Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Swallows”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources
PubMed2004

Fixation of the mandible changes masseter muscle activity associated with swallowing.

The purpose of this study was to investigate the effect of mandibular fixation on activity of the swallowing-related muscles during swallowing. Electromyograms in the masseter muscle, orbicularis oris superior muscle, suprahyoid muscles, and infrahyoid muscles were recorded from seven healthy humans. Electromyographic activity during swallowing was compared between an experimental condition with mandibular fixation and an experimental condition without such fixation. Duration of the swallowing phase was prolonged with mandibular fixation. Mandibular fixation significantly delayed the onset of masseter muscle activity during swallowing, although no other muscle groups showed a delay. The amount of muscle activity during swallowing was not significantly different between the two experimental conditions in any of the muscle groups. In conclusion, mandibular fixation decreases the masseter muscle activity at the initial phase of swallowing. This may be due to decreased need of the masseter muscle activity against force pulling the mandible.

Adult↗
PubMed2004

Pharynx and oesophagus evaluation during the swallow using helical computerized tomography.

PURPOSE: Videofluorography (VF) and endoscopy are commonly used for dynamic imaging (DI) of pharyngeal swallowing but do not offer transverse plane (TP) information. The aim of the present study was to evaluate helical computerized tomography (HCT) to measure the DI capability pharyngeal swallowing in the TP. METHODS: The HCT scan technique used was a single-slice cine mode with scan times of 100 ms. All 15 subjects were studied supine during dry swallow, swallowing of barium sulphate jelly and 3, 10, 15 or 20 ml of a 40% barium sulphate solution. Nine subjects repeated the test twice at more than 1 week's interval to determine the test-retest reliability. RESULTS: Swallowing leads to closure of the vocal folds, pharyngeal constriction and narrowing of the piriform sinuses allowing jelly passage between the sinuses. Laryngeal elevation then occurs with the opening of the pharyngoesophageal segment (PES). Swallowing a bolus of 20 ml produced the maximum anteroposterior and transverse diameters as well as the maximum opening area of the PES. The test-retest intraclass correlation coefficients with liquid deglutition ranged from 0.86 to 0.98. CONCLUSIONS: This study shows that HCT enables visualization of TP of PES complementing VF or endoscopic swallowing studies.

Adult↗
PubMed2004

Behavioral training for pill-swallowing difficulties in young children with autistic disorder.

INTRODUCTION: Difficulty with swallowing pills is a common problem, leading to noncompliance with treatment recommendations. Many young children with autistic disorder (AD) who also show comorbid symptoms associated with attention deficit hyperactivity disorder (ADHD) have difficulty swallowing pills. This pilot study describes our experience in teaching pill-swallowing skills to 4 children with AD who also had comorbid symptoms associated with ADHD. METHODS: Four children, aged 5-;6.5 years, were enrolled for pill-swallowing training, 3 of the children were Caucasian boys and 1 child was a Hispanic girl. All children met the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) diagnostic criteria for AD and ADHD-like symptoms. The children's verbal IQ ranged from 54-96, their nonverbal IQ ranged from 85-107, and the Preschool Language Scale-3 total language score ranged from 50-98. RESULTS: At the end of the pilot study, 2 children (50%) successfully learned to swallow the study capsules, 1 child (25%) was able to swallow the study capsules with the behavior therapist but had difficulty with the caregiver, and 1 child (25%) made slow progress and was withdrawn by the caregiver in favor of proceeding with a crushable medication for clinical care. CONCLUSION: Caregivers were appreciative of the opportunity for this short intervention. Behavioral training for pill swallowing may be indicated in some circumstances in young children with AD and/or other developmental disorders.

Attention Deficit Disorder with Hyperactivity↗
PubMed1986

Differences in the effects of hypercapnia and hypoxia on the swallowing reflex in cats.

