Mergeto subthalamus date December 2009 Unreferenced date December 2009 The prethalamus formerly described as ventral thalamus or subthalamus is part of the diencephalon and therefore part of the brain . Developmental biologists prefer the term prethalamus, as it can be genetically defined Puelles and Rubenstein, 2003 , whereas human anatomists often use the expression subthalamus. The prethalamus is part of the mid diencephalic territory MDT containing also the zona limitans intrathalamica ZLI , and the thalamus . Caudally, the prethalamus is separated from the thalamus by the ZLI acting as lineage restriction boundary. The pro neural gene Dlx gene Dlx2 serves a typical marker of the prethalamus. Typical nucleus neuroanatomy nuclei of the prethalamus are the zona incerta , thalamic reticular nucleus , and the fields of Forel . The prethalamus is patterned by Sonic hedgehog signalling from the ZLI. Anatomically, it develops efferent nerve efferent output connections to the striatum caudate nucleus and putamen in the telencephalon , to the thalamus medial and lateral nuclear groups in the diencephalon, and to the red nucleus and substantia nigra in the mesencephalon . It receives afferent nerve afferent input connections from the substantia nigra and striatum. Diencephalon Category Diencephalon ... more details
Fields of Forel is an area in a deep part of the brain known as the diencephalon . It is below the thalamus and consists of three defined, white matter areas of the subthalamus . These three regions are named H fields for Haubenfelder . The first, field H1, is the thalamic fasciculus , a horizontal white matter tract between the subthalamus and the thalamus. These fibers are projections to the thalamus from the basal ganglia globus pallidus and the cerebellum . H1 is separated from H2 by the zona incerta . Field H2 sometimes synonymous with lenticular fasciculus is also made up of projections from the pallidum to the thalamus, but these course the subthalamic nucleus dorsal . Field H3 aka the prerubral field , is a large zone of mixed gray and white matter located just rostral In front of the red nucleus. External links 1. http www.biology online.org dictionary Fields of forel 2. Forel, A. 1877 . Untersuchungen ber die Haubenregion und ihre oberen Verkn pfungen im Gehirne des Menschen und einiger S ugethiere, mit Beitr gen zu den Methoden der Gehirnuntersuchung . Archiv f r Psychiatrie und Nervenkrankheiten 7 393 495. doi 10.1007 BF02041873. Category Nervous system neuroscience stub Diencephalon Category Neuroanatomy Category Brainstem Category Cerebrum Category Central nervous system ... more details
Infobox Brain Name Ansa lenticularis Latin GraySubject 189 GrayPage 837 Image DA loops in PD.jpg Caption The image shows dopaminergic pathways of the human brain in normal condition left and Parkinsons Disease right . Red Arrows indicate suppression of the target, blue arrows indicate stimulation of target structure. Ansa lenticularis visible but not labeled, as red line from GPi to THA. Image2 Caption2 System Precursor BrainInfoType hier BrainInfoNumber 427 MeshName MeshNumber DorlandsPre a 44 DorlandsSuf 12138610 The ansa lenticularis ansa lentiformis in older texts is a part of the brain, making up the superior layer of the Substantia innominata substantia innominata of Meynert . Its fibers, derived from the medullary lamina of the lentiform nucleus , pass medially to end in the thalamus and subthalamic region, while others are said to end in the tegmentum and red nucleus . It is classified by NeuroNames as part of the subthalamus . External links LoyolaMedEd Neuro nlDEs nl04s.html Gray s Diencephalon Rostral basal ganglia and associated structures Neural tracts Category Neuroanatomy ... more details
