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La parakinésie brachiale oscitante
Yawning: its cycle, its role
Warum gähnen wir ?
 
Fetal yawning assessed by 3D and 4D sonography
Le bâillement foetal
Le bâillement, du réflexe à la pathologie
Le bâillement : de l'éthologie à la médecine clinique
Le bâillement : phylogenèse, éthologie, nosogénie
 Le bâillement : un comportement universel
La parakinésie brachiale oscitante
Yawning: its cycle, its role
Warum gähnen wir ?
 
Fetal yawning assessed by 3D and 4D sonography
Le bâillement foetal
http://www.baillement.com

mystery of yawning 

 

 

 

 

mise à jour du
29 octobre 2017
Mult Scler Relat Disord.
2017;17:179-183.
Spontaneous yawning in patients with multiple sclerosis:
A polygraphic study
Erkoyun HU, Beckmann Y, Bülbül NG, Incesu TK,
Kanat NG, Ertekin C.
 
Department of Neurology, Cigli Region and Training Hospital, Izmir, Turkey

Chat-logomini

 
T. Postert D, Pëhlau S, Meves Nastos H, Przuntek. Pathological Yawning as a symptom of SEP J of neurology 1999;243(3):300-301
 
Abstract
Patients with multiple sclerosis (MS) suffer from the repetitive yawning and sleep problems. Yawning is observed in MS and other central nervous system disorders and yawning and swallowing may be controlled by the network of the brain stem. Therefore, it is important to investigate the MS patients with various clinical and radiological locations in order to understand the role of brainstem on the yawning mechanisms. One hour polygraphic recording would be crucial method for this purpose, because it is easy to observe spontaneous yawning (SY) and spontaneous swallowing (SS) together with their electrophysiologic counterparts. Previous studies reported that contagious yawn and swallow are temporally related and frequency of swallows was increased within 10s of post yawn period in normal adult subjects.
 
The authors have re-investigated this phenomenon by studying the SY and SS in polygraphic recording in normal subjects and patients with MS. Then they hypothesized that SY is expected to be increased in MS patients.
 
49 patients with MS and 19 control subjects were recruited in this study. The authors used a twelve-channel electroencephalography (EEG) device. Five channels were for electromyography (EMG) recording. They also used one channel for laryngeal sensor for vertical movements of the larynx during swallowing. Cardiac rhythm, respiration and sympathetic skin responses were synchronously recorded during swallowing. They evaluated rate of total SY, swallows inside the yawning, before and after 10s of the yawning and yawning unrelated with swallowing.
 
Patients with MS yawned more frequently than healthy controls (p = 0,044). It was obvious that the yawning unrelated with spontaneous swallow was also significantly increased compared to normal controls (p = 0,047), whereas swallowing inside the yawn or before and after 10s of yawning were not significantly different in both groups. Among 49 MS patients, 16 (32.6%) had brainstem involvement. Yawning was observed in only 6 (37.5%) of them.
 
Yawning is significantly increased in MS patients compared to normal controls by using the polygraphic method. There is no direct relation of the brainstem and the origin of yawning in MS patients according to clinical picture and MRI findings. However safe swallows during yawning could suggest that there is still need to some brain stem mechanism and/or oropharyngeal reflexes. Difficulties must be emphasized to detect anatomic localization in MS because of relapsing pattern of disease.
Résumé
Les patients atteints de sclérose en plaques (SEP) souffrent de bâillements répétitifs et de somnolence. Le bâillement est observé au cours de la SEP et d'autres maladies du système nerveux central sans doute parce que le bâillement et la déglutition sont contrôlés par les réseaux neuronaux du tronc cérébral.
 
Il est donc intéressant d'étudier les patients atteints de SEP en prenant en compte cliniquement et radiologiquement les différentes localisations lésionnelles afin de comprendre plus précisément le rôle du tronc cérébral dans les mécanismes du bâillement.
 
Un enregistrement polygraphique d'une heure serait une méthode intéressante dans ce but, car il est facile d'observer des bâillement spontanés (SY) et la déglutition spontanée (SS) et leurs équivalents électrophysiologiques. Des études antérieures ont rapporté que le bâillement contagieux et la déglutition sont liés temporellement. La fréquence des déglutitions est augmentée dans les 10s qui suivent un bâillement chez les sujets adultes normaux.
 
Les auteurs ont réexaminé ce phénomène en étudiant le SY et le SS en enregistrement polygraphique chez des sujets normaux et chez des patients atteints de SEP. Ensuite, ils ont émis l'hypothèse que SY devrait être augmenté chez les patients atteints de SEP.
 
