The basal ganglia (or basal nuclei) are a group of nuclei in the brain interconnected with the cerebral cortex, thalamus and brainstem. Mammalian basal ganglia are associated with a variety of functions: motor control, cognition, emotions and learning. Image File history File links Brain_structure. ... For other uses, see Latin (disambiguation). ... NeuroNames is a system of nomenclature for the brain and related structures. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... Elseviers logo. ... In neuroanatomy, a nucleus is a central nervous system structure that is composed mainly of gray matter, and which acts as a hub or transit point for electrical signals in a single neural subsystem. ... The human brain In animals, the brain (enkephalos) (Greek for in the skull), is the control center of the central nervous system, responsible for behavior. ... For other uses, see Cortex. ... The thalamus (from Greek θάλαμος = bedroom, chamber, IPA= /ˈθæləməs/) is a pair and symmetric part of the brain. ... The brain stem is the stalk of the brain below the cerebral hemispheres. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria Mammals (class Mammalia) are warm-blooded, vertebrate animals characterized by the presence of sweat glands, including those that produce milk, and by the presence of: hair, three middle ear bones used in hearing, and a neocortex... Learning is the acquisition and development of memories and behaviors, including skills, knowledge, understanding, values, and wisdom. ...

Terminology

As it refers to a group of nuclei, the term "basal ganglia" is plural (the singular of ganglia is ganglion). However this is a misnomer, as "ganglion" refers to a somatic cluster within the peripheral nervous system, whereas the basal ganglia are within the central nervous system (CNS). A somatic cluster within the CNS is referred to as a nucleus, so some neuroanatomists refer to the basal ganglia as the "basal nuclei".^[1] This is a dorsal root ganglion (DRG) from a chicken embryo (around stage of day 7) after incubation overnight in NGF growth medium stained with anti-neurofilament antibody. ... This article does not cite any references or sources. ... The soma, or perikaryon, is the bulbous end of a neuron, containing the cell nucleus. ... The Peripheral nervous system resides or extends outside the CNS central nervous system (the brain and spinal cord) to serve the limbs and organs. ... A diagram showing the CNS: 1. ... Neuroanatomy is the anatomy of the nervous system. ...

History

The acceptance that the basal ganglia system constitutes one major cerebral system has been slow to appear.

The first anatomical identification of distinct subcortical structures was published by Thomas Willis in 1664.^[2] For many years, the term corpus striatum was used to describe a large group of subcortical elements, some of which were later discovered to be functionally unrelated. Additionally, the putamen and the caudate nucleus were not linked together. The putamen was thought to be associated to the pallidum in what used to be called the "nucleus lenticularis" (see lentiform nucleus on the fig.). Human heart and lungs, from an older edition of Grays Anatomy. ... Thomas Willis Thomas Willis (1621-1673) was an English physician who played an important part in the history of the science of anatomy and was a co-founder of the Royal Society (1662). ... Events March 12 - New Jersey becomes a colony of England. ... Coronal slices of human brain showing the basal ganglia, the striatum and pallidum globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... The putamen is a structure in the middle of the brain, forming the striatum together with the caudate nucleus. ... Grays Fig. ... Coronal slices of human brain showing the basal ganglia, globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... The lentiform nucleus or lenticular nucleus describes the putamen and the globus pallidus within the basal ganglia. ...

Pioneering work by Cécile and Oskar Vogt (1941) greatly simplified the description of the basal ganglia by proposing the term striatum to describe the group of structures consisting of the caudate nucleus, the putamen and the mass linking them ventrally, the nucleus accumbens. Coronal slices of human brain showing the basal ganglia, the striatum and pallidum globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. ... The nucleus accumbens (NAcc), also known as the accumbens nucleus or as the nucleus accumbens septi (Latin for nucleus leaning against the septum), is a collection of neurons located where the head of the caudate and the anterior portion of the putamen meet just lateral to the septum pellucidum. ...

The striatum gets its name from the striated appearance created by radiating dense bundles of striato-pallido-nigral axons, described by anatomist Kinnear Wilson as "pencil-like". The anatomical link of the striatum with its primary targets, the pallidum and the substantia nigra was later discovered. Together, these structures constitute the striato-pallido-nigral bundle, which is the core of the basal ganglia. This nerve bundle forms the so-called "comb bundle of Edinger" when it crosses the internal capsule. An axon, or nerve fiber, is a long slender projection of a nerve cell, or neuron, which conducts electrical impulses away from the neurons cell body or soma. ... Coronal slices of human brain showing the basal ganglia, globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... The substantia nigra, (Latin for black substance, Soemering) or locus niger is a heterogeneous portion of the midbrain, separating the pes (foot) from the tegmentum (covering), and a major element of the basal ganglia system. ... The internal capsule is an area of white matter in the brain that separates the caudate nucleus and the thalamus from the lenticular nucleus. ...

