Submental Surface Electromyography Research Articles

An Analysis of Lingual Contribution to Submental Surface Electromyographic Measures and Pharyngeal Pressure During Effortful Swallow

Huckabee M-L, Steele CM. An analysis of lingual contribution to submental surface electromyographic measures and pharyngeal pressure during effortful swallow. Objective To evaluate the influence of tongue-to-palate pressures on submental muscle contraction and oral and pharyngeal pressure dynamics during effortful swallowing maneuver. Design Comparative analysis of 2 task strategies on biomechanic measures of swallowing. Setting Research laboratory in a free-standing research facility. Participants Consecutive volunteer sample of 20 healthy participants (age range, 20−35y). Interventions Not applicable. Main Outcome Measures Peak amplitude of submental surface electromyography and orolingual and pharyngeal manometric pressure at 4 locations. Results General linear model analysis of variance revealed statistically significant greater amplitudes for the tongue emphasis condition of effortful swallow at all measured sensors ( P<.004). Conclusions Tongue-to-palate emphasis during execution of effortful swallowing increases amplitudes of submental surface electromyography, orolingual pressure, and upper pharyngeal pressure to a greater degree than a strategy of inhibiting tongue-to-palate emphasis.

Breathing and Swallowing Pattern Abnormalities in Multiple Sclerosis

Background: Recent data suggest a high prevalence of dysphagia and recurrent aspiration in moderately and severely disabled multiple sclerosis patients. Methods: The study participants included 60 healthy subjects, median age 47 years and 20 moderately to severe disabled patients with multiple sclerosis, presenting with a median EDSS of 5.75 (median age 48 years). A 2-channel computer-assisted system was used to obtain concurrent respiratory and submental surface electromyography signals. Subjects were seated in an upright position and asked to swallow boluses of 5, 10 and 25ml water and 5ml applesauce presented in random order. Eight swallows of each bolus volume and viscosity were recorded. For each swallow, (1) the latency between the onset of swallowing and swallowing apnea (SA); (2) the duration of each SA; (3) the duration of the submental activity, and (4) the pattern of breathing before and after each SA was evaluated. Results: In healthy subjects and patients a total of 2.560 swallows was performed. The latencies between the onset of swallowing and SA were significantly reduced in MS patients. In the patient group the durations of SA and submental activity were significantly prolonged (ANOVA, p<0.001) at all bolus volumes and correlated significantly (r=0.76, p<0.0001). Expiration/inspiration before SA occurred in healthy subjects in 87.3%/12.7% and in patients in 89.4%/10.6% (n.s.). Expiration/inspiration after SA occurred in healthy subjects in 98.9%/1.1% and in patients in 93.0%/7.0% (p<0.0001). The difference was highly significant at all bolus volumes and viscosities. Conclusion: Our study confirms that the great majority of swallowing apneas in healthy subjects are followed by expiration. However, in multiple sclerosis patients the SA is followed by inspiration more frequently than expected which might increase the risk of aspiration or laryngeal penetration. Furthermore, the durations of SA and submental swallowing activity are significantly increased. The prolonged SA duration most probable reflects a protective mechanism owing to the prolonged swallowing activity in multiple sclerosis patients. Our findings indicate a disturbed temporal coordination between respiration and swallowing in multiple sclerosis patients.

Motor strategy in rapid sequential swallowing: new insights.

This study examined the physiological properties and movement strategies of normal, rapid sequential swallowing during simultaneous videofluoroscopy (VFS) and submental surface electromyography (EMG). Ten subjects performed discrete (5 and 15 cc) and sequential (150 cc in tilted and upright head postures) swallowing tasks. Analyses included VFS event timing, movement/bolus passage characteristics, EMG amplitude waveforms, and peak and offset EMG amplitudes. Results revealed that sequential swallows were significantly shorter than discrete swallows in several VFS event durations, but significantly longer in pharyngeal transit and stage transition times. The hyolaryngeal system exhibited a cyclical "rise and partial fall" movement pattern during sequential swallows on VFS, corresponding to a repetitive "activation and partial deactivation" characteristic on EMG. Greater peak EMG amplitude for sequential than discrete swallows was found in 6/10 subjects. Pharyngeal bolus merging, preparatory laryngeal gestures, and penetration without aspiration were also observed in some subjects on VFS. Intersubject differences were significant in timing measures and EMG amplitude. Our findings of individual variability and subject-specific strategies for task accommodation support the notion of built-in plasticity in the deglutitive motor complex.

Temporal and durational patterns associating respiration and swallowing.

