Training-induced cortical plasticity compared between three tongue-training paradigms

Area of Science:

• Neuroscience
• Motor Control
• Cortical Plasticity

Background:

• Investigating training-induced cortical plasticity is crucial for understanding motor learning.
• Tongue-based training paradigms offer novel approaches for motor rehabilitation and cognitive enhancement.
• Gender differences in motor cortex responses to training require further exploration.

Purpose of the Study:

• To compare the effects of three distinct tongue-training paradigms on cortical plasticity.
• To examine gender-specific differences in training-related neuroplasticity.
• To assess subjective experiences (motivation, fun, pain, fatigue) associated with different tongue training methods.

Main Methods:

• Forty-eight participants were randomized into three groups: therapeutic tongue exercises (TTE), Tongue Drive System (TDS), or tongue protrusion task (TPT).
• Transcranial magnetic stimulation (TMS) was used to measure motor evoked potentials (MEPs) and motor cortex mapping before, immediately after, and 1 hour after training.
• Subjective ratings of motivation, fun, pain, and fatigue were collected post-training.

Main Results:

• TDS and TPT significantly lowered resting motor thresholds and increased tongue MEP amplitudes, indicating enhanced cortical plasticity, unlike TTE.
• Men exhibited higher MEPs than women in the TDS group across all time points.
• No significant changes were observed in the first dorsal interosseous (FDI) control muscle or tongue cortical motor map areas.
• TDS was rated highest for motivation and fun, while TTE was perceived as most painful.

Conclusions:

• Tongue-based training paradigms differentially modulate cortical plasticity, with TDS and TPT being more effective than TTE.
• Gender influences motor cortex excitability in response to tongue training.
• Subjective feedback highlights the importance of engagement and comfort in tongue-training interventions.