Infobox Brain Name Medullary laminae of thalamus Latin lamina medullaris lateralis thalami, lamina medullaris medialis thalami GraySubject GrayPage Image Constudthal.gif Caption Thalamic nuclei Image2 Caption2 Precursor System Artery Vein Nerve Lymph MeshName MeshNumber Medullary laminae of thalamus are layers of myelin ated fibres that appear on cross sections of the thalamus . They also are commonly referred to as laminae medullares thalami or medullary layers of thalamus . The specific layers are ref cite web url http www.medilexicon.com medicaldictionary.php?s medullary laminae of thalamus title Medilexicon Medullary laminae of thalamus ref Lamina medullaris lateralis external medullary lamina ref BrainInfo hier 350 ref separates ventral and Human anatomical terms Anatomical directions lateral thalamus from the subthalamus and thalamic reticular nucleus Lamina medullaris medialis internal medullary lamina ref BrainInfo hier 351 ref positioned between the dorsomedial and ventral nuclei of thalamus, encloses the intralaminar nuclei centromedian nucleus , paracentral, and central lateral References reflist Diencephalon Category Cerebellum anatomy stub ... more details
Infobox Brain Name Prosencephalon forebrain Latin GraySubject 189 GrayPage 741 Image EmbryonicBrain.svg Caption Diagram depicting the main subdivisions of the embryonic vertebrate brain. These regions will later differentiate into forebrain, midbrain and hindbrain structures. Image2 Caption2 IsPartOf Components Artery Vein BrainInfoType BrainInfoNumber MeshName MeshNumber NeuroLex Forebrain NeuroLexID birnlex 1509 In the anatomy of the brain of vertebrates , the prosencephalon or forebrain is the Anatomical terms of location Directional terms rostral most forward most portion of the brain . The prosencephalon, the mesencephalon midbrain , and rhombencephalon hindbrain are the three primary portions of the brain during early developmental biology development of the central nervous system . It controls body temperature, reproductive functions, eating, sleeping, and any display of emotions. At the five vesicle stage, the prosencephalon separates into the diencephalon prethalamus , thalamus , hypothalamus , subthalamus , epithalamus , and pretectum and the telencephalon cerebrum . The cerebrum consists of the cerebral cortex , underlying white matter , and the basal ganglia . When the embryonic prosencephalon fails to divide the brain into two lobes, it results in a condition known as holoprosencephaly . Additional images gallery Image Gray40.png Embryo between eighteen and twenty one days. Image Gray460.png Head of chick embryo of about thirty eight hours incubation, viewed from the ventral surface. X 26 gallery See also List of regions in the human brain External links http www.neuinfo.org nif nifgwt.html?query 22Forebrain 22 NIF Search Forebrain via the Neuroscience Information Framework Nervous system Diencephalon Forebrain Category Cerebrum Category Developmental biology neuroanatomy stub ca Prosenc fal cs P edn mozek de Prosencephalon es Prosenc falo fr Prosenc phale ko hy it Prosencefalo kk nl Prosencephalon no Prosencephalon pl Przo ... more details
Infobox Brain Name PAGENAME Latin fasciculus thalamicus GraySubject GrayPage Image DA loops in PD.jpg Caption The image shows dopaminergic pathways of the human brain in normal condition left and Parkinsons Disease right . Red Arrows indicate suppression of the target, blue arrows indicate stimulation of target structure. Thalamic fasciculus visible but not labeled, as red line from GPi to THA. Image2 Caption2 IsPartOf Components Artery Vein BrainInfoType hier BrainInfoNumber 422 MeshName MeshNumber DorlandsPre f 03 DorlandsSuf 12356375 The thalamic fasciculus is a component of the subthalamus . It is sometimes considered synonymous with field H1 of Forel . Nerve fibres forming a composite bundle containing cerebellothalamic crossed and pallidothalamic uncrossed fibres that is insinuated between the thalamus and zona incerta . The thalamic fasciculus consists of the joint fibers of the ansa lenticularis and the lenticular fasciculus , coming from different portions of the medial globus pallidus , before they jointly enter the ventral lateral nucleus of the thalamus . ref name isbn1 4160 3445 5 cite book author Estomih Mtui Gregory Gruener title Clinical Neuroanatomy and Neuroscience With STUDENT CONSULT Online Access publisher Saunders location Philadelphia year 2006 pages 359 isbn 1 4160 3445 5 oclc doi accessdate ref References reflist External links http www.meddean.luc.edu lumen MedEd Neuro frames nlDEs nl06fr.htm http www.endotext.org neuroendo neuroendo3b neuroendo3b 2.htm see figure 12 http isc.temple.edu neuroanatomy lab atlas mdbg Diencephalon Rostral basal ganglia and associated structures Neural tracts Category Diencephalon Neuroscience stub ... more details
