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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 -
Cerebellum (London, England) Apr 2024The cerebellum is a key player in many brain functions and a major topic of neuroscience research. However, the cerebellar nuclei (CN), the main output structures of the... (Review)
Review
The cerebellum is a key player in many brain functions and a major topic of neuroscience research. However, the cerebellar nuclei (CN), the main output structures of the cerebellum, are often overlooked. This neglect is because research on the cerebellum typically focuses on the cortex and tends to treat the CN as relatively simple output nuclei conveying an inverted signal from the cerebellar cortex to the rest of the brain. In this review, by adopting a nucleocentric perspective we aim to rectify this impression. First, we describe CN anatomy and modularity and comprehensively integrate CN architecture with its highly organized but complex afferent and efferent connectivity. This is followed by a novel classification of the specific neuronal classes the CN comprise and speculate on the implications of CN structure and physiology for our understanding of adult cerebellar function. Based on this thorough review of the adult literature we provide a comprehensive overview of CN embryonic development and, by comparing cerebellar structures in various chordate clades, propose an interpretation of CN evolution. Despite their critical importance in cerebellar function, from a clinical perspective intriguingly few, if any, neurological disorders appear to primarily affect the CN. To highlight this curious anomaly, and encourage future nucleocentric interpretations, we build on our review to provide a brief overview of the various syndromes in which the CN are currently implicated. Finally, we summarize the specific perspectives that a nucleocentric view of the cerebellum brings, move major outstanding issues in CN biology to the limelight, and provide a roadmap to the key questions that need to be answered in order to create a comprehensive integrated model of CN structure, function, development, and evolution.
Topics: Cerebellar Nuclei; Cerebellum; Neurons
PubMed: 36781689
DOI: 10.1007/s12311-022-01506-0 -
Cerebellum (London, England) Feb 2020The cerebellum is relevant for virtually all aspects of behavior in health and disease. Cerebellar findings are common across all kinds of neuroimaging studies of brain...
The cerebellum is relevant for virtually all aspects of behavior in health and disease. Cerebellar findings are common across all kinds of neuroimaging studies of brain function and dysfunction. A large and expanding body of literature mapping motor and non-motor functions in the healthy human cerebellar cortex using fMRI has served as a tool for interpreting these findings. For example, results of cerebellar atrophy in Alzheimer's disease in caudal aspects of Crus I/II and medial lobule IX can be interpreted by consulting a large number of task, resting-state, and gradient-based reports that describe the functional characteristics of these specific aspects of the cerebellar cortex. Here, we provide a concise summary that outlines organizational principles observed consistently across these studies of normal cerebellar organization. This basic framework may be useful for investigators performing or reading experiments that require a functional interpretation of human cerebellar topography.
Topics: Cerebellar Cortex; Cerebellar Diseases; Cerebellum; Humans; Magnetic Resonance Imaging; Nerve Net
PubMed: 31707620
DOI: 10.1007/s12311-019-01083-9 -
International Journal of Molecular... Aug 2022The medulla oblongata, located in the hindbrain between the pons and the spinal cord, is an important relay center for critical sensory, proprioceptive, and motoric... (Review)
Review
The medulla oblongata, located in the hindbrain between the pons and the spinal cord, is an important relay center for critical sensory, proprioceptive, and motoric information. It is an evolutionarily highly conserved brain region, both structural and functional, and consists of a multitude of nuclei all involved in different aspects of basic but vital functions. Understanding the functional anatomy and developmental program of this structure can help elucidate potential role(s) of the medulla in neurological disorders. Here, we have described the early molecular patterning of the medulla during murine development, from the fundamental units that structure the very early medullary region into 5 rhombomeres (r7-r11) and 13 different longitudinal progenitor domains, to the neuronal clusters derived from these progenitors that ultimately make-up the different medullary nuclei. By doing so, we developed a schematic overview that can be used to predict the cell-fate of a progenitor group, or pinpoint the progenitor domain of origin of medullary nuclei. This schematic overview can further be used to help in the explanation of medulla-related symptoms of neurodevelopmental disorders, e.g., congenital central hypoventilation syndrome, Wold-Hirschhorn syndrome, Rett syndrome, and Pitt-Hopkins syndrome. Based on the genetic defects seen in these syndromes, we can use our model to predict which medullary nuclei might be affected, which can be used to quickly direct the research into these diseases to the likely affected nuclei.