The effects of changes in PaCO2 and PaO2 on the swallowing reflex were studied in anaesthetized, vagotomized, paralysed and artificially ventilated cats. The swallowing reflex was induced by electrical stimulation of the superior laryngeal nerve (SLN). This initially suppressed activity in the phrenic nerve (PN). The swallowing reflex was then identified by a characteristic brief burst of PN activity and a large amplitude burst of hypoglossal nerve (HN) activity. Steady-state responses to constant SLN stimulation for 60 s were measured at four carbon dioxide tensions (PaCO2 3.9, 5.1, 6.3 and 7.8 kPa) with hyperoxia (PaO2 greater than 51 kPa) and at four values of PaO2 (PaO2 56, 11.3, 6.9 and 4.8 kPa) at a fixed PaCO2 (PaCO2 4.2 kPa). Although both hypercapnia and hypoxia increased the spontaneous respiratory activity in PN and HN, the number of swallows elicited during SLN stimulation was not influenced by PaCO2, whereas a progressive decrease in the number of swallows with decreasing PaO2 was observed consistently. These results indicate that the swallowing reflex is independent of the background respiratory activity and that hypoxia depresses the swallowing reflex, whereas hypercapnia has no effect.

Animals↗
PubMed2005

Aspects of swallowing in healthy dentate elderly persons older than 80 years.

BACKGROUND: Although age-related changes resulting in slowing of the swallowing reflex and a decline in the neuromuscular control system have been reported, there have been few reports on swallowing function in dentate elderly persons. The purpose of this study was to clarify the primary influence of aging on swallowing in healthy dentate elderly persons older than 80 years who have more than 20 teeth. METHODS: Dentate elderly persons (12 male, 7 female; mean age: 81.2 years) and dentate young participants (9 male, 5 female; mean age: 26.8 years) as a control group participated voluntarily. Participants reported no clinical symptoms relating to dysphagia, neurologic impairments, or degenerative diseases, and were asked to swallow 10 ml of barium sulfate solution (10% w/v) three times. Functional swallowing was recorded on 35 mm cinefilm at 30 frames per second with a digital subtraction angiography system. Lateral images of cinefluorography of seated participants' mouth, pharynx, and larynx were obtained. Visual image analysis for qualitative and quantitative evaluation was made with a cine projector. RESULTS: No participants exhibited aspiration during three trials. Occurrence and frequencies of piecemeal deglutition, premature loss of liquid, oral and pharyngeal residues, and laryngeal penetration were significantly greater in dentate elderly persons (p <.05) than in the dentate young participants. Oral transit time, pharyngeal delay time, and pharyngeal transit time in dentate elderly persons were prolonged significantly compared with those in dentate young participants (p <.01). CONCLUSION: Physiological swallowing functions deteriorate even in healthy dentate elderly persons. This deterioration may be explained primarily by the influence of aging on swallowing.

Adult↗
PubMed1991

Videofluoroscopic analysis of the infant swallow.

A better understanding of the abnormal infant swallowing mechanism requires better knowledge of the normal infant swallow. Twenty-one full-term infants under six months of age were examined using videofluoroscopy of the swallowing portion of upper gastrointestinal examinations. Components of the oral and pharyngeal stages of swallowing were evaluated. Results showed high reliability between two raters in obtaining measurement data. There was variability in suck and oral transit time, which was correlated to the number of sucks per swallow. All infants appeared to move their tongue in a "stripping" motion, and collected the material in various sites in the oral cavity or oropharynx before initiation of the swallow. The incidence of nasopharyngeal reflux was low (9.5%). The majority of infants demonstrated a slight residue in their valleculae and hesitation in the cervical esophagus. These findings indicate that videofluoroscopy provides an objective and systematic method for analyzing the infant swallowing mechanism.

Deglutition↗
PubMed2000

The electromyographic behavior of the thyroarytenoid muscle during swallowing.

The electromyographic (EMG) behavior of the laryngeal adductors (e.g., the thyroarytenoid [TA] muscle) during swallowing has been scarcely studied. However, the detailed analysis of TA muscle is important to understand the physiology of swallowing. We investigated 14 healthy adult subjects. Activation of the TA laryngeal adductor muscle was compared with the mechanically measured laryngeal up-down movement and with the onset of excitation of laryngeal elevators, such as submental (SM) muscles, during swallowing. The laryngeal adductor of TA and laryngeal elevators of SM muscles were electromyographically (integrated/rectified) recorded. The vertical laryngeal movements during swallowing were recorded using a piezoelectric sensor. The EMG behavior of the TA muscle revealed three different activities during swallowing. The basic activity was stable; it almost started with the upward movement of larynx and after the SM-EMG onset. A fore-burst was recorded just before the upward movement of the larynx and a late-burst appeared just after the downward movement. The fore-burst was proposed to be related with oral-laryngeal reflexes, and the late-burst could be a rebound activity after a short expiration of swallowing, while the basic activity is accepted to be a part of activity of central-pattern generator of swallowing program.