Infobox Brain Name PAGENAME Latin diencephalon GraySubject 189 GrayPage 807 Image EmbryonicBrain.svg Caption Diagram depicting the main subdivisions of the embryonic vertebrate brain. These regions will later differentiate into forebrain, midbrain and hindbrain structures. Image2 Gray645.png Caption2 Reconstruction of peripheral nerves of a human embryo of 10.2 mm. Label for Diencephalon is at left. IsPartOf Components Artery Vein BrainInfoType hier BrainInfoNumber 271 MeshName Diencephalon MeshNumber A08.186.211.730.385 NeuroLex Diencephalon NeuroLexID birnlex 1503 Code TerminologiaHistologica 3 11 03.5.00001 The diencephalon interbrain is the region of the vertebrate neural tube which gives rise to posterior forebrain structures. In Prenatal development development , the forebrain develops from the prosencephalon , the most anterior vesicle of the neural tube which later forms both the diencephalon and the telencephalon . In adults, the Diencephalon appears at the upper end of the brain stem, situated between the cerebrum and the brain stem. It is made up of four distinct components the thalamus , the subthalamus , the hypothalamus and the epithalamus . ref cite book last Jacobson & Marcus title Neuroanatomy for the Neuroscientist year 2008 publisher Springer isbn 9780387709703 pages 147 ref Organization diencephalon mid diencephalic territory prethalamus zona limitans intrathalamica thalamus hypothalamus epithalamus pretectum pineal gland Roles The diencephalon is the region of the embryonic vertebrate neural tube that gives rise to posterior forebrain structures including the thalamus , hypothalamus , Posterior anatomy posterior portion of the pituitary gland , and pineal gland . The hypothalamus performs numerous vital functions, most of which relate directly or indirectly to the regulation of visceral activities by way of other brain regions and the autonomic nervous system . File Parahippocampal gyrus.jpg thumb right 300px Diencephalon Three dimensional repre ... more details
Refimprove date December 2008 Infobox Brain Name Globus pallidus Latin GraySubject GrayPage Image Brain structure.gif Caption Globus pallidus labeled at bottom right. Image2 DA loops in PD.jpg Caption2 DA loops in PD IsPartOf Components Artery Vein BrainInfoType hier BrainInfoNumber 213 MeshName Globus Pallidus MeshNumber A08.186.211.730.885.105.487.397 NeuroLex Globus pallidus NeuroLexID birnlex 1234 DorlandsPre g 07 DorlandsSuf 12394364 The globus pallidus Latin for pale globe also known as paleostriatum , is a sub Cerebral cortex cortical structure of the brain . Topographically, it is part of the telencephalon , but retains close functional ties with the subthalamus both of which are part of the extrapyramidal motor system . ref cite book url http books.google.si books?id wlGDPwz 7KoC&lpg PA211&ots UDAn MHYjU&dq 2Bsubthalamus 20part 20 22globus 20pallidus 22&pg PA211 v onepage&q subthalamus 20part 20 22globus 20pallidus 22&f false title Theme atlas of anatomy head and neuroanathomy ref The globus pallidus is a major component of the basal ganglia core along with the striatum and its direct target, the substantia nigra . The latter are made up of similar neuronal elements, have similar afferents from the dorsal striatum and have a similar synapse synaptology neither receive cortical afferents. History of name The origin of the name is not established. It was known by Dejerine 1906 but not by Santiago Ram n y Cajal 1909 1911 . As the elements in no way have the shape of a globe, Foix and Nicolesco 1925 , the Vogts 1941 , Crosby et al. 1962 followed by the Terminologia anatomica proposed the simpler term neuter adjective of pallidum pale . For a long time the globus pallidus was linked to the putamen and termed the lentiform nucleus nucleus lenticularis or lentiformis , a heterogeneous anatomical entity that is part of the striatum rather than the pallidum. The link with the substantia nigra pars reticulata was stressed very early on due to the similarities in dend ... more details
