Stuttering severity relates to frontotemporal low-beta synchronization during pre-speech preparation

Area of Science:

• Neuroscience
• Speech and Language Sciences

Background:

• The neurophysiological underpinnings of stuttering events remain largely unclear.
• Understanding how the brain prepares for speech is crucial for stuttering research.

Purpose of the Study:

• To investigate if the intention to speak influences speech production network formation in adults who stutter (AWS).
• To explore the relationship between brain activity during speech intention and stuttering severity.

Main Methods:

• Electroencephalography (EEG) was used to measure alpha and beta power modulation in 19 AWS and 19 controls during speech intention.
• Analysis focused on power modulation in specific frequency bands (alpha, low beta, high beta) across sensorimotor areas.

Main Results:

• Both groups exhibited broadband low-frequency suppression in posterior sensors upon anticipating speech.
• Frontotemporal alpha and low-beta power differed between mild and severe AWS, with increased beta power correlating with higher stuttering severity.
• These correlations were not significant prior to actual stuttered speech.

Conclusions:

• Increased beta power during speech intention in AWS may reflect stronger maintenance of the current cognitive or sensorimotor state.
• This heightened beta power could influence subsequent speech preparation and execution, potentially contributing to stuttering events.