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Ventral Nuclear Group
The ventral nuclear group is a collection of nuclei on the ventral side of the thalamus The thalamus (: thalami; from Greek language, Greek Wikt:θάλαμος, θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the wikt:dorsal, dorsal part of the diencephalon (a division of ..., it consists of the following: * ventral anterior nucleus * ventral lateral nucleus * ventral posterior nucleus – this is made up of two nuclei: the ventral posterolateral nucleus and the ventral posteromedial nucleus See also * Anterolateral region of the motor thalamus References Thalamus {{Neuroanatomy-stub ... [...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] |
Lateral Geniculate Nucleus
In neuroanatomy, the lateral geniculate nucleus (LGN; also called the lateral geniculate body or lateral geniculate complex) is a structure in the thalamus and a key component of the mammalian visual pathway. It is a small, ovoid, Anatomical terms of location#Dorsal_and_ventral, ventral projection of the thalamus where the thalamus connects with the optic nerve. There are two LGNs, one on the left and another on the right side of the thalamus. In humans, both LGNs have six layers of neurons (grey matter) alternating with optic fibers (white matter). The LGN receives information directly from the ascending retinal ganglion cells via the optic tract and from the reticular activating system. Neurons of the LGN send their axons through the optic radiation, a direct pathway to the primary visual cortex. In addition, the LGN receives many strong feedback connections from the primary visual cortex. In humans as well as other mammals, the two strongest pathways linking the eye to the bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Ventral Posterolateral Nucleus
The ventral posterolateral nucleus (VPL) is one of the subdivisions of the ventral posterior nucleus in the ventral nuclear group of the thalamus. It relays sensory information from the second-order neurons of the neospinothalamic tract and medial lemniscus (of the dorsal column-medial lemniscus pathway) which synapse with the third-order neurons in the nucleus. These then project to the primary somatosensory cortex in the postcentral gyrus. There is uncertainty regarding the location of VMpo (posterior part of ventral medial nucleus), as determined by spinothalamic tract (STT) terminations and staining for calcium-binding proteins, and several authorities do not consider its existence as being proved. The term "ventral posterolateral nucleus" was introduced by Le Gros Clark in 1930. Anatomy Subdivisions The oral part of the ventral posterolateral nucleus (nucleus ventrointermedius) in the human, (VPLO) is a subdivision of the VPL with projections to the motor cortex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Posterior Nucleus
The ventral posterior nucleus is the somatosensory relay nucleus in thalamus of the brain. Input and output The ventral posterior nucleus receives neuronal input from the medial lemniscus, spinothalamic tracts, and trigeminothalamic tract. It projects to the somatosensory cortex and the ascending reticuloactivation system. Subdivisions The ventral posterior nucleus is divided into: *Ventral posterolateral nucleus, which receives sensory information from the body via the medial lemniscus, and spinothalamic tracts. *Ventral posteromedial nucleus, which receives sensory information from the head and face via the trigeminal nerve. *Ventral intermediate nucleus, implicated in oscillatory tremor generation in Parkinson's disease and essential tremor. Function The ventral posterior nucleus has, by virtue of its afferent and efferent pathways, crucial relay and regulatory roles in touch, body position, pain, temperature, itch, taste, and arousal. Additionally, the VPN—and particul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Lateral Nucleus
The ventral lateral nucleus (VL) is a nucleus in the ventral nuclear group of the thalamus. Inputs and outputs It receives neuronal inputs from the basal ganglia which includes the substantia nigra and the globus pallidus (via the thalamic fasciculus). It also has inputs from the cerebellum (via the dentatothalamic tract). It sends neuronal output to the primary motor cortex and premotor cortex. The ventral lateral nucleus in the thalamus forms the motor functional division in the thalamic nuclei along with the ventral anterior nucleus. The ventral lateral nucleus receives motor information from the cerebellum and the globus pallidus. Output from the ventral lateral nucleus then goes to the primary motor cortex. Functions The function of the ventral lateral nucleus is to target efferents including the motor cortex, premotor cortex, and supplementary motor cortex. Therefore, its function helps the coordination and planning of movement. It also plays a role in the learn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Anterior Nucleus