Additional structures that later became associated with the basal ganglia are the "body of Luys" (1865) (nucleus of Luys on the figure) or subthalamic nucleus, whose lesion was known to produce movement disorders. More recently, other areas such as the central complex (centre médian-parafascicular) and the pedunculopontine complex have been thought to be regulators of the basal ganglia. Coronal slices of human brain showing the basal ganglia, globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... The pedunculopontine nucleus (PPN) (or pedunculopontine tegmental nucleus, PPTN) is located in the brainstem, caudal to the substantia nigra and adjacent to the superior cerebellar peduncle. ...

At the beginning of the 20th century, the basal ganglia system was associated with motor functions, as lesions of these areas would often result in disordered movement in humans (chorea, athetosis, Parkinson's disease). Chorea may refer to: Chorea, an ancient Greek round dance accompanied by singing. ... Athetosis is a continuous stream of slow, sinuous, writhing movements, typically of the hands and feet. ...

Anatomical subdivisions

Coronal slices of human brain showing the basal ganglia.
ROSTRAL: striatum, globus pallidus (GPe and GPi)
CAUDAL: subthalamic nucleus (STN), substantia nigra (SN)

Main article: Anatomical subdivisions and connections of the basal ganglia

The five individual nuclei that make up the primate basal ganglia, along with their major subdivisions, are: Image File history File links Basal-ganglia-coronal-sections-large. ... Image File history File links Basal-ganglia-coronal-sections-large. ... In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. ... Coronal slices of human brain showing the basal ganglia, the striatum and pallidum globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... The globus pallidus (Latin for pale body) is a sub-cortical structure in the brain. ... Coronal slices of human brain showing the basal ganglia, globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... The substantia nigra, (Latin for black substance, Soemering) or locus niger is a heterogeneous portion of the midbrain, separating the pes (foot) from the tegmentum (covering), and a major element of the basal ganglia system. ... The basal ganglia system is a major cerebral system that has only recently been recognized. ... Families 15, See classification A primate is any member of the biological order Primates, the group that contains all the species commonly related to the lemurs, monkeys, and apes, with the latter category including humans. ...

rostral In zootomy, several terms are used to describe the location of organs and other structures in the body of bilateral animals. ...

• the striatum, which consists of
  • putamen
  • caudate nucleus
  • nucleus accumbens
• external segment of the globus pallidus (GPe)
• internal segment of the globus pallidus (GPi)

caudal Coronal slices of human brain showing the basal ganglia, the striatum and pallidum globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... The putamen is a structure in the middle of the brain, forming the striatum together with the caudate nucleus. ... Grays Fig. ... The nucleus accumbens (NAcc), also known as the accumbens nucleus or as the nucleus accumbens septi (Latin for nucleus leaning against the septum), is a collection of neurons located where the head of the caudate and the anterior portion of the putamen meet just lateral to the septum pellucidum. ... The globus pallidus (Latin for pale body) is a sub-cortical structure in the brain. ... In zootomy, several terms are used to describe the location of organs and other structures in the body of bilateral animals. ...

• subthalamic nucleus (STN)
• substantia nigra (SN)
  • substantia nigra pars compacta (SNc)
  • substantia nigra pars reticulata (SNr)
  • substantia nigra pars lateralis (SNl)

There are 2 sets of basal ganglia in the mammalian brain, mirrored in the left and right hemispheres. Coronal slices of human brain showing the basal ganglia, globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... The substantia nigra, (Latin for black substance, Soemering) or locus niger is a heterogeneous portion of the midbrain, separating the pes (foot) from the tegmentum (covering), and a major element of the basal ganglia system. ...

Two coronal sections are used to show the basal ganglia; the STN and substantia nigra lie deeper back in the brain (more caudal). Images show two schematic coronal cross-sections of the human brain with nuclei of the basal ganglia labeled on the right side. In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. ... In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. ... This article is about modern humans. ...

Functionally, the basal ganglia consist of a series of circuits, such as skeletomotor, limbic and occulomotor circuits. Each circuit projects to specific nuclei within the basal ganglia and its projections e.g. the skeletomotor circuit projects to the ventral lateral, lateral ventral anterior and centromedian thalamic nuclei.

