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Reticulospinal
The reticular formation is a set of interconnected nuclei that are located throughout the brainstem. It is not anatomically well defined, because it includes neurons located in different parts of the brain. The neurons of the reticular formation make up a complex set of networks in the core of the brainstem that extend from the upper part of the midbrain to the lower part of the medulla oblongata. The reticular formation includes ascending pathways to the cortex in the ascending reticular activating system (ARAS) and descending pathways to the spinal cord via the reticulospinal tracts. Neurons of the reticular formation, particularly those of the ascending reticular activating system, play a crucial role in maintaining behavioral arousal and consciousness. The overall functions of the reticular formation are modulatory and premotor, involving somatic motor control, cardiovascular control, pain modulation, sleep and consciousness, and habituation. The modulatory functions are prim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Motor Neuron
Alpha (α) motor neurons (also called alpha motoneurons), are large, multipolar lower motor neurons of the brainstem and spinal cord. They innervate extrafusal muscle fibers of skeletal muscle and are directly responsible for initiating their contraction. Alpha motor neurons are distinct from gamma motor neurons, which innervate intrafusal muscle fibers of muscle spindles. While their cell bodies are found in the central nervous system (CNS), α motor neurons are also considered part of the somatic nervous system—a branch of the peripheral nervous system (PNS)—because their axons extend into the periphery to innervate skeletal muscles. An alpha motor neuron and the muscle fibers it innervates is a motor unit. A motor neuron pool contains the cell bodies of all the alpha motor neurons involved in contracting a single muscle. Location Alpha motor neurons (α-MNs) innervating the head and neck are found in the brainstem; the remaining α-MNs innervate the rest of the body and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronal Plane
The coronal plane (also known as the frontal plane) is an anatomical plane that divides the body into dorsal and ventral sections. It is perpendicular to the sagittal and transverse planes. Details The coronal plane is an example of a longitudinal plane. For a human, the mid-coronal plane would transect a standing body into two halves (front and back, or anterior and posterior) in an imaginary line that cuts through both shoulders. The description of the coronal plane applies to most animals as well as humans even though humans walk upright and the various planes are usually shown in the vertical orientation. The sternal plane (''planum sternale'') is a coronal plane which transects the front of the sternum. Etymology The term is derived from Latin ''corona'' ('garland, crown'), from Ancient Greek κορώνη (''korōnē'', 'garland, wreath'). The coronal plane is so-called because it lies in the direction of Coronal suture. Additional images File:Coronal plane CT scan of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gigantocellular Reticular Nuclei
The gigantocellular reticular nucleus (Gi) is a subregion of the medullary reticular formation. As the name indicates, it consists mainly of so-called giant neuronal cells. This nucleus has been known to innervate the caudal hypoglossal nucleus, and responds to glutamatergic stimuli. The gigantocellular nucleus excites the hypoglossal nucleus, and can play a role in the actions of the said nerve.Yang, CC et al. Excitatory innervation of caudal hypoglossal nucleus from nucleus reticularis gigantocellularis in the rat. Neuroscience. 1995 Mar;65(2):365-74. It additionally receives connections from the periaqueductal gray, the paraventricular hypothalamic nucleus, central nucleus of the amygdala, lateral hypothalamic area, and parvocellular reticular nucleus. Retrograde studies have shown that the deep mesencephalic reticular formation and oral pontine reticular nucleus project to the gigantocellular nucleus. The dorsal rostral section of the nucleus reticularis gigantocellularis is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagittal
The sagittal plane (; also known as the longitudinal plane) is an anatomical plane that divides the body into right and left sections. It is perpendicular to the transverse and coronal planes. The plane may be in the center of the body and divide it into two equal parts ( mid-sagittal), or away from the midline and divide it into unequal parts (para-sagittal). The term ''sagittal'' was coined by Gerard of Cremona. Variations in terminology Examples of sagittal planes include: * The terms ''median plane'' or ''mid-sagittal plane'' are sometimes used to describe the sagittal plane running through the midline. This plane cuts the body into halves (assuming bilateral symmetry), passing through midline structures such as the navel and spine. It is one of the planes which, combined with the Umbilical plane, defines the four quadrants of the human abdomen. * The term ''parasagittal'' is used to describe any plane parallel or adjacent to a given sagittal plane. Specific named parasag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systems Neuroscience
Systems neuroscience is a subdiscipline of neuroscience and systems biology that studies the structure and function of neural circuits and systems. Systems neuroscience encompasses a number of areas of study concerned with how nerve cells behave when connected together to form neural pathways, neural circuits, and larger brain networks. At this level of analysis, neuroscientists study how different neural circuits analyze sensory information, form perceptions of the external world, make decisions, and execute movements. Researchers in systems neuroscience are concerned with the relation between molecular and cellular approaches to understanding brain structure and function, as well as with the study of high-level mental functions such as language, memory, and self-awareness (which are the purview of behavioral and cognitive neuroscience). Systems neuroscientists typically employ techniques for understanding networks of neurons as they are seen to function, by way of electrophysi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholinergic Neuron
