-stroke aphasia to enhance language recovery.

Detailed Description: Aphasia is a disturbance of language, primarily caused by brain injury to the left cerebral hemisphere. Aphasia treatments include speech and language therapy and pharmacologic therapy, but several studies have found that these treatments are not completely effective for patients with aphasia, leaving them with residual deficits that significantly add to the cost of stroke-related care. Additionally, the amount and frequency of speech and language therapy delivered may have a critical effect on recovery. Therefore, there is a need for new treatments or adjuncts to existing treatments, such as brain stimulation interventions, that have the potential to show greater improvements in patients with aphasia. One such new approach for non-invasive brain stimulation is transcranial direct current stimulation (tDCS).

This study will examine the effects of tDCS during speech therapy to further examine which method or methods is best for patient recovery. Patients enrolled in the study will undergo language testing that covers a broad range of language functions. Functional Magnetic Resonance Imaging (fMRI) will be completed before and after speech therapy intervention arms to investigate the neural processes affected by tDCS and speech therapy.

Study design:

Patients will be randomly assigned to one of 2 speech therapy groups in a double-blind, partial crossover design. Patients will receive one of two different speech therapy treatment interventions to focus on specific processing deficits. Participants will undergo neuropsychological evaluation and fMRI assessment before receiving targeted or active-control anodal-tDCS for 10 therapy sessions. Participants will then be re-tested using the behavioral assessment measure and fMRI before crossing over to either receive the tDCS intervention they did not already receive, within the same speech therapy arm. They will complete a behavioral assessment and fMRI at 3 months post Treatment 2 and a final behavioral assessment at 6 months post Treatment 2.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 25

Inclusion Criteria

Patients with a language deficit from focal neurologic damage (e.g. stroke, tumor).
Patients must be adults and have English-language fluency.
Patients must be eligible to undergo MRI.

Exclusion Criteria

Advanced neurodegenerative disease (i.e. Stage 3 Alzheimer's disease) or neurologic disorder (e.g. idiopathic epilepsy, Parkinson's disease, ALS)
Severe psychopathology (e.g. schizophrenia, bipolar disorder, acute major depressive episode)
No suspected or diagnosed uncorrectable hearing or vision difficulties, or developmental disabilities (i.e. intellectual disability or learning disability).
Contraindications to MRI such as claustrophobia, implanted electronic devices, MRI-incompatible metal in the body, extreme obesity, pregnancy, inability to lie flat, and inability to see or hear stimulus materials

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Targeted tDCS with Semantic-Focused Speech Therapy	Semantic-Focused Speech Therapy	Participants will receive semantic-focused speech therapy with targeted anodal-tDCS for 10 therapy sessions.
Active Control tDCS with Semantic-Focused Speech Therapy	Semantic-Focused Speech Therapy	Participants will receive semantic-focused speech therapy with active control tDCS for 10 therapy sessions.
Active Control tDCS with Phonologic-Focused Speech Therapy	Active Control Transcranial Direct Current Stimulation	Participants will receive phonologic-focused speech therapy with active control tDCS for 10 therapy sessions.
Targeted tDCS with Phonologic-Focused Speech Therapy	Targeted Transcranial Direct Current Stimulation	Participants will receive phonologic-focused speech therapy with targeted anodal-tDCS for 10 therapy sessions before.
Targeted tDCS with Phonologic-Focused Speech Therapy	Phonologic-Focused Speech Therapy	Participants will receive phonologic-focused speech therapy with targeted anodal-tDCS for 10 therapy sessions before.
Active Control tDCS with Semantic-Focused Speech Therapy	Active Control Transcranial Direct Current Stimulation	Participants will receive semantic-focused speech therapy with active control tDCS for 10 therapy sessions.
Active Control tDCS with Phonologic-Focused Speech Therapy	Phonologic-Focused Speech Therapy	Participants will receive phonologic-focused speech therapy with active control tDCS for 10 therapy sessions.
Targeted tDCS with Semantic-Focused Speech Therapy	Targeted Transcranial Direct Current Stimulation	Participants will receive semantic-focused speech therapy with targeted anodal-tDCS for 10 therapy sessions.

Primary Outcome Measures

Name	Time	Method
Percent Correct on Picture Naming and Reading Tasks (Baseline on Items Was 0)	Upon the completion of therapy cycle (a cycle consists of 10 intervention days) and 10 weeks post	Improvement on trained, untrained and untested items used during therapy. Items will consist of words and pictures that participants will name. Percent correct on lists after each therapy cycle will be the primary behavioral outcome measure (items chosen were at baseline is 0% correct). There were 20 pictures and 20 words in each of the trained, untrained, and untested lists. Pictures were colored photographs. Cycle A is the speech therapy intervention given first, Cycle B is the speech therapy intervention given second Cycle A Trained and Untrained lists were assessed on the last day of therapy for Cycle A Cycle A Post Trained, Untrained and Untested lists were given during Behavioral Assessment 2, approximately 10-weeks post ending Cycle A. Cycle B Trained and Untrained lists were assessed on the last day of therapy for Cycle B Cycle B Post Trained, Untrained and Untested lists were given during Behavioral Assessment 3, approximately 10-weeks post ending Cycle A.

Secondary Outcome Measures

Name	Time	Method
fMRI	3 time points: pre-assessment, 10 weeks post-therapy cycle A and 10 weeks post-therapy cycle B	Rs-fMRI functional connectivity changes between time points at the site of stimulation will be assessed. Rs-FMRI functional connectivity changes between time points with the semantic network and between semantic network and perilesional phonological areas. Cortical activation patterns and ROI lateralization will be measured using an adaptive language mapping task-fMRI procedure. Activation patterns will be assessed for each task contrast within a set of ROIs thought to reflect the semantic and phonological network in healthy controls. Laterality indexes will be created using the same ROIs and their right-sided homologues to assess whether lateralization changes as a result of therapy.