Comparative anatomy and naming

"Basal ganglia"-like areas are found in the central nervous systems of many species. The striatal and pallidal components can be clearly identified in all amniotes (mammals, birds, and reptiles) and amphibians. The anatomical connections of these nuclei and their pharmacology also appear relatively conserved. Non-tetrapod vertebrates such as fish also display basal ganglia-like structures, although the data are less clear in this case. Living subgroups Class Synapsida    Class Mammalia (mammals) Class Sauropsida    Anapsida        Testudines (turtles)    Diapsida        Lepidosauria           Squamata (lizards & snakes)           Sphenodontida (tuatara)        Archosauria           Crocodilia (crocodiles)           Class Aves (birds) The amniotes are a taxon of tetrapod vertebrates that include the Synapsida (mammals) and Sauropsida (reptiles and dinosaurs, including birds). ... For other uses, see Amphibian (disambiguation). ... Pharmacology (in Greek: pharmakon (φάρμακον) meaning drug, and lego (λέγω) to tell (about)) is the study of how drugs interact with living organisms to produce a change in function. ... Groups See text. ...

The names given to the various nuclei of the basal ganglia are different in different species:

• For example, the "internal segment of the globus pallidus" in primates is called the "entopenduncular nucleus" in rodents.
• The "striatum" and "external segment of the globus pallidus" in primates are called the "paleostriatum augmentatum" and "paleostriatum primitivum" respectively in birds.

A clear emergent issue in comparative anatomy of the basal ganglia is the development of this system through phylogeny as a convergent cortically re-entrant loop in conjunction with the development and expansion of the cortical mantle. There is controversy, however, regarding the extent to which convergent selective processing occurs versus segregated parallel processing within re-entrant closed loops of the basal ganglia. Regardless, the transformation of the basal ganglia into a cortically re-entrant system in mammalian evolution occurs through a re-direction of pallidal (or "paleostriatum primitivum") output from midbrain targets such as the superior colliculus, as occurs in sauropsid brain, to specific regions of the ventral thalamus and from there back to specified regions of the cerebral cortex that form a subset of those cortical regions projecting into the striatum. The abrupt rostral re-direction of the pathway from the internal segment of the globus pallidus into the ventral thalamus--via the path of the ansa lenticularis--could be viewed as a footprint of this evolutionary transformation of basal ganglia outflow and targeted influence. The evolutionary emergence of cortical re-entrant systems in the brain has been postulated by Gerald Edelman as a critical basis for the emergence of primary consciousness in the theory of Neural Darwinism.^{[citation needed]} Suborders Sciuromorpha Castorimorpha Myomorpha Anomaluromorpha Hystricomorpha Rodentia is an order of mammals also known as rodents, characterised by two continuously-growing incisors in the upper and lower jaws which must be kept short by gnawing. ... Clades Subclass Anapsida Subclass Diapsida Infraclass Lepidosauromorpha Infraclass Archosauromorpha Sauropsids are a diverse group of mostly egg-laying vertebrate animals. ... The superior layer of the substantia innominata of Meynert is named the ansa lenticularis (ansa lentiformis in older texts), and 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... Gerald Maurice Edelman (born July 1, 1929) is a biologist who won the Nobel Prize in Physiology or Medicine in 1972 for his work on the immune system. ... Consciousness is a quality of the mind generally regarded to comprise qualities such as subjectivity, self-awareness, sentience, sapience, and the ability to perceive the relationship between oneself and ones environment. ... The term Neural Darwinism is used in two different ways. ...

Connections

Connectivity Diagram showing glutamatergic pathways as red, dopaminergic as magenta and GABA pathways as blue.

Basal ganglia connectivity is illustrated in the figure. Classic connectivity diagram of the Basal Ganglia Created by Andrew Gillies File links The following pages link to this file: Basal ganglia Wikipedia:Help desk/Archive 16 Categories: GFDL images ... Classic connectivity diagram of the Basal Ganglia Created by Andrew Gillies File links The following pages link to this file: Basal ganglia Wikipedia:Help desk/Archive 16 Categories: GFDL images ... Glutamic acid or glutamate (the anionic form of glutamic acid) is one of the 20 most common natural amino acids. ... Dopaminergic means related to the neurotransmitter dopamine. A synapse is dopaminergic if it uses dopamine as its neurotransmitter. ... Gaba may refer to: Gabâ or gabaa (Philippines), the concept of negative karma of the Cebuano people GABA, the gamma-amino-butyric acid neurotransmitter GABA receptor, in biology, receptors with GABA as their endogenous ligand Gaba 1 to 1, an English conversational school in Japan Marianne Gaba, a US model...

The striatum is the main (but not the only) input zone for other brain areas to connect to the basal ganglia. Via the striatum, the basal ganglia receives input from the cortex, mainly from the motor and prefrontal cortices. For other uses, see Cortex. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... “Prefrontal” redirects here. ...

The circuitry of the basal ganglia is often divided into two major pathways, the direct pathway and the indirect pathway: // Traditionally, the term neural network had been used to refer to a network or circuitry of biological neurons. ...