The ventral anterior nucleus (VA) is a nucleus in the ventral nuclear group of the thalamus. It acts with the anterior part of the ventral lateral nucleus to modify signals from the basal ganglia. Inputs and outputs The ventral anterior nucleus receives neuronal inputs from the basal ganglia. Its main afferent fibres are from the globus pallidus. The efferent fibres from this nucleus pass into the premotor cortex The premotor cortex is an area of the motor cortex lying within the frontal lobe of the brain just anterior to the primary motor cortex. It occupies part of Brodmann's area 6. It has been studied mainly in primates, including monkeys and human ... for initiation and planning of movement. Functions It helps to function in movement by providing feedback for the outputs of the basal ganglia. Additional images File:Constudthal.gif, Thalamus File:Territoriostalamo.svg, Thalamus References {{DEFAULTSORT:Ventral Anterior Nucleus Thalamus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamus
The thalamus (: thalami; from Greek language, Greek Wikt:θάλαμος, θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the wikt:dorsal, dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, known as the thalamocortical radiations, allowing hub (network science), hub-like exchanges of information. It has several functions, such as the relaying of sensory neuron, sensory and motor neuron, motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness. Anatomically, the thalami are paramedian symmetrical structures (left and right), within the vertebrate brain, situated between the cerebral cortex and the midbrain. It forms during embryonic development as the main product of the diencephalon, as first recognized by the Swiss embryologist and anatomist Wilhelm His Sr. in 1893. Anatomy The thalami ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medial Geniculate Nucleus
The medial geniculate nucleus (MGN) or medial geniculate body (MGB) is part of the auditory thalamus and represents the thalamic relay between the inferior colliculus (IC) and the auditory cortex (AC). It is made up of a number of sub-nuclei that are distinguished by their neuronal morphology and density, by their afferent and efferent connections, and by the coding properties of their neurons. It is thought that the MGN influences the direction and maintenance of attention. Divisions The MGN has three major divisions; ventral (VMGN), dorsal (DMGN) and medial (MMGN). Whilst the VMGN is specific to auditory information processing, the DMGN and MMGN also receive information from non-auditory pathways. Ventral subnucleus Cell types There are two main cell types in the ventral subnucleus of the medial geniculate body (VMGN): * Thalamocortical relay cells (or principal neurons): The dendritic input to these cells comes from two sets of dendritic trees oriented on opposite poles of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metathalamus
The thalamus (: thalami; from Greek θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, known as the thalamocortical radiations, allowing hub-like exchanges of information. It has several functions, such as the relaying of sensory and motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness. Anatomically, the thalami are paramedian symmetrical structures (left and right), within the vertebrate brain, situated between the cerebral cortex and the midbrain. It forms during embryonic development as the main product of the diencephalon, as first recognized by the Swiss embryologist and anatomist Wilhelm His Sr. in 1893. Anatomy The thalami are paired structures of gray matter about four centimetres long and ovoid in appearance, lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Nuclei Of Thalamus
The anterior nuclei of thalamus (or anterior nuclear group) are a collection of nuclei at the rostral end of the dorsal thalamus. They comprise the anteromedial, anterodorsal, and anteroventral nuclei. Inputs and outputs The anterior nuclei receive afferents from the hippocampus and subiculum directly via the fornix, and indirectly via the mammillary bodies and mammillothalamic tract (MTT). They send efferent fibers to the cingulate gyrus, limbic, and orbitofrontal cortex. The anterior nuclei of the thalamus display functions pertaining to memory. Persons displaying lesions in the anterior thalamus, preventing input from the pathway involving the hippocampus, mammillary bodies and the MTT, display forms of amnesia, supporting the anterior thalamus's involvement in episodic memory. However, although the hypothalamus projects to both the mammillary bodies and the anterior nuclei of the thalamus, the anterior nuclei receive input from hippocampal cells deep to the pyramidal c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulvinar Nuclei
The pulvinar nuclei or nuclei of the pulvinar (nuclei pulvinares) are the nuclei ( cell bodies of neurons) located in the thalamus (a part of the vertebrate brain). As a group they make up the collection called the pulvinar of the thalamus (pulvinar thalami), usually just called the pulvinar. The pulvinar is usually grouped as one of the ''lateral thalamic nuclei'' in rodents and carnivores, and stands as an independent complex in primates. Pulvinar acts as an association nucleus that, along with medial dorsal nucleus, connected with parietal, occipital, and temporal lobes, but the function is largely unknown. No distinctive syndrome or obvious sensory deficit can be linked to either one. Structure By convention, the pulvinar is divided into four nuclei: Their connectomic details are as follows: * The ''lateral'' and ''inferior'' pulvinar nuclei have widespread connections with early visual cortical areas. * The dorsal part of the ''lateral'' pulvinar nucleus predominant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
