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The Journals of Gerontology. Series A,... Jan 2021The purpose of this investigation was to determine the effects of vocal training on neuromuscular junction (NMJ) morphology and muscle fiber size and composition in the...
The purpose of this investigation was to determine the effects of vocal training on neuromuscular junction (NMJ) morphology and muscle fiber size and composition in the thyroarytenoid muscle, the primary muscle in the vocal fold, in younger (9-month) and older (24-month) Fischer 344 × Brown Norway male rats. Over 4 or 8 weeks of vocal training, rats of both ages progressively increased their daily number of ultrasonic vocalizations (USVs) through operant conditioning and were then compared to an untrained control group. Neuromuscular junction morphology and myofiber size and composition were measured from the thyroarytenoid muscle. Acoustic analysis of USVs before and after training quantified the functional effect of training. Both 4- and 8-week training resulted in less NMJ motor endplate dispersion in the lateral portion of the thyroarytenoid muscle in rats of both ages. Vocal training and age had no significant effects on laryngeal myofiber size or type. Vocal training resulted in a greater number of USVs with longer duration and increased intensity. This study demonstrated that vocal training induces laryngeal NMJ morphology and acoustic changes. The lack of significant effects of vocal training on muscle fiber type and size suggests vocal training significantly improves neuromuscular efficiency but does not significantly influence muscle strength changes.
Topics: Acoustics; Aging; Animals; Female; Laryngeal Muscles; Male; Motor Endplate; Muscle Fibers, Skeletal; Neuromuscular Junction; Rats; Rats, Inbred BN; Rats, Inbred F344; Ultrasonics; Vocalization, Animal
PubMed: 32738046
DOI: 10.1093/gerona/glaa173 -
The Journal of Neuroscience : the... Jan 2020In many species, vocal communication is essential for coordinating social behaviors including courtship, mating, parenting, rivalry, and alarm signaling. Effective... (Review)
Review
In many species, vocal communication is essential for coordinating social behaviors including courtship, mating, parenting, rivalry, and alarm signaling. Effective communication requires accurate production, detection, and classification of signals, as well as selection of socially appropriate responses. Understanding how signals are generated and how acoustic signals are perceived is key to understanding the neurobiology of social behaviors. Here we review our long-standing research program focused on , a frog genus which has provided valuable insights into the mechanisms and evolution of vertebrate social behaviors. In , vocal signals differ between the sexes, through development, and across the genus, reflecting evolutionary divergence in sensory and motor circuits that can be interrogated mechanistically. Using two preparations, the isolated brain and vocal organ, we have identified essential components of the vocal production system: the sexually differentiated larynx at the periphery, and the hindbrain vocal central pattern generator (CPG) centrally, that produce sex- and species-characteristic sound pulse frequencies and temporal patterns, respectively. Within the hindbrain, we have described how intrinsic membrane properties of neurons in the vocal CPG generate species-specific vocal patterns, how vocal nuclei are connected to generate vocal patterns, as well as the roles of neurotransmitters and neuromodulators in activating the circuit. For sensorimotor integration, we identified a key forebrain node that links auditory and vocal production circuits to match socially appropriate vocal responses to acoustic features of male and female calls. The availability of a well supported phylogeny as well as reference genomes from several species now support analysis of the genetic architecture and the evolutionary divergence of neural circuits for vocal communication. thus provides a vertebrate model in which to study vocal communication at many levels, from physiology, to behavior, and from development to evolution. As one of the most comprehensively studied phylogenetic groups within vertebrate vocal communication systems, provides insights that can inform social communication across phyla.
Topics: Acoustic Stimulation; Animal Communication; Animals; Arytenoid Cartilage; Biological Evolution; Central Pattern Generators; Female; Gonadal Steroid Hormones; In Vitro Techniques; Laryngeal Muscles; Laryngeal Nerves; Male; Medulla Oblongata; Nerve Net; Neurotransmitter Agents; Rhombencephalon; Sex Characteristics; Sexual Behavior, Animal; Social Behavior; Species Specificity; Vocalization, Animal; Xenopus laevis
PubMed: 31896561
DOI: 10.1523/JNEUROSCI.0736-19.2019 -
The Annals of Otology, Rhinology, and... Mar 2022(1) Determine the feasibility of obtaining a global, unbiased metabolomic profile on laryngeal muscle in a rat model; (2) evaluate the impact of biological aging on the...