Topics: Animals; Humans; Medulla Oblongata; Mice; Neurons; Rett Syndrome; Rhombencephalon; Spinal Cord
PubMed: 36012524
DOI: 10.3390/ijms23169260 -
Neuroscience May 2021The cerebellum forms regular neural network structures consisting of a few major types of neurons, such as Purkinje cells, granule cells, and molecular layer... (Review)
Review
The cerebellum forms regular neural network structures consisting of a few major types of neurons, such as Purkinje cells, granule cells, and molecular layer interneurons, and receives two major inputs from climbing fibers and mossy fibers. Its regular structures consist of three well-defined layers, with each type of neuron designated to a specific location and forming specific synaptic connections. During the first few weeks of postnatal development in rodents, the cerebellum goes through dynamic changes via proliferation, migration, differentiation, synaptogenesis, and maturation, to create such a network structure. The development of this organized network structure presumably relies on the communication between developing elements in the network, including not only individual neurons, but also their dendrites, axons, and synapses. Therefore, it is reasonable that extracellular signaling via synaptic transmission, secreted molecules, and cell adhesion molecules, plays important roles in cerebellar network development. Although it is not yet clear as to how overall cerebellar development is orchestrated, there is indeed accumulating lines of evidence that extracellular signaling acts toward the development of individual elements in the cerebellar networks. In this article, we introduce what we have learned from many studies regarding the extracellular signaling required for cerebellar network development, including our recent study suggesting the importance of unbiased synaptic inputs from parallel fibers.
Topics: Axons; Cerebellum; Neurons; Purkinje Cells; Synapses
PubMed: 32502568
DOI: 10.1016/j.neuroscience.2020.05.036 -
Physiology & Behavior Sep 2019Glucose is the required metabolic substrate for the brain. Yet the brain stores very little glucose. Therefore, the brain continuously monitors glucose availability to... (Review)
Review
Glucose is the required metabolic substrate for the brain. Yet the brain stores very little glucose. Therefore, the brain continuously monitors glucose availability to detect hypoglycemia and to mobilize system-wide responses to protect and restore euglycemia. Catecholamine (CA) neurons in the hindbrain are critical elements of the brain's glucoregulatory mechanisms. They project widely throughout the brain and spinal cord, innervating sites controlling behavioral, endocrine and visceral responses. Hence, CA neurons are capable of triggering a rapid, coordinated and multifaceted response to glucose challenge. This article reviews experimental data that has begun to elucidate the importance of CA neurons for glucoregulation, the functions of specific CA subpopulations in the ventrolateral medulla, and the extended circuitry through which they engage other levels of the nervous system to accomplish their essential glucoregulatory task. Hopefully, this review also suggests the vast amount of work yet to be done in this area and the justification for engaging in that effort.
Topics: Animals; Glucose; Medulla Oblongata; Neurons; Rhombencephalon
PubMed: 31173784
DOI: 10.1016/j.physbeh.2019.112568 -
Brain Stimulation 2023Low-intensity ultrasound is a noninvasive neuromodulation technique with the potential to focally manipulate deep brain activity at millimeter-scale resolution. However,...
BACKGROUND
Low-intensity ultrasound is a noninvasive neuromodulation technique with the potential to focally manipulate deep brain activity at millimeter-scale resolution. However, there have been controversies over the direct influence of ultrasound on neurons, due to an indirect auditory activation. Besides, the capacity of ultrasound to stimulate the cerebellum remains underestimated.
OBJECTIVE
To validate the direct neuromodulation effects of ultrasound on the cerebellar cortex from both cellular and behavioral levels.
