Evaluating Speaker-Listener Cognitive Effort in Speech Communication Through Brain-to-Brain Synchrony: A Pilot...

Area of Science:

• Neuroscience
• Cognitive Science
• Linguistics

Background:

• Cognitive effort in speech processing is challenging to quantify.
• Brain-to-brain synchrony offers a novel metric for communication efficiency.

Purpose of the Study:

• To investigate brain-to-brain synchrony as a measure of cognitive effort in verbal communication.
• To compare interbrain synchrony between native-to-native and native-to-nonnative English speakers using functional near-infrared spectroscopy (fNIRS).

Main Methods:

• fNIRS was used to measure brain activity in speakers and listeners during storytelling.
• Sequential scanning quantified brain-to-brain synchronization in speaker-listener dyads.
• Listener comprehension and discourse fluency were behaviorally assessed.

Main Results:

• Native-to-native communication showed stronger brain-to-brain coupling than native-to-nonnative communication.
• Listeners exhibited more hesitation when retelling stories in accented English.
• Reduced interbrain synchrony correlated with increased cognitive effort and delayed comprehension.

Conclusions:

• Cognitive effort in verbal communication involves both listener and speaker.
• Brain-to-brain synchrony serves as a reliable indicator of cumulative communicative effort.
• Interbrain synchrony is a valuable tool for understanding the neural underpinnings of communication efficiency.