NCT04166513

Effects of Transcranial Direct Current Stimulation (tDCS) on Language

Effects of tDCS in Language Recovery and Reorganization in Chronic Aphasia

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 25 (actual)
• Sponsor: Medical College of Wisconsin · Academic / Other
• Sex: All
• Age: 18 Years – 85 Years
• Healthy volunteers: Not accepted

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.

Conditions

• Stroke
• Aphasia

Interventions

Type	Name	Description
DEVICE	Targeted Transcranial Direct Current Stimulation	High-Definition-tDCS will be delivered via a battery-driven constant direct current stimulator (Soterix) using a 4x1 montage (1 central anodal electrode and 4 cathodal electrodes) arranged in a HD-cap. The current is turned on and increased in a ramplike fashion over approximately 30 seconds until reaching a strength of no more than 2mA, with a current density equal to 0.08mA/cm2. Stimulation will be maintained no longer than 20 minutes, and stimulation will be applied to the targeted region.
DEVICE	Active Control Transcranial Direct Current Stimulation	High-Definition-tDCS will be delivered via a battery-driven constant direct current stimulator (Soterix) using a 4x1 montage (1 central anodal electrode and 4 cathodal electrodes) arranged in a HD-cap. The current is turned on and increased in a ramplike fashion over approximately 30 seconds until reaching a strength of no more than 2mA, with a current density equal to 0.08mA/cm2. Stimulation will be maintained no longer than 20 minutes, and stimulation will be applied to the active control region.
BEHAVIORAL	Phonologic-Focused Speech Therapy	Participants are asked to generate or choose from a list phonologic information about a target picture.
BEHAVIORAL	Semantic-Focused Speech Therapy	Participants who have difficulty retrieving an object name are given hierarchical clues or asked questions about the objects function as a way of activating the semantic network for that object, leading to eventual retrieval of the target word.

Timeline

• Start date: 2019-12-13
• Primary completion: 2024-07-01
• Completion: 2024-07-01
• First posted: 2019-11-18
• Last updated: 2025-10-03
• Results posted: 2025-03-21

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated device study