OBJECTIVES
(1) Determine the feasibility of obtaining a global, unbiased metabolomic profile on laryngeal muscle in a rat model; (2) evaluate the impact of biological aging on the laryngeal metabolome; and (3) characterize biochemical expression differences between aged and non-aged laryngeal and hindlimb muscle.
METHODS
Thyroarytenoid laryngeal muscle and plantaris hindlimb muscle were harvested from 5 young adult (9 months old) and 5 older adult (32 months old) F344BN rats. Tissue was processed and analyzed using LC-MS methods. Detected metabolites were compared to widely used metabolite databases and KEGG pathway enrichment was performed on significant metabolites.
RESULTS
The greatest differences in metabolite expression were between laryngeal and limb muscle with 126 different metabolites found between laryngeal and limb within the young group and 149 different metabolites within the old group. Significant hits between muscle groups highlighted amino acid differences between these tissues. There were more robust differences with age in limb muscle compared to laryngeal muscle.
CONCLUSIONS
Amino acid metabolism is a key difference between muscles of the limbs and larynx. Due to the number of differentially expressed metabolites between the 2 muscle groups, caution should be exercised when applying skeletal limb muscle physiology and biology concepts to the vocal muscles in both aged and non-aged musculoskeletal systems. Mechanisms underlying less robust effects of age on laryngeal muscle compared to limb muscle require elucidation.
Topics: Age Factors; Aging; Animals; Chromatography, Liquid; Feasibility Studies; Hindlimb; Laryngeal Muscles; Metabolomics; Models, Animal; Muscle, Skeletal; Pilot Projects; Rats; Rats, Inbred F344; Tandem Mass Spectrometry
PubMed: 34041924
DOI: 10.1177/00034894211014692 -
PloS One 2022During the early stages, Parkinson's disease (PD) is well recognized as an asymmetric disease with unilateral onset of resting tremor with varying degrees of rigidity,...
INTRODUCTION
During the early stages, Parkinson's disease (PD) is well recognized as an asymmetric disease with unilateral onset of resting tremor with varying degrees of rigidity, and bradykinesia. However, it remains unknown if other impairments, such as swallowing impairment (i.e., dysphagia), also present asymmetrically.
PURPOSE
The primary aim of this study was to examine muscle activity associated with swallow on the most affected side (MAS) and least affected side (LAS) in persons with PD. A secondary aim was to explore the relationship between differences in muscle activity associated with swallow and subjective reports of swallowing impairment and disease severity.
METHODS
Function of muscles associated with swallowing was assessed using surface electromyography placed over the right and left submental and laryngeal regions during three swallows for a THIN and THICK condition. The Swallowing Quality of Life (SWAL-QOL) questionnaire and the Unified Parkinson's Disease Rating Scale (UPDRS) were collected as measures of subjective swallow impairment and disease severity, respectively.
RESULTS
Thirty-five participants diagnosed with idiopathic PD and on a stable antiparkinsonian medication regimen completed this study. Results revealed no significant mean difference in muscle activity during swallow between the more and less affected side. For the laryngeal muscle region, a significant difference in coefficient of variation between the MAS and LAS was revealed for peak amplitude for the THIN swallow condition. For the laryngeal muscle region, a significant association was revealed between muscle activity and disease severity but not subjective reports of swallowing impairment.
CONCLUSION
Superficially it appears that swallowing impairment present symmetrical during the early stages of PD, however, our variability data indicates otherwise. These results will be used to inform future studies in specific types of swallowing impairment (i.e., oral dysphagia, pharyngeal dysphagia, and esophageal dysphagia), disease progression, and overall asymmetry.
Topics: Aged; Deglutition; Deglutition Disorders; Electromyography; Female; Humans; Laryngeal Muscles; Male; Middle Aged; Parkinson Disease; Quality of Life; Severity of Illness Index; Surveys and Questionnaires
PubMed: 35180221
DOI: 10.1371/journal.pone.0262424 -
Journal of Visualized Experiments : JoVE Apr 2020Electromyography (EMG) measures the muscle response to electrical stimulation or spontaneous activity of motor units and plays an important role in assessing...