METHODS
Two-photon calcium imaging were used to measure the neuronal responses of cerebellar granule cells (GrCs) and Purkinje cells (PCs) to ultrasound application in awake mice. And a mouse model of paroxysmal kinesigenic dyskinesia (PKD), in which direct activation of the cerebellar cortex leads to dyskinetic movements, was used to assess the ultrasound-induced behavioral responses.
RESULTS
Low-intensity ultrasound stimulus (0.1 W/cm) evoked rapidly increased and sustained neural activity in GrCs and PCs at targeted region, while no significant changes in calcium signals were observed responding to off-target stimulus. The efficacy of ultrasonic neuromodulation relies on acoustic dose modified by ultrasonic duration and intensity. In addition, transcranial ultrasound reliably triggered dyskinesia attacks in proline-rich transmembrane protein 2 (Prrt2) mutant mice, suggesting that the intact cerebellar cortex were activated by ultrasound.
CONCLUSION
Low-intensity ultrasound directly activates the cerebellar cortex in a dose-dependent manner, and thus serves as a promising tool for cerebellar manipulation.
Topics: Mice; Animals; Calcium; Cerebellum; Brain; Neurons; Purkinje Cells
PubMed: 37245844
DOI: 10.1016/j.brs.2023.05.012 -
Neuroscience Feb 2022
Topics: Action Potentials; Cerebellum; Purkinje Cells
PubMed: 35031082
DOI: 10.1016/j.neuroscience.2021.12.007 -
Brain and Nerve = Shinkei Kenkyu No... Mar 2024Based on a recent review by Krohn et al, the respiratory center and its regulatory mechanisms are described. Although the respiratory control centers in the medulla and... (Review)
Review
Based on a recent review by Krohn et al, the respiratory center and its regulatory mechanisms are described. Although the respiratory control centers in the medulla and pons ensure rhythmic respiration, maintaining and regulating respiration involves a complex network of peripheral chemoreceptors, vagal nerves, and central chemoreceptors. This review discusses the pathophysiology of respiratory disorders in neuromuscular diseases and evaluation and treatment methods based on the anatomy of the respiratory network.
Topics: Humans; Respiration; Neuromuscular Diseases; Respiratory Insufficiency; Medulla Oblongata; Pons
PubMed: 38514105
DOI: 10.11477/mf.1416202594 -
Frontiers in Neural Circuits 2022The lateral superior olive (LSO) is a key structure in the central auditory system of mammals that exerts efferent control on cochlear sensitivity and is involved in the...
The lateral superior olive (LSO) is a key structure in the central auditory system of mammals that exerts efferent control on cochlear sensitivity and is involved in the processing of binaural level differences for sound localization. Understanding how the LSO contributes to these processes requires knowledge about the resident cells and their connections with other auditory structures. We used standard histological stains and retrograde tracer injections into the inferior colliculus (IC) and cochlea in order to characterize two basic groups of neurons: (1) Principal and periolivary (PO) neurons have projections to the IC as part of the ascending auditory pathway; and (2) lateral olivocochlear (LOC) intrinsic and shell efferents have descending projections to the cochlea. Principal and intrinsic neurons are intermixed within the LSO, exhibit fusiform somata, and have disk-shaped dendritic arborizations. The principal neurons have bilateral, symmetric, and tonotopic projections to the IC. The intrinsic efferents have strictly ipsilateral projections, known to be tonotopic from previous publications. PO and shell neurons represent much smaller populations (<10% of principal and intrinsic neurons, respectively), have multipolar somata, reside outside the LSO, and have non-topographic, bilateral projections. PO and shell neurons appear to have widespread projections to their targets that imply a more diffuse modulatory function. The somata and dendrites of principal and intrinsic neurons form a laminar matrix within the LSO and share quantifiably similar alignment to the tonotopic axis. Their restricted projections emphasize the importance of frequency in binaural processing and efferent control for auditory perception. This study addressed and expanded on previous findings of cell types, circuit laterality, and projection tonotopy in the LSO of the mouse.
Topics: Animals; Mice; Superior Olivary Complex; Olivary Nucleus; Auditory Pathways; Inferior Colliculi; Neurons; Mammals
PubMed: 36338332
DOI: 10.3389/fncir.2022.1038500