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Ventral Posteromedial Nucleus
The ventral posteromedial nucleus (VPM) is a nucleus within the ventral posterior nucleus of the thalamus and serves an analogous somatosensory relay role for the ascending trigeminothalamic tracts as its lateral neighbour the ventral posterolateral nucleus serves for dorsal column–medial lemniscus pathway 2nd-order neurons. The term "ventral posteromedial nucleus" was introduced by Le Gros Clark in 1930. Afferents and efferents Orofacial somatosensory The VPM receives second-order general somatic afferent fibers from the ventral trigeminal tract and the dorsal trigeminal tract which convey general somatic sensory information from the face and oral cavity (including touch, pressure, temperature, pain, and propriception). Proprioceptive synapses are situated anteriorly, ones mediating touch in the middle, and nociceptive ones posteriorly. Third-order neurons in turn project to the somatosensory cortex in the postcentral gyrus. Taste The VPM receives second-order tas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Midline Nuclear Group
The midline nuclear group (or midline thalamic nuclei) is a region of the thalamus consisting of the following nuclei: * Paraventricular thalamus, paraventricular nucleus of thalamus (''nucleus paraventricularis thalami'') - not to be confused with paraventricular nucleus of hypothalamus * paratenial nucleus (''nucleus parataenialis'') * nucleus reuniens (also known as the medioventral nucleus) * rhomboidal nucleus (''nucleus commissuralis rhomboidalis'') * subfascicular nucleus (''nucleus subfascicularis'') The List of regions in the human brain#Thalamus, midline nuclei are often called "nonspecific" in that they project widely to the cortex and elsewhere. This has led to the assumption that they may be involved in general functions such as alerting. However, anatomical connections might suggest more specific functions, with the paraventricular and paratenial nuclei involved in viscero-limbic functions, and the reuniens and rhomboid nuclei involved in multimodal sensory processin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Somatic Afferent Fiber
The general somatic afferent fibers (GSA or somatic sensory fibers) are afferent fibers that arise from neurons in sensory ganglia and are found in all the spinal nerves, except occasionally the first cervical. General somatic afferents conduct impulses of pain, touch and temperature from the surface of the body through the dorsal roots to the spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue that extends from the medulla oblongata in the lower brainstem to the lumbar region of the vertebral column (backbone) of vertebrate animals. The center of the spinal c ..., and impulses of muscle sense, tendon sense and joint sense from the deeper structures. See also * Afferent nerve * General visceral afferent fiber (GVA) * Special somatic afferent fiber (SSA) * Special visceral afferent fiber (SVA) References Spinal cord {{Portal bar, Anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinothalamic Tract
The spinothalamic tract is a nerve tract in the anterolateral system in the spinal cord. This tract is an ascending sensory pathway to the thalamus. From the ventral posterolateral nucleus in the thalamus, sensory information is relayed upward to the somatosensory cortex of the postcentral gyrus. The spinothalamic tract consists of two adjacent pathways: anterior and lateral. The anterior spinothalamic tract carries information about crude touch. The lateral spinothalamic tract conveys pain and temperature. In the spinal cord, the spinothalamic tract has somatotopic organization. This is the segmental organization of its cervical, thoracic, lumbar, and sacral components, which is arranged from most medial to most lateral respectively. The pathway crosses over ( decussates) at the level of the spinal cord, rather than in the brainstem like the dorsal column-medial lemniscus pathway and lateral corticospinal tract. It is one of the three tracts which make up the anterola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parabrachial Nucleus
The parabrachial nuclei, also known as the parabrachial complex, are a group of nuclei in the dorsolateral pons that surrounds the superior cerebellar peduncle as it enters the brainstem from the cerebellum. They are named from the Latin term for the superior cerebellar peduncle, the ''brachium conjunctivum''. In the human brain, the expansion of the superior cerebellar peduncle expands the parabrachial nuclei, which form a thin strip of grey matter over most of the peduncle. The parabrachial nuclei are typically divided along the lines suggested by Baxter and Olszewski in humans, into a medial parabrachial nucleus and lateral parabrachial nucleus. These have in turn been subdivided into a dozen subnuclei: the superior, dorsal, ventral, internal, external and extreme lateral subnuclei; the lateral crescent and subparabrachial nucleus (Kolliker-Fuse nucleus) along the ventrolateral margin of the lateral parabrachial complex; and the medial and external medial subnuclei Anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Visceral Afferent Fiber
The general visceral afferent (GVA) fibers conduct sensory impulses (usually pain or reflex sensations) from the internal organs, glands, and blood vessels to the central nervous system. They are considered to be part of the visceral nervous system, which is closely related to the autonomic nervous system, but 'visceral nervous system' and 'autonomic nervous system' are not direct synonyms and care should be taken when using these terms. Unlike the efferent fibers of the autonomic nervous system, the afferent fibers are not classified as either sympathetic or parasympathetic. GVA fibers create referred pain by activating general somatic afferent fibers where the two meet in the posterior grey column. The cranial nerves that contain GVA fibers include the glossopharyngeal nerve (CN IX) and the vagus nerve (CN X). Generally, they are insensitive to cutting, crushing or burning; however, excessive tension in smooth muscle and some pathological conditions produce visceral pain ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gustatory Cortex
