Anodal Tdcs Over Left Inferior Frontal Gyrus To Augment Word-Finding Therapy In Sub-Acute Post-Stroke Aphasia: Multicentre Double-Blind Randomized Controlled Trial Protocol

Abstract

Background: Aphasia affects roughly a third of stroke survivors initially, with persistent word-finding difficulties in a substantial subset. tDCS can modulate cortical excitability and promote neuroplasticity, potentially enhancing speech and language therapy (SLT). This protocol describes a multicentre, double-blind RCT comparing anodal tDCS over left inferior frontal gyrus (IFG) plus intensive word-finding therapy versus sham in sub-acute aphasia. Primary outcome is picture-naming; secondary outcomes assess generalization to connected speech, everyday communication, participation, quality of life, and cost-effectiveness.

Methods: Fifty-eight right-handed Dutch near-native speakers aged 18–80, less than three months post-onset aphasia, will be randomized to active anodal tDCS (1 mA, 20 min) or sham during two separate intervention weeks of 45-minute word-finding therapy, two weeks apart, within standard rehabilitation. The anode is placed at F5 (left IFG) and cathode at Fp2 (contralateral supraorbital). The Boston Naming Test (BNT) is assessed before and after each week and at 6 months; secondary measures include Aphasia Severity Rating Scale (ASRS), Amsterdam-Nijmegen Everyday Language Test (ANELT), EQ-5D, Stroke and Aphasia Quality of Life (SAQOL), Community Integration Questionnaire (CIQ), and a cost-analysis questionnaire. Randomization uses device-coded blocks per center; participants, therapists, and coordinators are blinded.

Discussion: This design provides within-subject recovery trajectories across two intervention weeks and longer-term follow-up, addressing prior limitations of small samples and inconsistent protocols. Findings will inform tDCS implementation for sub-acute aphasia, including effectiveness and cost-effectiveness.