Electromyography (EMG) measures the muscle response to electrical stimulation or spontaneous activity of motor units and plays an important role in assessing neuromuscular function. Chronic recording of EMG activity reflecting a muscle's reinnervation status after nerve injury has been limited, due to the invasive nature of traditional EMG recording techniques. In this regard, an implantable system is designed for long-term, in vivo EMG recording and nerve stimulation. It has been applied and tested in a study on reinnervation of laryngeal muscles. This system consists of 1) two bipolar electrode nerve cuffs and leads for stimulating each of two nerves: the recurrent laryngeal nerve (RLN) and internal branch of the superior laryngeal nerve (SLN); 2) two EMG recording electrodes and leads for each of the two laryngeal muscles: posterior cricoarytenoid (PCA) muscle and thyroarytenoid-lateral cricoarytenoid (TA-LCA) muscle complex; and 3) a skin receptacle interfacing all implanted lead terminals to an external recording preamplifier and stimulator using a connection cable. The wire leads are Teflon-coated, multi-filament, type 316 stainless steel. They are coiled and can stretch during body movement of the awake animal to prevent lead breakage and electrode migration. This system is implanted during an aseptic surgery. Afterwards, baseline EMG recordings are performed before the RLN is transected in the second surgery to study muscle reinnervation. Throughout the study, multiple physiological sessions are conducted in the anesthetized animal to obtain evoked and spontaneous EMG activity that reflects the reinnervation status of laryngeal muscles. The system is compact, free of infection over the course of the study, and highly durable. This implantable system can provide a reliable platform for research in which long-term recording or nerve stimulation is required in an anesthetized or freely moving animal.
Topics: Animals; Electric Stimulation; Electrodes, Implanted; Electromyography; Laryngeal Muscles; Neuromuscular Monitoring; Prostheses and Implants; Recurrent Laryngeal Nerve
PubMed: 32391811
DOI: 10.3791/60345 -
Journal of Clinical Neurophysiology :... Aug 2015This review of the central nervous control systems for voice and swallowing has suggested that the traditional concepts of a separation between cortical and limbic and... (Review)
Review
This review of the central nervous control systems for voice and swallowing has suggested that the traditional concepts of a separation between cortical and limbic and brain stem control should be refined and be more integrative. For voice production, a separation of the nonhuman vocalization system from the human learned voice production system has been posited based primarily on studies of nonhuman primates. However, recent humans studies of emotionally based vocalizations and human volitional voice production have shown more integration between these two systems than previously proposed. Recent human studies have shown that reflexive vocalization as well as learned voice production not involving speech involve a common integrative system. However, recent studies of nonhuman primates have provided evidence that some cortical activity vocalization and cortical changes occur with training during vocal behavior. For swallowing, evidence from the macaque and functional brain imaging in humans indicates that the control for the pharyngeal phase of swallowing is not primarily under brain stem mechanisms as previously proposed. Studies suggest that the initiation and patterning of swallowing for the pharyngeal phase is also under active cortical control for both spontaneous as well as volitional swallowing in awake humans and nonhuman primates.
Topics: Animals; Central Nervous System; Deglutition; Humans; Laryngeal Muscles; Voice
PubMed: 26241238
DOI: 10.1097/WNP.0000000000000186 -
Journal of Applied Physiology... Feb 2014The upper airway is a complex muscular tube that is used by the respiratory and digestive systems. The upper airway is invested with several small and anatomically... (Review)
Review
The upper airway is a complex muscular tube that is used by the respiratory and digestive systems. The upper airway is invested with several small and anatomically peculiar muscles. The muscle fiber orientations and their nervous innervation are both extremely complex, and how the activity of the muscles is initiated and adjusted during complex behaviors is poorly understood. The bulk of the evidence suggests that the entire assembly of tongue and laryngeal muscles operate together but differently during breathing and swallowing, like a ballet rather than a solo performance. Here we review the functional anatomy of the tongue and laryngeal muscles, and their neural innervation. We also consider how muscular activity is altered as respiratory drive changes, and briefly address upper airway muscle control during swallowing.
Topics: Animals; Deglutition; Humans; Laryngeal Muscles; Pharyngeal Muscles; Respiration; Respiratory Mechanics; Tongue
PubMed: 24092695
DOI: 10.1152/japplphysiol.00670.2013 -
Journal of Neurophysiology Dec 2020Understanding the interactions between neural and musculoskeletal systems is key to identifying mechanisms of functional failure. Mammalian swallowing is a complex,...
