Prefrontal cortex rTMS enhances action naming in progressive non-fluent aphasia

Area of Science:

• Neuroscience
• Neurology
• Speech and Language Pathology

Background:

• Progressive non-fluent aphasia (PNFA) is a neurodegenerative disorder causing non-fluent speech, naming difficulties, and grammatical errors.
• Repetitive transcranial magnetic stimulation (rTMS) has shown promise in improving naming abilities in healthy individuals and Alzheimer's disease patients.

Purpose of the Study:

• To determine if modulating dorsolateral prefrontal cortex (DLPFC) circuits with rTMS can enhance naming performance in PNFA patients.
• To investigate the effects of rTMS on both object and action naming in PNFA.

Main Methods:

• Ten patients diagnosed with PNFA underwent high-frequency rTMS applied to the left and right DLPFC, as well as a sham (placebo) condition.
• Naming tasks (object and action) were performed during each stimulation condition.
• A control group of patients with semantic dementia was included.

Main Results:

• rTMS applied to both the left and right DLPFC significantly improved action naming compared to sham stimulation.
• No significant improvement in object naming was observed with DLPFC rTMS.
• rTMS showed no effect on naming performance in the semantic dementia patient group.

Conclusions:

• rTMS over the DLPFC effectively enhanced action naming in individuals with PNFA.
• The findings suggest rTMS may facilitate lexical retrieval processes, offering potential for PNFA rehabilitation.
• Further research is warranted to explore rTMS as a rehabilitative protocol for PNFA.