Adult↗
PubMed2002

Patterns of swallowing failure following medialization in unilateral vocal fold immobility.

OBJECTIVE: To quantify the incidence of penetration and aspiration following medialization for unilateral vocal cord immobility (UVCI) and determine patterns of failure. STUDY DESIGN: Blinded analysis consecutive case series. METHODS: Prospective blinded analysis of videofluoroscopic swallowing studies of patients who had received a medialization procedure was conducted, determining the incidence of penetration and aspiration by using the Penetration-Aspiration Scale. Pharyngeal transport measures were also assessed. Associations between clinical factors and penetration-aspiration were statistically determined. RESULTS: Sixty-seven videofluoroscopic swallowing studies were reviewed in patients (mean age, 63.3 y) who had undergone vocal fold medialization (14 laryngoplasties and 53 vocal cord injections) for UVCI. Unilateral vocal cord immobility was left-sided in 56 patients (83.6%), and 50 patients (74.6%) had a postsurgical etiologic factor for their immobility. Thirty (44.8%) and 16 (23.9%) patients demonstrated penetration and aspiration, respectively. Penetration most often occurred during the swallow, but aspiration was equally likely to occur during or after the swallow. No differences in the incidence of penetration or aspiration were noted according to the side of vocal fold paralysis ( P=.20, chi test) or etiologic factor ( P=.69). Further analysis found that swallow factors significantly associated with penetration and aspiration were swallow delay ( P=.001, Wilcoxon ranked pairs test) and reduced laryngeal elevation ( P=.001), as well as bolus residues in the valleculae (P =.002), piriform sinus ( P=.001), or posterior pharynx (P =.008). CONCLUSIONS: Many patients demonstrate significant radiographic aspiration even after medialization procedures for UVCI. Although glottal incompetence is a known risk factor for aspiration, other factors including pharyngeal bolus transport are important in determining an effective swallow in UVCI.

Barium Sulfate↗
PubMed2003

Swallow function in patients before and after intra-arterial chemoradiation.

OBJECTIVES/HYPOTHESIS: To prospectively evaluate swallow function in patients with advanced head and neck cancer before and after completion of intra-arterial chemoradiation therapy and planned neck dissection. STUDY DESIGN: Prospective nonrandomized study. METHODS Swallow function was evaluated in 11 patients with resectable T4 and selected T3 head and neck cancer before and, on average, 19 weeks after completion of treatment. RESULTS: The Performance Status Scale demonstrated worse scores for both eating in public (P =.004) and normalcy of diet (P =.004) after treatment. Patients who underwent neck dissections had significantly worse scores (P =.02) in normalcy of diet. A significant decline was noted in swallowing functional measures at the time of the repeat evaluation (P =.02). Videofluoroscopic swallow studies revealed altered swallow function in 9 of 11 patients before treatment, with aspiration seen in 3 patients. Following treatment, the incidence of aspiration increased to seven patients. Tongue base retraction, reduced laryngeal elevation, and increased laryngeal vestibule penetration of thick liquid were all statistically significantly worse after treatment. The overall score on the quality of life instrument was not significantly changed from before to after treatment. CONCLUSIONS: The majority of patients demonstrated significantly worse swallow function on all three methods of analysis at 19 weeks after completion of treatment. Continued detailed monitoring of patients' swallow function is critical in determining long-term effects of intra-arterial chemoradiation therapy and neck dissection.

Adult↗
PubMed2006

Flexible endoscopic evaluation of swallowing with sensory testing.

PURPOSE OF REVIEW: Flexible endoscopic examination of swallowing with and without sensory testing is rapidly becoming a significant tool in the otolaryngologist's armamentarium for diagnosing dysphagia. Patients with swallowing disorders often present to the otolaryngologist, and an understanding of the utility of these techniques is critical. RECENT FINDINGS: Recent studies have confirmed that flexible endoscopic examination of swallowing with and without sensory testing is an exceptionally safe procedure with excellent portability. Flexible endoscopic examination of swallowing is accurate in diagnosing aspiration when compared with videofluoroscopy. Laryngopharyngeal sensory deficits as assessed by flexible endoscopic evaluation of swallowing with sensory testing are associated with cough, reflux disease, penetration, and aspiration. Both techniques have emerged as complementary to videofluoroscopic studies, rather than as replacements for the modified barium swallow. SUMMARY: Flexible endoscopic evaluation of swallowing with and without sensory testing is a safe technique that should be considered in the workup of patients with dysphagia presenting to the otolaryngologist.