Understanding the interactions between neural and musculoskeletal systems is key to identifying mechanisms of functional failure. Mammalian swallowing is a complex, poorly understood motor process. Lesion of the recurrent laryngeal nerve, a sensory and motor nerve of the upper airway, results in airway protection failure (liquid entry into the airway) during swallowing through an unknown mechanism. We examined how muscle and kinematic changes after recurrent laryngeal nerve lesion relate to airway protection in eight infant pigs. We tested two hypotheses: ) kinematics and muscle function will both change in response to lesion in swallows with and without airway protection failure, and ) differences in both kinematics and muscle function will predict whether airway protection failure occurs in lesion and intact pigs. We recorded swallowing with high-speed videofluoroscopy and simultaneous electromyography of oropharyngeal muscles pre- and postrecurrent laryngeal nerve lesion. Lesion changed the relationship between airway protection and timing of tongue and hyoid movements. Changes in onset and duration of hyolaryngeal muscles postlesion were less associated with airway protection outcomes. The tongue and hyoid kinematics all predicted airway protection outcomes differently pre- and postlesion. Onset and duration of activity in only one infrahyoid and one suprahyoid muscle showed a change in predictive relationship pre- and postlesion. Kinematics of the tongue and hyoid more directly reflect changes in airway protections pre- and postlesion than muscle activation patterns. Identifying mechanisms of airway protection failure requires specific functional hypotheses that link neural motor outputs to muscle activation to specific movements. Kinematic and muscle activity patterns of oropharyngeal structures used in swallowing show different patterns of response to lesion of the recurrent laryngeal nerve. Understanding how muscles act on structures to produce behavior is necessary to understand neural control.
Topics: Animals; Biomechanical Phenomena; Deglutition; Electromyography; Fluoroscopy; Laryngeal Muscles; Laryngeal Nerves; Neck Muscles; Pharyngeal Muscles; Swine
PubMed: 32966748
DOI: 10.1152/jn.00409.2020 -
Proceedings of the National Academy of... May 2022Marmosets display remarkable vocal motor abilities. Macaques do not. What is it about the marmoset brain that enables its skill in the vocal domain? We examined the...
Marmosets display remarkable vocal motor abilities. Macaques do not. What is it about the marmoset brain that enables its skill in the vocal domain? We examined the cortical control of a laryngeal muscle that is essential for vocalization in both species. We found that, in both monkeys, multiple premotor areas in the frontal lobe along with the primary motor cortex (M1) are major sources of disynaptic drive to laryngeal motoneurons. Two of the premotor areas, ventral area 6 (area 6V) and the supplementary motor area (SMA), are a substantially larger source of descending output in marmosets. We propose that the enhanced vocal motor skills of marmosets are due, in part, to the expansion of descending output from these premotor areas.
Topics: Animals; Brain Mapping; Haplorhini; Laryngeal Muscles; Motor Cortex; Vocalization, Animal
PubMed: 35507879
DOI: 10.1073/pnas.2122345119 -
Ear, Nose, & Throat Journal Mar 2022Arytenoid dislocation and subluxations commonly are reduced surgically using Holinger and straight Miller-3 laryngoscopes. We present a case of arytenoid cartilage...
Arytenoid dislocation and subluxations commonly are reduced surgically using Holinger and straight Miller-3 laryngoscopes. We present a case of arytenoid cartilage subluxation returned to good position using a 28-Jackson dilator. A 66-year-old man was diagnosed previously with right vocal fold paresis and left vocal fold paralysis following a motor vehicle accident that required a 14-day intubation and tracheotomy maintained for 3 weeks. Evaluation by strobovideolaryngoscopy 3 months following the accident showed severe left vocal fold hypomotility and arytenoid height disparity; laryngeal electromyography showed only mild-to-moderate decreased recruitment in laryngeal muscles. No abnormalities were appreciated on neck computed tomography. Upon palpation of both arytenoid cartilages in the operating room, the left joint was found to be subluxed anteriorly and immobile. A 28-Jackson dilator was used to mobilize and reduce the left arytenoid cartilage, and steroid was injected into the cricothyroid joint. Increased mobility was obtained in the operating room and the patient reported significant improvement in his voice. Six months later, we saw improvement in arytenoid height disparity and left vocal fold movement, better glottic closure, and voice handicap index was improved. A 28-Jackson dilator can be used to manipulate the cricoarytenoid joint without trauma to the vocal process.
Topics: Aged; Arytenoid Cartilage; Humans; Laryngeal Muscles; Laryngoscopes; Male; Vocal Cord Paralysis; Vocal Cords
PubMed: 32804570
DOI: 10.1177/0145561320946901