49 patients atteints de SEP et 19 sujets témoins ont été recrutés pour cette étude. Les auteurs ont utilisé un dispositif d'électroencéphalographie (EEG) à douze canaux. Cinq canaux étaient destinés à l'enregistrement électromyographique (EMG). Ils ont également utilisé un canal pour un capteur laryngé enregistrant les mouvements verticaux du larynx pendant la déglutition. Le rythme cardiaque, la respiration et les réponses cutanées sympathiques ont été enregistrées de façon synchrone pendant la déglutition. Ils ont évalué le nombre de bâillements spontanés et les déglutitions en lien avec un bâillement, avant et après 10s du bâillement et les bâillements sans lien avec la déglutition.
 
 
Les patients atteints de SEP bâillent plus fréquemment que les témoins en bonne santé (p = 0,044). Il est apparu que les bâillements sans lien avec la déglutition spontanée sont significativement plus fréquents par rapport aux contrôles normaux (p = 0,047), alors que la déglutition en lien avec le bâillement n'est pas significativement différente dans les deux groupes. Parmi 49 patients atteints de SEP, 16 (32,6%) avaient une atteinte du tronc cérébral. Le bâillement a été observé chez seulement 6 (37,5%) d'entre eux.
 
Le bâillement est significativement augmenté chez les patients atteints de SEP par rapport aux témoins normaux en utilisant la méthode polygraphique. Il n'y a pas de relation directe entre le tronc cérébral et le déclenchement du bâillement chez les patients atteints de sclérose en plaques d'après la clinique et les résultats de l'IRM.
 
 
Cependant, les déglutitions après le bâillement suggèrent qu'il existe encore une activité fonctionnelle du tronc cérébral et / ou des réflexes oropharyngés. Il faut néanmoins souligner les difficultés qui existent à la localiser anatomiquement les lésions de SEP, en raison de l'évolution par poussées de la maladie.
 
1. Introduction
 
Spontaneous yawning (SY) is an involuntary and stereotyped behavior common to human being (Barbizet, 1958; Ertekin et al., 2015; Walusinski and Deputte, 2004). It is more likely to take place during wake-sleep and sleep-wake transitions (Provine et al., 1987). It can be easily recorded together with the spontaneous swallowing (SS) in the polygraphic study in lying position in one hour of the rest (Ertekin, 2014; Ertekin et al., 2013) or in all night sleep (Uludag, Tiftikcioglu and Ertekin, 2016).
 
Patients with multiple sclerosis (MS) suffer from the repetitive yawning and sleep problems (Gallup et al., 2010; Sandyk, 1998; Thompson, 2014). Yawning is common in young female patients who are fully ambulatory with a relapsing-remitting course of disease (Sandyk, 1998). Yawning is observed in MS and other central nervous system disorders such as hypothalamus and cerebral cortical disorders and yawning and swallowing may be controlled by the network of the brainstem (Cattaneo et al., 2006; Postert et al., 1996; Thompson et al., 2016; Walusinski, 2009; Zilli, Giganti and Uga, 2008). There are some evidence that the brainstem is the origin of the spontaneous yawning behavior:
 
1. Excessive yawning behavior is associated with the ischemic lesion in the brainstem (Cattaneo et al., 2006; Singer et al., 2007)
 
2. Distorted yawning movements and complete volitional paralysis of the bulbar muscles are seen in Locked- in Syndrome (Bauer, Gerstenbrand and Hengl, 1980; Krasnianski et al., 2003).
 
3. Yawning movements persist in anencephalic infants (Daquin, Micallef and Blin, 2001).
 
4. Excessive yawning behavior is also observed in patient with motor neuron disease (Williams, 2000).
 
Postert et al. (1996) described excessive yawning as a symptom of the brainstem localization of MS. On the contrary diverse opinions were also reported (Gallup, 2014; Krestel et al., 2015; Platek, 2010; Thompson, 2014).
 
Yawning may be related with the Central Pattern Generator (CPG) of the brainstem where the swallowing and respiration are controlled (Jean, 2001). If we look at yawning from the view of swallowing and respiration; there is a progressive slow opening of the mouth while the dilatation of pharynx, larynx, thorax and lowering of diaphragm muscle could be shown by the radiological methods (Barbizet, 1958). The increase of saliva flow was reported during yawning (Inomata et al., 2005). Furthermore SS occurs frequently in the period of SY (duration about 4&endash;10 s) in normal subjects, patients with brainstem infarction and Parkinson's disease (Ertekin et al., 2015). Therefore it is important to investigate MS patients with various clinical and radiological locations in order to understand the role of brainstem on yawning mechanisms. Yawning was evaluated by electrophysiological methods previously (Thompson et al., 2014a, 2014b; Thompson, 2013; Thompson and Bishop, 2012). However in these studies, association of SY and SS were not assessed and no muscle except masseter was recorded. One hour polygraphic recording would be crucial method for this purpose, because it is easy to observe SY and SS together with their electrophysiologic counterparts (Ertekin, 2014; Ertekin et al., 2013, 2015; Uludag et al., 2016).
 