Deglutition Disorders↗
PubMed2006

The effect of bolus viscosity on swallowing function in neurogenic dysphagia.

AIM: To assess the pathophysiology and treatment of neurogenic dysphagia. METHODS: 46 patients with brain damage, 46 with neurodegenerative diseases and eight healthy volunteers were studied by videofluoroscopy while swallowing 3-20 mL liquid (20.4 mPa s), nectar (274.4 mPa s) and pudding (3931.2 mPa s) boluses. RESULTS: Volunteers presented a safe and efficacious swallow, short swallow response (< or =740 ms), fast laryngeal closure (< or =160 ms) and strong bolus propulsion (> or =0.33 mJ). Brain damage patients presented: (i) 21.6% aspiration of liquids, reduced by nectar (10.5%) and pudding (5.3%) viscosity (P < 0.05) and (ii) 39.5% oropharyngeal residue. Neurodegenerative patients presented: (i) 16.2% aspiration of liquids, reduced by nectar (8.3%) and pudding (2.9%) viscosity (P < 0.05) and (ii) 44.4% oropharyngeal residue. Both group of patients presented prolonged swallow response (> or =806 ms) with a delay in laryngeal closure (> or =245 ms), and weak bolus propulsion forces (< or =0.20 mJ). Increasing viscosity did not affect timing of swallow response or bolus kinetic energy. CONCLUSIONS: Patients with neurogenic dysphagia presented high prevalence of videofluoroscopic signs of impaired safety and efficacy of swallow, and were at high risk of respiratory and nutritional complications. Impaired safety is associated with slow oropharyngeal reconfiguration and impaired efficacy with low bolus propulsion. Increasing bolus viscosity greatly improves swallowing function in neurological patients.

Adult↗
PubMed1992

Swallowing activity of lip muscles in patients with a complete upper and a partial lower denture.

In 30 partially edentulous subjects provided with an immediate complete upper and a partial lower free-end denture the lip activity in swallowing was studied before and after denture treatment and during a 2-year period of denture wearing. Electromyographic recordings of the right side upper and lower orbicularis oris, mentalis and anterior temporal muscles were obtained during swallowing saliva and during swallowing of water with and without the dentures in the mouth. In the different types of swallows recorded, the lower lip and mentalis muscles showed much stronger activity than the upper lip and anterior temporal muscles and also initiated the swallowing activity. No significant changes in mean voltages of the swallowing activity were observed during the 2-year observation period. On the other hand, the durations of the swallows showed marked increases after 1 year of denture use, when no further rebasings of the complete upper denture had been made.

Adult↗
PubMed2005

Relationships between air swallowing, intragastric air, belching and gastro-oesophageal reflux.

BACKGROUND: With each swallow a certain amount of air is transported to the stomach. The stomach protects itself against excessive distention by swallowed air through belching (gas reflux). The mechanism of belching (transient lower oesophageal sphincter relaxation) is also one of the mechanisms underlying gastro-oesophageal reflux. AIM: To investigate whether swallowing of air leads to an increase in size of the intragastric air bubble and to gastro-oesophageal reflux. METHODS: Multichannel intraluminal impedance measurement was used to quantify the incidence of swallowing of air in 20 healthy volunteers before and after a meal. Radiography was used to measure the size of the intragastric air bubble. Gastro-oesophageal reflux was assessed by concurrent impedance and pH measurement. RESULTS: The rate of air swallowing was correlated to the size of the intragastric air bubble postprandially and to the rate of gaseous gastro-oesophageal reflux. The number of air swallows and the size of the intragastric air bubble did not correlate with the number of liquid acid and non-acid reflux episodes. CONCLUSIONS: In healthy subjects, air swallowing promotes belching but does not facilitate acid reflux.

Adult↗
PubMed1998

Expert nursing knowledge in the care of patients at risk of impaired swallowing.