other uses Infobox Anatomy Name Grey matter Latin substantia grisea GraySubject GrayPage Image spinal nerve.svg Caption The formation of the spinal nerve from the dorsal and ventral roots. Gray matter labeled at center right. Image2 Grey matter and white matter very high mag.jpg Caption2 Micrograph showing grey matter, with the characteristic neuron neuronal cell bodies right of image dark shade of pink , and white matter with its characteristic fine meshwork like appearance left of image lighter shade of pink . HPS stain . System MeshName MeshNumber Dorlands nine 100008780 DorlandsID Gray matter Code Terminologia Anatomica TA A14.1.00.002 Grey matter or gray matter is a major component of the central nervous system , consisting of neuron al Soma biology cell bodies , neuropil dendrites and myelin unmyelinated axons , glial cell s astroglia and oligodendrocytes and Capillary capillaries . Grey matter contains neural cell bodies, in contrast to white matter , which does not and mostly contains myelinated axon tracts. ref name Purves cite book author Purves, Dale, George J. Augustine, David Fitzpatrick, William C. Hall, Anthony Samuel LaMantia, James O. McNamara, and Leonard E. White title Neuroscience. 4th ed. publisher Sinauer Associates pages 15 16 year 2008 isbn 978 0 87893 697 7 ref The color difference arises mainly from the whiteness of myelin. In living tissue, grey matter actually has a grey brown color, which comes from capillary blood vessels and neuronal cell bodies. Function Grey matter is made up of neuronal cell bodies. The grey matter includes regions of the brain involved in muscle control, sensory perception such as seeing and hearing, memory, emotions, and speech. Distribution Grey matter is distributed at the surface of the cerebral hemisphere s cerebral cortex and of the cerebellum cerebellar cortex , as well as in the depths of the cerebrum thalamus hypothalamus subthalamus , basal ganglia putamen , globus pallidus , nucleus accumbens septal nucl ... more details
, and subthalamic nucleus or subthalamus . This latter, glutamatergic nucleus is reciprocally connected ... rem sleep in humans a deep brain polysomnographic study. SLEEP 32 9 1117 26. ref This suggests that the subthalamus ... more details
Infobox Brain Name Subthalamic nucleus Latin nucleus subthalamicus GraySubject GrayPage Image Basal ganglia coronal sections large.png Caption Coronal slices of human brain showing the basal ganglia , subthalamic nucleus STN and substantia nigra SN . Image2 DA loops in PD.svg Caption2 DA loops in Parkinson s disease IsPartOf Basal ganglia Components Artery Vein BrainInfoType hier BrainInfoNumber 418 MeshName Subthalamic Nucleus MeshNumber A08.186.211.730.385.800.800 DorlandsPre n 11 DorlandsSuf 14166739 The subthalamic nucleus is a small lens shaped Nucleus neuroanatomy nucleus in the brain where it is, from a functional point of view, part of the basal ganglia system. Anatomically, it is the major part of subthalamus . As suggested by its name, the subthalamic nucleus is located Anatomical terms of location ventral to the thalamus . It is also dorsal to the substantia nigra and medial to the internal capsule . It was first described by Jules Bernard Luys in 1865, ref cite book last Luys first Jules Bernard authorlink Jules Bernard Luys year 1865 title Recherches sur le syst me c r bro spinal, sa structure, ses fonctions et ses maladies publisher Bailli re location Paris language French ref and the term corpus Luysi or Luys body is still sometimes used. Anatomy Structure The principal type of neuron found in the subthalamic nucleus has rather long sparsely spiny dendrite s. ref name Afsharpour1985 Cite doi 10.1002 cne.902360102 ref ref Cite doi 10.1002 cne.901680105 ref The dendritic arborizations are ellipsoid, replicating in smaller dimension the shape of the nucleus. ref cite journal author Yelnik, J. & Percheron, G. title Subthalamic neurons in primates a quantitative and comparative anatomy journal Neuroscience year 1979 pages 1717 1743 volume 4 issue 11 pmid 117397 doi 10.1016 0306 4522 79 90030 7 ref The dimensions of these arborizations 1200,600 and 300 m are similar across many species including rat, cat, monkey and man which is unusual. However, the numbe ... more details
