Human Auditory-Motor Networks Show Frequency-Specific Phase-Based Coupling in Resting-State MEG.

Area of Science:

• Neuroscience
• Auditory Perception
• Motor Control

Background:

• Auditory-motor coupling is vital for music and speech, involving brain oscillations, especially in the beta band.
• Previous research linked auditory-motor phase synchrony to temporal prediction, but its intrinsic nature and specificity were unclear.

Purpose of the Study:

• To investigate if auditory-motor phase coupling is an intrinsic brain feature or task-dependent.
• To determine if phase synchrony is unique to the auditory-motor system compared to other sensorimotor modalities.
• To assess the influence of musical training on auditory-motor coupling.

Main Methods:

• Resting-state magnetoencephalography (MEG) was used to measure phase locking values (PLVs) and phase transfer entropy (PTE).
• 90 healthy participants (musicians and non-musicians) were studied.
• Phase synchrony was analyzed between motor regions and auditory or visual cortical areas across different frequency bands.

Main Results:

• Significantly higher PLVs were observed in auditory-motor connections compared to visuomotor connections across all frequency bands.
• The right primary auditory cortex and right ventral premotor cortex showed the highest phase synchrony.
• Auditory-motor and visuomotor coupling were stronger in the right hemisphere, with notable differences in theta, alpha, and beta bands between auditory and visual inputs.

Conclusions:

• Motor phase synchrony is intrinsically enhanced in auditory cortical regions compared to visual ones, particularly in the theta-beta frequency spectrum.
• Alternating information flow loops exist between auditory-motor structures, varying with frequency.
• This intrinsic coupling supports low-latency integration of sounds and movements through synchronized neural activity.