The ventral shaft of the spine, unlike the dorsal shaft, has the main function of emitting information to the nerves, causing the body to react to external or internal stimuli. Squire, L. R.; Floyd Bloom, N. S. (2008). The anterior aspect of the spinal cord contains, in its midline, an anterior medial groove, which borders laterally with the anterior collateral grooves. The White matter Of the spinal cord is characterized by surrounding the gray matter. In this sense, lesions in the cervical vertebrae four and seven have been found to cause paralysis of the four extremities, and involvement of the eleventh vertebra of the thorax causes paralysis of the lower limbs. These are: the pia mater, the arachnoid and the dura mater. The spinal cord is contained in the center cavity of the vertebral column (back bone) which protects the spinal cord from injury. Like the brain, the spinal cord is covered by three layers of tissue (meninges). Spinal cord (diagram) The spinal cord is a continuation of the brainstem.It extends from the foramen magnum at the base of the skull to the L1/L2 vertebra where it terminates as the conus medullaris (medullary cone). In most adults, the spine is composed of 33 individual back bones (vertebrae). This part of the spine contains no actual segments of the spinal cord. A lot of the time it's due to damage on the spinal cord. In this way, the spinal cord of a newborn reaches the lumbar vertebrae three and in the embryos the spinal cord is found until the base of the coccyx of the body. One point to note is the presence of two areas in which the medulla is somewhat wider, because in these areas are the nerve connections with the extremities. The grey substance has this coloration because it is a set of somas or nuclei of neurons, which project their axons to other areas. Finally, in the lateral part of the base of the posterior horn of the upper cervical segments is a region called Reticular formation . (2002) Physiology of the autonomic nervous system. The cervical spinal cord: This is the topmost portion of the spinal cord, where the brain connects to the spinal cord, and the neck connects to the back. Editorial Médica Panamericana. It is established that it is one of the most important and committed regions of the body. Fundamental Neuroscience (Digitised online by Googlebooks). These neurons participate in two modes of conscious proprioception: kinesthesia and epicritic touch. This division of the commissure is made by a small central hole called the ependymal conduit or spinal cord. In this sense, the main function of the posterior horns (those furthest from the skull) is to receive stimuli and transmit them to the brain regions. It carries messages that coordinate movement and sensation. (2008). The spinal cord is a long, fragile tubelike structure that begins at the end of the brain stem and continues down almost to the bottom of the spine. However, it may be of interest to analyze the internal structure of the spinal cord. This latter region of the marrow is called the terminal cone. In this way, actions are programmed into the design of the spinal cord, and are always executed in the same way. In general, the nerve connections correspond to the area where they are located. Communication between agency and brain Is performed by two main transmission mechanisms: the afferent function that sends nerve impulses from the trunk, neck and limbs to the brain and efferent function that carries signals from the brain to different regions of the body. In this case we are talking about primitive reflexes, the absence of which may be a sign of illness. The thickening is formed by the roots of nerves that transmit sensitivity and motor action from the upper limbs. This membrane is formed by an external and homogeneous sheet, as well as an inner areolar layer containing large meshes and constituting the subarachnoid space. Vol.2, Angiology-Central Nervous System (9th edition). Advertisement. These types of cells are organized differently in each region of the spinal cord. In contrast, it adopts an ovoid shape with a transverse diameter greater than the obverse in the lower cervical and thoracic segments. In the lateral pates, the spinal cord has as a fixation element to dentate ligaments. In other words, it is the part of the spinal cord that ensures that the external or internal stimulation detected by the receptors can be sent to the brain. Instead, in the lateral sense, it extends around each spinal nerve. In the intermediate layer of the gray matter, only upper thoracic and lumbar segments of the spinal cord are found. The white matter consists of myelinated fibres, or axons, that form nerve tracts ascending to and descending from the brain. Neuropsychology and behavioral neurology. The spinal cord comprises three parts: the cervical (neck), thoracic (chest), and lumbar (lower back) regions. The medullary lesion can generate several symptoms, the main ones being: paralysis or loss of sensitivity in muscles of the trunk, neck and extremities, vesical, anal or seminal sphincter disorders and sympathetic system block, causing hypotension, bradycardia or abdominal distension. On the other hand, it must be taken into account that the spinal cord is an asymmetrical structure in most people. Game Points. Junqué, C. I Barroso, J (2009). The effects of myelopathy may depend on the degree of damage to the spinal cord, resulting in complete injury (if all symptoms of the disease occur) or incomplete injury (if only a few). This means that both when the brain gives the order for an action to be performed (e.g. The back of the outer surface of this membrane is in contact with the posterior longitudinal ligament. Sacral spinal cord injury S1-S5 The sacral spine is the very base of the spinal column—a triangular bone at the end between the lumbar spine and the tailbone. Ascending axons are responsible for driving pain, temperature and thick touch. 2nd edition. Being the second most important and complementary part of CNS (Central Nervous System), it not only connects the brain with PNS (Peripheral Nervous System), but also performs a multitude of essential neural functions in your body. 100: 297-379. The spinal cord is the neurological pathway for sending and receiving signals to and from the brain. Ediciones Díaz de Santos. The white matter of the spinal cord is formed by the axons of the neurons (not the nuclei). It constitutes a hollow cylinder that is formed mainly by a fibrous wall, thick, solid and little extensible. The spinal cord contains three membranes that wrap around its structure. On the other hand, spinal cord injuries, whether due to myelopathy or trauma in the spinal cord regions, vary markedly depending on the affected region. J Comp Neurol. This region contains two anterior gray horns and two gray posterior horns, which are united by a gray commissure. The spinal cord consists of nerves that carry incoming and outgoing messages between the brain and the rest of the body. There are two enlargements, the cervical and the lumbar. The anterior aspect of the spinal cord contains, in its midline, an anterior medial groove, which borders laterally with the anterior collateral grooves. Academic Press. Buenos Aires: El Ateneo. A cytoarchitectonic atlas of the spinal cord in the cat. Specifically, it slides from the Medulla bulb of the Trunk of the brain (Brain) to the lumbar region. That extends inferiorly from the brain, vertebrae protect the spinal cord from injury not the ). 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