Improved language performance in Alzheimer disease following brain stimulation

Area of Science:

• Neuroscience
• Neurology
• Cognitive Science

Background:

• Alzheimer disease (AD) is characterized by progressive cognitive decline, including language impairments.
• Repetitive transcranial magnetic stimulation (rTMS) is being investigated as a potential therapeutic intervention for cognitive deficits in AD.

Purpose of the Study:

• To evaluate the long-term cognitive effects of rTMS applied to the left dorsolateral prefrontal cortex (DLPFC) in patients with Alzheimer disease.
• To assess the persistence of cognitive improvements following rTMS treatment in AD patients.

Main Methods:

• Ten AD patients were enrolled in a multiple-baseline study, randomly assigned to either a 4-week real rTMS protocol or a 2-week placebo followed by 2 weeks of real rTMS.
• High-frequency rTMS was administered daily (5 days/week) over the left DLPFC for 25 minutes per session.
• Cognitive performance, specifically auditory sentence comprehension, was assessed at 2 and 4 weeks post-treatment initiation and at an 8-week follow-up.

Main Results:

• A significant improvement in auditory sentence comprehension was observed in the real rTMS group compared to baseline and placebo.
• Real rTMS treatment led to enhanced performance in AD patients.
• The observed cognitive improvements demonstrated a lasting effect, persisting for 8 weeks after the cessation of rTMS treatment.

Conclusions:

• The study provides preliminary evidence that rhythmic rTMS can yield persistent beneficial effects on sentence comprehension in Alzheimer disease patients.
• rTMS may offer a novel therapeutic strategy for addressing language dysfunction associated with AD, potentially when used alongside other treatments.