A cholinergic neuron is a nerve cell which mainly uses the neurotransmitter acetylcholine (ACh) to send its messages. Many neurological systems are cholinergic. Cholinergic neurons provide the primary source of acetylcholine to the cerebral cortex, and promote cortical activation during both wakefulness and rapid eye movement sleep. The cholinergic system of neurons has been a main focus of research in aging and neural degradation, specifically as it relates to Alzheimer's disease. The dysfunction and loss of basal forebrain cholinergic neurons and their cortical projections are among the earliest pathological events in Alzheimer's disease. Anatomy Most research involving cholinergic neurons involves the basal forebrain cholinergic neurons. However, cholinergic neurons only represent about 5% of the total basal forebrain cell population. Most of these neurons originate in different areas of the basal forebrain and have extensive projections into almost all layers of the cortex. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamocortical Radiations
In neuroanatomy, thalamocortical radiations are the fibers between the thalamus and the cerebral cortex. Structure Thalamocortical (TC) fibers have been referred to as one of the two constituents of the isothalamus, the other being micro neurons. Thalamocortical fibers have a bush or tree-like appearance as they extend into the internal capsule and project to the layers of the cortex. The main thalamocortical fibers extend from different nuclei of the thalamus and project to the visual cortex, somatosensory (and associated sensori-motor) cortex, and the auditory cortex in the brain. Thalamocortical radiations also innervate gustatory and olfactory pathways, as well as pre-frontal motor areas. Visual input from the optic tract is processed by the lateral geniculate nucleus of the thalamus, auditory input in the medial geniculate nucleus, and somatosensory input in the ventral posterior nucleus of the thalamus. Thalamic nuclei project to cortical areas of distinct architectural or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reticular Nuclei
Reticular nucleus may refer to: * Caudal pontine reticular nucleus * Gigantocellular reticular nucleus, a nucleus that innervates the caudal hypoglossal nucleus, and responds to glutamateric stimuli. * Lateral reticular nucleus * Oral pontine reticular nucleus * Paramedian reticular nucleus, a nucleus that mediate the horizontal eye movements on their ipsilateral sides * Parvocellular reticular nucleus, part of the brain located dorsolateral to the caudal pontine reticular nucleus * Tegmental pontine reticular nucleus, an area within the floor of the midbrain * Thalamic reticular nucleus The thalamic reticular nucleus is part of the ventral thalamus that forms a capsule around the thalamus laterally. However, recent evidence from mice and fish question this statement and define it as a dorsal thalamic structure. It is separated fro ..., part of the ventral thalamus that forms a capsule around the thalamus laterally * Ventral reticular nucleus, a continuation of the parvocellula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellum
The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebellum plays an important role in motor control. It may also be involved in some cognition, cognitive functions such as attention and language as well as emotion, emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to Motor coordination, coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity. Cerebellar damage produces disorders in Fine motor skill, fine movement, Equilibrioception, equilibrium, Human positions, posture, and motor learning in humans. Anatomica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forebrain
In the anatomy of the brain of vertebrates, the forebrain or prosencephalon is the Anatomical terms of location#Directional terms, rostral (forward-most) portion of the brain. The forebrain (prosencephalon), the midbrain (mesencephalon), and hindbrain (rhombencephalon) are the three Brain vesicle, primary brain vesicles during the early development of the nervous system. The forebrain controls body temperature, reproductive functions, eating, sleeping, and the display of emotions. At the five-vesicle stage, the forebrain separates into the diencephalon (thalamus, hypothalamus, subthalamus, and epithalamus) and the telencephalon which develops into the cerebrum. The cerebrum consists of the cerebral cortex, underlying white matter, and the basal ganglia. In humans, by 5 weeks in utero it is visible as a single portion toward the front of the fetus. At 8 weeks in utero, the forebrain splits into the left and right cerebral hemispheres. When the embryonic forebrain fails to divide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain Nuclei
In neuroanatomy, a nucleus (plural form: nuclei) is a cluster of neurons in the central nervous system, located deep within the cerebral hemispheres and brainstem. The neurons in one nucleus usually have roughly similar connections and functions. Nuclei are connected to other nuclei by tracts, the bundles (fascicles) of axons (nerve fibers) extending from the cell bodies. A nucleus is one of the two most common forms of nerve cell organization, the other being layered structures such as the cerebral cortex or cerebellar cortex. In anatomical sections, a nucleus shows up as a region of gray matter, often bordered by white matter. The vertebrate brain contains hundreds of distinguishable nuclei, varying widely in shape and size. A nucleus may itself have a complex internal structure, with multiple types of neurons arranged in clumps (subnuclei) or layers. The term "nucleus" is in some cases used rather loosely, to mean simply an identifiably distinct group of neurons, even if they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lower Pons Horizontal KB
Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Lower Wick is a small hamlet located in the county of Gloucestershire, England. It is situated about five miles south west of Dursley, eighteen miles southwest of Gloucester and fifteen miles northeast of Bristol. Lower Wick is within the civil ... Gloucestershire, England See also * Nizhny {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