Infobox Brain Name Zona incerta Latin GraySubject 189 GrayPage 812 Image Caption Image2 Caption2 IsPartOf Components Artery Vein BrainInfoType hier BrainInfoNumber 421 MeshName MeshNumber DorlandsPre z 01 DorlandsSuf 12869746 The zona incerta is a horizontally elongated region of gray matter cells in the subthalamus below the thalamus . Its connections project extensively over the brain from the cerebral cortex down into the spinal cord . Its function is unknown though several have been proposed related to limbic motor integration such as controlling visceral activity and pain gating sensory input and synchronizing cortical and subcortical brain rhythms. Its dysfunction may play a role in central pain syndrome . It is also been identified as a promising deep brain stimulation therapy target for treating Parkinsons Disease . Its existence was first described by Auguste Forel in 1877 as a region of which nothing certain can be said . ref Cite doi 10.1007 BF02041873 noedit ref ref name Mitrofanis05 Cite doi 10.1016 j.neuroscience.2004.08.017 noedit ref A hundred and thirty years later in 2007, Nadia Urbain and Martin Desch nes of Universit Laval noted that the zona incerta is among the least studied regions of the brain its name does not even appear in the index of many textbooks. ref name Urbain Cite doi 10.1016 j.neuron.2007.10.023 noedit ref Anatomy This nucleus neuroanatomy nucleus is located Anatomical terms of location medially to the internal capsule , ventral to the thalamus , and is contiguous with the thalamic reticular nucleus . The nucleus separates the lenticular fasciculus from the thalamic fasciculus also known as the field H1 of Forel . Its cells are very heterogeneous differing widely in their shape and size. Its chemoarchitecture is also diverse containing up to 20 different types of neurochemically defined cells. It has been noted that There are few diencephalic regions that have as much cellular and neurochemical diversity . ref name Mitrofanis05 I ... more details
Infobox Brain Name Reticular activating system Latin GraySubject GrayPage Image Gray690.png Caption Deep dissection of brain stem . Ventral view. Reticular formation labeled near center. Image2 Caption2 IsPartOf Components Artery Vein BrainInfoType ancil BrainInfoNumber 231 MeshName MeshNumber DorlandsPre s 33 DorlandsSuf 12787787 The reticular activating system RAS is an area of the brain including the reticular formation and its connections responsible for regulating arousal and Sleep wake cycle sleep wake transitions . History and Etymology Moruzzi and Magoun first investigated the neural components regulating the brain s sleep wake mechanisms in 1949. Physiologists had proposed that some structure deep within the brain controlled mental wakefulness and alertness. ref name Steriade1996 cite journal doi 10.1126 science.272.5259.225 author Steriade, M. title Arousal Revisiting the reticular activating system journal Science volume 272 issue 5259 pages 225 226 year 1996 pmid 8602506 ref It used to be thought that wakefulness depended only on the direct reception of Afferent nerve fiber afferent sensory stimuli at the cerebral cortex . The direct electrical stimulation of the brain could simulate electrocortical relays, so Magoun used this to demonstrate, on two separate areas of a brainstem of a cat, how to produce wakefulness from sleep. First the ascending Somatic nervous system somatic and auditory paths second, a series of ascending relays from the reticular formation of the lower brain stem through the Mesencephalon mesencephalic tegmentum , subthalamus and hypothalamus to the internal capsule . ref name Magoun The latter was of particular interest, as this series of relays did not correspond to any known anatomical pathways for the wakefullness signal transduction and was coined the ascending reticular activating system RAS . Next, the significance of this newly identified relay system was evaluated by placing lesions in the Anatomical terms of location medial ... more details
Encyclopedia
top