PURPOSE: To describe the practical knowledge of expert nurses when they assess and feed patients at risk of impaired swallowing. Observation uncovered a lack of well-developed nursing practices in assessing patients' swallowing and eating, and a wide range of interventions in the care of difficult-to-feed-patients. Finding little previous nursing research to guide practice for patients with impaired swallowing, the authors undertook a study to identify and describe the knowledge embedded in the everyday practice of nurses. DESIGN: Descriptive, exploratory using purposive sampling. Twelve nurses were identified in 1994 as expert in the care of patients at risk of impaired swallowing in one Boston, Massachusetts teaching hospital. METHODS: Data were collected using written narratives by each participant; group interviews in which nurses discussed the written narratives; nonparticipant observations and individual interviews of the expert nurses; and patients' chart review. Data were analyzed using interpretive phenomenology. FINDINGS: Most nurses in the study did not perform a complete assessment of swallowing before feeding their patients. Yet, through feeding patients, they were able to describe several components of the swallowing assessment used in their practice. CONCLUSIONS: The areas of assessment described by the nurses can serve as a template for the development of educational content and assessment tools for swallowing.

Adult↗
PubMed1994

Activity of bulbar respiratory neurons during fictive coughing and swallowing in the decerebrate cat.

1. The behaviour of medullary respiratory neurons was studied during fictive coughing and swallowing evoked by electrical stimulation of the superior laryngeal nerve (SLN) in decerebrate, paralysed and artificially ventilated cats. Fictive coughing, swallowing and respiration were monitored by recording activities of the phrenic, hypoglossal and abdominal nerves. 2. Extracellular recordings were made from respiratory neurons in the ventral respiratory group (VRG) and in the Bötzinger complex (BOT). The neuronal types analysed included decrementing inspiratory neurons (I-DEC), augmenting expiratory neurons (E-AUG) and decrementing expiratory neurons (E-DEC) from the BOT area, and augmenting inspiratory neurons (I-AUG) and augmenting expiratory neurons (E-AUG) from the VRG area. 3. During fictive coughing, all the inspiratory and expiratory neurons were active during the inspiratory and expiratory phases of coughing, respectively. The firing of both I-DEC and I-AUG neurons was increased and prolonged in association with the augmented inspiratory activity of the phrenic nerve. The activity of E-AUG neurons of the VRG did not parallel the abdominal nerve activity, suggesting the existence of additional neurons which participate in the generation of abdominal nerve activity during fictive coughing. 4. During fictive swallowing, half of I-DEC neurons fired transiently at the onset of hypoglossal bursts associated with swallowing; the firing was suppressed during the rest of the hypoglossal bursts. Other I-DEC neurons were silent during hypoglossal bursts. Some I-AUG neurons fired during the initial half of hypoglossal bursts, and others were silent. The brief phrenic activity accompanying the swallowing might have originated from this activity in I-AUG neurons. The discharges of all E-AUG neurons (BOT and VRG) and the majority of E-DEC BOT neurons were suppressed during swallowing. 5. We conclude that these five types of respiratory neurons of the BOT and VRG are involved in the generation of the spatiotemporally organized activity of coughing and swallowing, and that at least a part of the neuronal network for respiration is shared by networks for these non-respiratory activities.

Action Potentials↗
PubMed2001

Prospective study of swallowing function in patients with cervical dystonia undergoing selective peripheral denervation.