This study obtained initial normative data on the temporal coordination of respiration and swallowing events in 12 young adults using a first-generation Respirodeglutometer. In addition, direction of airflow before and after deglutive apnea was obtained. Three swallows of two viscosities of bolus material were performed by each subject, yielding a total of 72 swallows. Qualitative and quanitative analyses were performed. Time of onset of submental surface electromyography and time of laryngeal movement were found to differ between males and females. Males began submental muscle contraction before females and laryngeal movement after females. Duration of deglutition apnea for all swallows was 0.75 +/- 0.14 sec. Expiration occurred before the deglutition apnea 93% of the time and after the deglutition apnea 100% of the time. A modal pattern of events obtained with the Respirodeglutometer was present in 42% of the swallows, and an additional 47% had only one event differ from that order.

Laryngeal movement, oropharyngeal pressure, and submental muscle contraction during swallowing

This study examined temporal relationships of laryngeal movement, oropharyngeal pressure and submental muscle contraction during swallowing. Techniques used to obtain the temporal measures were electroglottography (EGG), oropharyngeal manometry, and submental surface electromyography. Liquid bolus swallows were performed by 40 normal subjects evenly divided by young and elderly, men and women. Results of this investigation suggest that the EGG waveform is reflective of the temporal aspects of laryngeal movement during swallowing and that the EGG has potential as a behavioral modification technique in swallowing therapy. A case study is presented to illustrate the use of the electroglottograph for biofeedback.

Coordination of deglutition and phases of respiration: effect of aging, tachypnea, bolus volume, and chronic obstructive pulmonary disease.

The effects of aging, tachypnea, bolus volume, and chronic obstructive pulmonary disease on the coordination of swallowing with the phases of respiration were studied by concurrent respirography and submental surface electromyography. Study findings showed that in young healthy volunteers, during rest, there is preferential coupling of subconscious swallowing with the expiratory phase of continuous respiration. This preferential coupling of swallowing with expiration was found to increase relative to other phases of respiration during water swallows and tachypnea (P < 0.05). Respiratory phase occurrence of swallowing and postdeglutitive resumption of respiration during exacerbation of chronic obstructive pulmonary disease was found to be significantly different compared with the basal state (P < 0.05). Respiratory phase occurrence of subconscious swallowing in the elderly was found to be different from the young (P < 0.05). Position had no significant effect on the coordination of swallowing and phases of respiration. We concluded that in resting young volunteers the majority of deglutitions are coupled with the expiratory phase of swallowing. This coupling is increased in frequency by the presence of a liquid bolus and tachypnea. And finally, age and chronic obstructive pulmonary disease alter this coordination significantly.

Coordination of deglutitive glottic closure with oropharyngeal swallowing

The goals of this study were to quantify the temporal relationship between swallow-induced glottic closure and (a) signals of swallow initiation, such as hyoid bone movement, tongue base movement, and mylohyoid electrical activity; (b) pharyngeal peristalsis; (c) laryngeal elevation; (d) vestibular closure; and (e) oropharyngeal barium bolus transit. Eight normal subjects (age 20–30 yr) were studied by concurrent transnasal video laryngoscopy, pharyngeal intraluminal manometry, and submental surface electromyography. The manometric, electromyographic, and both video recordings were synchronized with one another using a specially designed event marker. Dry, 5-ml water, and 5-ml barium swallows were recorded. Frame-by-frame analysis of the video endoscopic recordings showed that deglutitive laryngeal kinetics consisted of vocal cord adduction associated with transverse approximation of the arytenoids followed by vertical approximation of arytenoids to the base of the epiglottis followed by laryngeal ascent and epiglottic descent. Onset of swallow-induced vocal cord adduction preceded the onset of hyoid bone movement, base of the tongue movement, and submental surface myoelectric activity by 0.33 ± 0.04 (SE) s, 0.31 ± 0.04 s, and 0.38 ± 0.04 s, respectively. Onset of vocal cord adduction also preceded the initiation of peristalsis in the nasopharynx and its propagation to oropharynx and upper esophageal sphincter by 0.64 ± 0.05 s, 0.82 ± 0.05 s, and 1.08 ± 0.04 s, respectively. The time between the onset of vocal cord adduction and their return to full opening was 2.2 ± 0.09 s. It was concluded that (a) among events evaluated, vocal cord adduction is the initial event during the swallowing sequence; (b) laryngeal kinetics during deglutition have distinctive features, and their close coordination with other swallowing events suggests that they are an essential feature of the swallowing program; and (c) abnormal laryngeal kinetics or lack of coordination between the glottic closure mechanism and oropharyngeal bolus transport may have an important role in swallow-induced aspiration.