Repetitive Deep Transcranial Magnetic Stimulation Improves Verbal Fluency and Written Language in a Patient with Primary Progressive Aphasia-Logopenic Variant (LPPA)

Background:

To date, no therapies are available for the logopenic variant of primary progressive aphasia(LPPA). Even though deep repetitive transcranial magnetic stimulation (rTMS) may improve cognitive functions in some neurodegenerative disorders, no previous studies investigated its effects in patients with LPPA.

Objective:

The aim of this study was to investigate the effects on cognitive function of high frequency rTMS (hf-rTMS) delivered over the left dorso-lateral prefrontal cortex (DLPFC) through a coil designed for deep rTMS, compared to a SHAM stimulation, in a right-handed patient with LPPA.

Methods:

The patient presented a progressive language impairment (phonological errors in speech andnaming, impaired single word retrieval and sentences repetition) and predominant left perisylvianatrophy and hypoperfusion. He received four stimulation cycles (two REAL and two SHAM) each of whom lasted 20 min for 5 consecutive days. Patient’sperformances in frontal, visuo-spatial and linguistic tasks were evaluated before and after each stimulation session. Test scores after REAL were compared with those obtained at baseline and after SHAM.

Results:

Atemporary and highly significant improvement was found in the linguistic skills (both oral andwritten tasks) but not in the other cognitive domains tested, after REAL, but not SHAM stimulations.

Conclusions:

Hf-rTMS delivered over the DLPFC could improve language in LPPA by enhancing long-termpotentiation and synaptic plasticity within the stimulated and interconnected areas involved in language network. These findings might prompt future researches into the feasibility and efficacy of deep hf-rTMS as a therapeutic tool in progressive aphasia syndromes and other neurodegenerative disorders.

Related Resources: