Targeting Executive Function and Language Impairments with tACS Combined with Behavioral Intervention in Primary...

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neurology

Background:

• Executive function (EF) deficits are common in neurodegenerative diseases like Primary Progressive Aphasia (PPA).
• PPA primarily presents with language impairments, but EF is also affected.
• The relationship between EF and language processing in PPA requires further investigation.

Purpose of the Study:

• To test if targeting domain-general executive functions can improve domain-specific language functions in PPA.
• To evaluate a combined behavioral and neurostimulation treatment protocol for PPA.

Main Methods:

• A case series of four Greek-speaking individuals with PPA received 15 daily sessions of Computerized Cognitive Training (CCT) for EF and alpha-rhythm transcranial alternating current stimulation (tACS) over the left dorsolateral prefrontal cortex (DLPFC).
• Assessments of EF and language performance were conducted pre- and post-treatment.
• Performance was compared to healthy controls.

Main Results:

• Significant improvements were observed primarily in executive functions post-treatment.
• Language functions showed heterogeneous improvements across the four participants.
• Most patients showed numerical gains on the N-back task, but overall patterns varied.

Conclusions:

• The combined EF-focused intervention yielded improvements in both executive functions and language processing in PPA patients.
• These findings support the hypothesis that enhancing domain-general functions can positively impact domain-specific abilities.
• Preliminary results warrant larger clinical trials to generalize findings for the PPA population.