J Oral Med Pain.  2023 Dec;48(4):159-168. 10.14476/jomp.2023.48.4.159.

Coherence Analysis of Jaw and Neck Muscle Coordination during Chewing in Healthy Adults

• Song HJ
• Han SH
• Kim JY
• Im YG

• KMID: 2552113
• DOI: http://doi.org/10.14476/jomp.2023.48.4.159

Abstract

Purpose
Coordinated activity between the jaw and neck muscles is important in oral motor tasks such as chewing. This study examined coherence between the jaw and neck muscles during chewing in healthy adults.
Methods
A total of 12 healthy adults underwent electromyography (EMG) of the jaw and neck muscles during right-sided chewing at a frequency of 1 Hz. Surface electrodes were placed over the temporalis (TA), masseter (MS), anterior digastric (DA), and sternocleidomastoid (SM) muscles on the right side. EMG signals were processed for coherence and phase analysis using advanced signal processing techniques.
Results
The MS and TA muscle pair exhibited high synchronization when chewing (median coherence=0.992). Contrarily, the coherence values between the MS and DA, as well as the MS and SM muscle pairs, were relatively low (median coherence=0.848 and 0.957, respectively). Phase analysis revealed minimal temporal differences between the MS and TA muscle pair and the MS and SM muscle pair, whereas substantial phase shifts were observed between the MS and DA muscle pair.
Conclusions
During chewing in healthy adults, the TA muscle works synergistically whereas the DA muscle antagonistically with the MS muscle, and the SM muscle supports the activity of the MS muscle. The observed synchrony and coordination provide insights into the intricate interplay among these muscles during oral motor tasks.

Keyword

Coherence; Electromyography; Masticatory muscles; Muscle coordination; Neck Muscles