Functional connectivity of human chewing: an fcMRI study

Area of Science:

• Neuroscience
• Neuroimaging
• Motor Control

Background:

• Mastication is a crucial orofacial function with complex neurobiological control mechanisms.
• Previous research primarily utilized animal models, leaving human masticatory control less understood.
• Investigating human brain activity during mastication is essential for understanding this fundamental function.

Purpose of the Study:

• To elucidate the functional brain networks engaged during mastication in humans.
• To utilize functional connectivity magnetic resonance imaging (fcMRI) to map brain activity during a gum-chewing task.
• To identify specific brain regions and their interconnections involved in the control of mastication.

Main Methods:

• Employed functional connectivity magnetic resonance imaging (fcMRI) in 29 healthy young adults.
• Participants performed a gum-chewing task during the fcMRI scanning session.
• Utilized seed-based fcMRI analyses focusing on the motor cortex and cerebellum as regions of interest.

Main Results:

• Demonstrated reciprocal functional connectivity between bilateral motor cortices and areas including the post-central gyrus, cerebellum, cingulate cortex, and precuneus.
• Identified functional connections originating from cerebellar seeds to contralateral cerebellar hemispheres, bilateral sensorimotor cortices, left superior temporal gyrus, and left cingulate cortex.
• Provided the first identification of specific functional central networks active during human mastication.

Conclusions:

• The study successfully mapped the functional brain networks supporting mastication in humans.
• Findings highlight the intricate interplay between the motor cortex, cerebellum, and associated cortical and subcortical regions during chewing.
• This research lays the groundwork for future investigations into the neurobiology of masticatory control and related orofacial functions.