Non-invasive brain stimulation as add-on therapy for subacute post-stroke aphasia: a randomized trial (NORTHSTAR)

Area of Science:

• Neuroscience
• Neurology
• Speech-Language Pathology

Background:

• Post-stroke aphasia recovery can be enhanced by non-invasive brain stimulation (NIBS) combined with speech therapy.
• This study investigated the efficacy of 1 Hz subthreshold repetitive transcranial magnetic stimulation (rTMS) and 2 mA cathodal transcranial direct current stimulation (ctDCS) on the right pars triangularis.

Purpose of the Study:

• To evaluate the effectiveness of rTMS and ctDCS as adjunctive therapies for subacute post-stroke aphasia.
• To determine if NIBS influences naming, semantic fluency, and comprehension recovery.

Main Methods:

• A three-armed, sham-controlled, blinded, prospective study involving 63 patients with left middle cerebral artery infarcts.
• Patients received 10 days of rTMS, ctDCS, or sham stimulation alongside speech therapy (ST).
• Primary outcomes included Z-score changes in naming, fluency, and comprehension; secondary outcome was the Unified Aphasia Score (UnAS) change.

Main Results:

• Repetitive transcranial magnetic stimulation (rTMS) significantly improved naming at 30 days post-treatment compared to ctDCS and sham stimulation (p=0.01).
• This naming improvement with rTMS was primarily observed in patients with an intact Broca's area.
• No significant differences were found for other primary outcomes; trends suggested potential benefits of NIBS in patients with intact Broca's areas for UnAS.

Conclusions:

• Low-frequency rTMS targeting the right pars triangularis demonstrated a delayed positive effect on naming recovery in subacute post-stroke aphasia.
• The findings suggest that NIBS may be most beneficial for naming recovery in patients whose Broca's area remains morphologically intact post-stroke.