The primary gustatory cortex (GC) is a brain structure responsible for the perception of taste. It consists of two substructures: the anterior insula on the insular lobe and the frontal operculum on the inferior frontal gyrus of the frontal lobe. Because of its composition the primary gustatory cortex is sometimes referred to in literature as the AI/FO(Anterior Insula/Frontal Operculum). By using extracellular unit recording techniques, scientists have elucidated that neurons in the AI/FO respond to sweetness, saltiness, bitterness, and sourness, and they code the intensity of the taste stimulus. Role in the taste pathway Like the olfactory system, the taste system is defined by its specialized peripheral receptors and central pathways that relay and process taste information. Peripheral taste receptors are found on the upper surface of the tongue, soft palate, pharynx, and the upper part of the esophagus. Taste cells synapse with primary sensory axons that run in the cho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elsevier
Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell (journal), Cell'', the ScienceDirect collection of electronic journals, ''Trends (journals), Trends'', the ''Current Opinion (Elsevier), Current Opinion'' series, the online citation database Scopus, the SciVal tool for measuring research performance, the ClinicalKey search engine for clinicians, and the ClinicalPath evidence-based cancer care service. Elsevier's products and services include digital tools for Data management platform, data management, instruction, research analytics, and assessment. Elsevier is part of the RELX Group, known until 2015 as Reed Elsevier, a publicly traded company. According to RELX reports, in 2022 Elsevier published more than 600,000 articles annually in over 2,800 journals. As of 2018, its archives contained over 17 million documents and 40,000 Ebook, e-books, with over one b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solitary Nucleus
The solitary nucleus (SN) (nucleus of the solitary tract, nucleus solitarius, or nucleus tractus solitarii) is a series of neurons whose cell bodies form a roughly vertical column of grey matter in the medulla oblongata of the brainstem. Their axons form the bulk of the enclosed solitary tract. The solitary nucleus can be divided into different parts including dorsomedial, dorsolateral, and ventrolateral subnuclei. The solitary nucleus receives general visceral and special visceral inputs from the facial nerve (CN VII), glossopharyngeal nerve (CN IX) and vagus nerve (CN X); it receives and relays stimuli related to taste and visceral sensation. It sends outputs to various parts of the brain, such as the hypothalamus, thalamus, and reticular formation, forming circuits that contribute to autonomic regulation. Cells along the length of the SN are arranged roughly in accordance with function; for instance, cells involved in taste are located in the rostral part, while those rec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Special Visceral Afferent Fiber
Special visceral afferent fibers (SVA) are afferent fibers that develop in association with the gastrointestinal tract. They carry the special sense of taste (gustation). The cranial nerves containing SVA fibers are the facial nerve (VII), the glossopharyngeal nerve (IX), and the vagus nerve (X). The facial nerve receives taste from the anterior 2/3 of the tongue; the glossopharyngeal from the posterior 1/3, and the vagus nerve from the epiglottis. The sensory processes, using their primary cell bodies from the inferior ganglion, send projections to the medulla, from which they travel in the tractus solitarius, later terminating at the rostral nucleus solitarius.Bhatnagar C. Subhash. ''Neuroscience for the study of communicative disorders''. Philadelphia, Pennsylvania. Lippincott Williams & Wilkins, 2002 See also * General somatic afferent fiber (GSA) * General visceral afferent fiber The general visceral afferent (GVA) fibers conduct sensory impulses (usually pain or reflex sen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Postcentral Gyrus
In neuroanatomy, the postcentral gyrus is a prominent gyrus in the lateral parietal lobe of the human brain. It is the location of the primary somatosensory cortex, the main sensory receptive area for the sense of touch. Like other sensory areas, there is a map of sensory space in this location, called the '' sensory homunculus''. The primary somatosensory cortex was initially defined from surface stimulation studies of Wilder Penfield, and parallel surface potential studies of Bard, Woolsey, and Marshall. Although initially defined to be roughly the same as Brodmann areas 3, 1, and 2, more recent work by Kaas has suggested that for homogeny with other sensory fields only area 3 should be referred to as "primary somatosensory cortex", as it receives the bulk of the thalamocortical projections from the sensory input fields. Structure The lateral postcentral gyrus is bounded by: * medial longitudinal fissure medially (to the middle) * central sulcus rostrally (in front) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Somatosensory Cortex
The somatosensory system, or somatic sensory system is a subset of the sensory nervous system. The main functions of the somatosensory system are the perception of external stimuli, the perception of internal stimuli, and the regulation of body position and balance (proprioception). It is believed to act as a pathway between the different sensory modalities within the body. As of 2024 debate continued on the underlying mechanisms, correctness and validity of the somatosensory system model, and whether it impacts emotions in the body. The somatosensory system has been thought of as having two subdivisions; *one for the detection of mechanosensory information related to touch. Mechanosensory information includes that of light touch, vibration, pressure and tension in the skin. Much of this information belongs to the sense of touch which is a general somatic sense in contrast to the special senses of sight, smell, taste, hearing, and balance. * one for the nociception detect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