OBJECTIVE: To characterise swallowing function in patients with cervical dystonia with botulinum toxin treatment failure, before and after selective peripheral denervation surgery. METHODS: Twelve patients with cervical dystonia had a thorough examination including standardised assessment for cervical dystonia, scoring of subjective dysphagia, and videofluoroscopic swallow. Videofluoroscopy was scored by consensus opinion between a speech and language therapist and an independent blinded radiologist using a validated scoring system. RESULTS: Seven patients with cervical dystonia experienced no subjective dysphagia either before or after surgery, although in all these patients there was objective videofluoroscopic evidence of underlying mild to moderate oropharyngeal dysphagia preoperatively and postoperatively. The most common finding was delayed initiation of swallow. Three other patients, also without subjective dysphagia before surgery, developed postoperative dysphagia. In these patients, videofluoroscopy showed a delayed swallow reflex before surgery, which was worse postoperatively in two. The remaining two patients had mild subjective dysphagia before surgery that improved postoperatively in one and deteriorated in the other. In the first, videofluoroscopy was normal preoperatively and postoperatively, and in the second, oral bolus preparation was moderately abnormal preoperatively and swallow initiation was delayed postoperatively. Mean subjective dysphagia scores did not change significantly. Apart from a significant improvement of tongue base retraction, videofluoroscopic scores were not significantly different after surgery. Postoperatively there was significant improvement of overall cervical dystonia severity and abnormal head rotation in the group as a whole. There was no correlation between age, duration of symptoms of cervical dystonia, preoperative or postoperative cervical dystonia severity, subjective dysphagia scores, or videofluoroscopic scores. However, in the five patients with persisting anterior sagittal head shift as part of the torticollis, tongue base retraction was less likely to improve after surgery compared with those without head shift. CONCLUSION: Surgical denervation of dystonic neck muscles, leading to improved neck posture, can also improve tongue base retraction, which is a key component of normal bolus propagation. However, delayed swallow initiation, a common feature in patients with cervical dystonia, can be further compromised by surgery, leading to subjective dysphagia. In general, selective peripheral denervation seems to be a safe procedure with no major compromise of swallowing function.

Adult↗
PubMed2006

Modulation of human cortical swallowing motor pathways after pleasant and aversive taste stimuli.

Human swallowing involves the integration of sensorimotor information with complexities such as taste; however, the interaction between the taste of food and its effects on swallowing control remains unknown. We assessed the effects of pleasant (sweet) and aversive (bitter) tastes on human cortical swallowing motor pathway excitability. Healthy adult male volunteers underwent a transcranial magnetic stimulation (TMS) mapping study (n = 9, mean age: 34 yr) to assess corticobulbar excitability before and up to 60 min after 10-min liquid infusions either 1) as swallowing tasks or 2) delivered directly into the stomach. Infusions were composed of sterile water (neutral), 10% glucose (sweet), and 0.5 mM quinine hydrochloride (bitter). The order of delivery was randomized, and each infusion was given on separate days. Pharyngeal motor-evoked potentials (PMEPs) were recorded from an intraluminal catheter as a measure of corticobulbar excitability and compared using repeated-measures and one-way ANOVA. After the swallowing task (water, glucose, or quinine), repeated-measures ANOVA revealed a significant time interaction across tastants (P </= 0.01). One-way ANOVA for each taste showed changes in PMEP amplitudes for both quinine (P </= 0.001) and glucose (P </= 0.009) solutions but not for water (P = 0.1). Subsequent t-tests showed that glucose and quinine reduced PMEPs by 47% (SD 34) and 37% (SD 54), respectively, at 30 min (P </= 0.03). No changes were observed after the infusion of any solution directly into the stomach (P = 0.51). In conclusion, cortical swallowing pathways are similarly modulated by both sweet and bitter tasting stimuli. Changes likely reflect a close interaction between taste and swallowing activity mediated in the central nervous system.

Adult↗
PubMed2006

Leptin inhibits swallowing in rats.

Swallowing is under the control of premotoneurons located in the medullary solitary tract nucleus. Although rats with transected midbrain do not seek out food, they are able to ingest food present near the mouth, and acute food deprivation induces an increase in food intake. Leptin is a satiety signal that regulates feeding behavior. Because leptin receptors are found within the caudal brainstem, and because food intake is regulated in midbrain transected rats, this study tested the hypothesis that leptin is able to modify the activity of premotoneurons involved in swallowing. Leptin was microinjected at the subpostremal level of the medullary solitary tract nucleus in anesthetized Wistar rats. Electromyographic electrodes in sublingual muscles allowed recording of swallowing induced by stimulation of sensitive fibers of the superior laryngeal nerve. Repeated stimulation induced rhythmic swallowing. Microinjection of leptin (0.1 pg and 0.1 ng) in the swallowing center induced an inhibition of rhythmic swallowing (latency of <30 s) as shown by the reduced number and strength of electromyographic activities, which could last several minutes. The threshold of the leptin-induced inhibition was close to 0.1 pg. Interestingly, the inhibitory effect of leptin was not observed in leptin receptor-deficient Zucker rats. Here we show that, in Wistar rats, leptin already known to modulate the discharge of medullary solitary tract nucleus-sensitive neurons involved in satiety reflexes can also modify the activity of swallowing premotoneurons, thereby inhibiting an essential motor component of feeding behavior.

Animals↗