It is well known that yawning is classified into two types as spontaneous and contagious. Both are similar in their motor action and their triggering mechanism, although their evolutionary nature and social meaning are different (Baenninger, 1997; Provine and Hamernik, 1986). It was reported that contagious yawn and swallow are temporally related and frequency of swallows was increased within 10 s of post yawn period in normal adult subjects (Abe et al., 2015). They concluded that swallows after contagious yawning were increased. We have re-investigated this phenomenon by studying the SY and SS in polygraphic recording in normal subjects and patients with MS. We investigated the SY and its association with SS within 10 s before and after yawning. We expected if this phenomenon is present, it may indicate a physiological linkage between brainstem swallowing and yawning, if not, there is no intimate relationship between the brainstem and yawning.
 
Then we hypothesized that SY is expected to increase in MS patients. However the origin of yawning cannot strictly located to the brainstem uniquely, when clinical and radiological findings of the patients are compared. Difficulties must be emphasized to detect anatomic localization in MS because of relapsing pattern of disease. SS can be recorded inside of the yawning and increased rate of SS just before and after SY would demonstrate the relationship in between brainstem and yawning.
 
4. Discussion
 
Yawning was significantly increased in MS patients. When we analyzed subgroups of yawning, there is no increase rate of the SS just before and after the SY within 10 s. Secondly, there was no direct relations for the brainstem and the origin of yawning in MS patients according to clinical picture and MRI findings.
 
The mean sleeping time for normal controls and the patients with MS was not statistically different from each other during the approximately 60-min recordings. This was important because number of SS during sleep was known to be reduced in comparing to awake state (Afkari, 2007; Ertekin et al., 2013; Sato and Nakashima, 2006; Uludag et al., 2016).
 
Yawning was significantly increased in MS patients compared to normal controls. This was well known finding and previously reported (Baker, 2002; Gallup et al., 2010; Postert et al., 1996; Sandyk, 1998; Thompson, 2014). It is interesting that patients with MS suffer from thermoregulatory dysfunction, repetitive yawning and sleep problems (Gallup et al., 2010).
 
Yawning is proposed that could be controlled by the network of brainstem (Cattaneo et al., 2006; Postert et al., 1996; Walusinski, 2009; Zilli et al., 2008). However, 14 of MS patients' who were yawned MRI and clinical findings could not demonstrate the involvement of the brainstem. Only 6 of them had brainstem involvement. Our findings on MS patients without brainstem involvement were compatible to other previous studies which did not suggest yawning was under the control of the brainstem (Gallup, 2014; Krestel et al., 2015; Platek, 2010; Thompson, 2014).
 
There are few theories that were developed for yawning and its origin, among these, the most recent and popular one is the cortical theory of Thompson (2014). Indeed the yawning, known to be associated with elevated cortisol levels; may also occur in association with fatigue; and this may explain why people with MS yawn when they are observed to be frequently fatigued (Thompson and Richer, 2015; Thompson, 2017, 2014). Similarly plasma ACTH levels at night and just prior to awaking from sleep is also associated in humans with yawning and stretching behavior. Recurrent episodes of uncontrollable yawning and body stretching also occur in a subset of patients with MS during electromagnetic cranial stimulation. This kind of treatment was also found favorable to therapeutic response to magnetic stimulation (Sandyk, 1998). Our patients had never search any treatment for their yawning and stretching clinical responses. Although we could not observe any clinical improvement but this should also be investigated in further studies.
 
Another physiological fact is the SS which was recorded inside of the SY, but this was not found statistically significant. However, it was reported that contagious yawn and swallow are temporally related and frequency of swallow was increased within 10 s of post yawn period in normal adult subjects (Abe et al., 2015). In SY, we could not found such a relationship that the yawning after 10 s is able to increase rate of swallows. Thus our finding may not be compatible with finding of Abe (2014).
 
SY and SS can often be seen together but not always associated with one another. Since the duration of yawning is about 4&endash;10 s (Askenasy, 1989; Ertekin et al., 2015; Walusinski, 2009), SS could overlap with a yawning randomly and there is a mechanism for the safe swallow during yawning. Because SY associated with swallows seen to be safe for our patients and normal controls. We did not observe any clinical signs of aspiration such as coughing just after yawning, neither could we observed any graphical changes suggesting the laryngeal penetration. However this observation could not be contrary for the final relationship between yawning and brainstem where the origin of yawning could be different but the safe swallowing during yawning could be explained by some brainstem mechanism or/and related oropharyngeal reflexes. This point of view should be elucidated in further studies.
 
In Conclusion:
 
1. Yawning is significantly increased in MS patients compared to normal controls by using the polygraphic method.
 
2. The SY and the SS are sometimes associated and overlapped in both normal controls and MS patients without any aspiration into the airway.
 
3. There is no increased rate of SS just below and after the SY within 10 s
 
4. There is no direct relation of the brainstem and the origin of yawning in MS patients according to clinical picture and MRI findings. However safe swallows during yawning could suggest that there is still need to some brainstem mechanism and/or oropharyngeal reflexes.
 
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