Dopamine from the substantia nigra pars compacta stimulates all of the dopamine receptors, but because the different pathways express different receptors, and the different receptors have different effects, dopamine serves to activate the direct pathway over the indirect pathway, and thus increase the signal to the thalamus. The dopamine receptors are a class of metabotropic G-protein-coupled receptors with the neurotransmitter dopamine as their endogenous ligand. ... The substantia nigra, (Latin for black substance, Soemering) or locus niger is a heterogeneous portion of the midbrain, separating the pes (foot) from the tegmentum (covering), and a major element of the basal ganglia system. ... The dopamine receptors are a class of metabotropic G-protein-coupled receptors with the neurotransmitter dopamine as their endogenous ligand. ...

Neurotransmitters

The different types of neuron of the basal ganglia biosynthesize different neurotransmitters. Chemical structure of D-aspartic acid, a common amino acid neurotransmitter. ...

Gaba may refer to: Gabâ or gabaa (Philippines), the concept of negative karma of the Cebuano people GABA, the gamma-amino-butyric acid neurotransmitter GABA receptor, in biology, receptors with GABA as their endogenous ligand Gaba 1 to 1, an English conversational school in Japan Marianne Gaba, a US model... For other uses, see Dopamine (disambiguation). ... For other uses, see Dopamine (disambiguation). ... Tourette syndrome — also called Tourettes syndrome, Tourette Spectrum (TS), Tourettes disorder, or Gilles de la Tourette syndrome (after its discoverer, Georges Gilles de la Tourette) — is a neurological or neurochemical disorder characterized by tics — involuntary, rapid, sudden movements or vocalizations that occur repeatedly in the... Glutamate is the anion of glutamic acid. ... Hemiballismus is a movement disorder characterised by unilateral wild, large amplitude flinging movements of the arm and leg, normally causing falls and preventing postural maintenance. ...

Other disorders linked with the basal ganglia

• Attention-deficit hyperactivity disorder (ADHD)
• Athymhormic syndrome (PAP syndrome)
• Cerebral palsy: basal ganglia damage during second and third trimester of pregnancy
• Dystonia
• Fahr's disease
• Foreign accent syndrome (FAS)
• Lesch-Nyhan syndrome
• Obsessive-compulsive disorder
• Parkinson's disease
• Tourette's disorder
• Tardive dyskinesia, caused by chronic antipsychotic treatment
• Stuttering^[3]
• Spasmodic dysphonia
• Wilson's disease

Attention-Deficit/Hyperactivity Disorder (ADHD) previously known as Attention Deficit Disorder (ADD), is generally considered to be a developmental disorder, largely neurological in nature, affecting about 5% of the worlds population. ... Athymhormic syndrome, or psychic akinesia, is a rare neurological syndrome characterized by extreme passivity, apathy, and a profound generalized loss of self-motivation. ... Athymhormic syndrome, or psychic akinesia, is a rare neurological syndrome characterized by extreme passivity, apathy, and a profound generalized loss of self-motivation. ... This article or section is in need of attention from an expert on the subject. ... Dystonia (literally, abnormal muscle tone) is a generic term used to describe a neurological movement disorder involving involuntary, sustained muscle contractions. ... It has been suggested that this article or section be merged with Fahrs syndrome. ... Foreign accent syndrome is a rare medical condition that usually follows a severe brain injury, such as a stroke or a head injury. ... -1... “Tourette” redirects here. ... Tardive dyskinesia is a serious neurological disorder caused by the long-term and/or high-dose use of dopamine antagonists, usually antipsychotics and among them especially the typical antipsychotics. ... The term antipsychotic is applied to a group of drugs used to treat psychosis. ... “Stutter” redirects here. ... Spasmodic dysphonia (or laryngeal dystonia) is a voice disorder characterized by involuntary movements of one or more muscles of the larynx (vocal folds or voice box) during speech. ... Wilsons disease or hepatolenticular degeneration is an autosomal recessive hereditary disease, with an incidence of about 1 in 30,000 in most parts of the world and a male preponderance. ...

See also

• Anatomical subdivisions and connections of the basal ganglia
• Primate basal ganglia system

The basal ganglia system is a major cerebral system that has only recently been recognized. ... The basal ganglia system is a pair and symmetrical major cerebral system that has only recently been recognized. ...

References

1. ^ Soltanzadeh, Akbar (2004). Neurologic Disorers. Tehran: Jafari. ISBN ISBN 964-6088-03-1. 
2. ^ Andrew Gilies, A brief history of the basal ganglia, retrieved on 27 June 2005
3. ^ Alm PA (2004). "Stuttering and the basal ganglia circuits: a critical review of possible relations". Journal of communication disorders 37 (4): 325-69. PMID 15159193. 

• Nolte, John, The Human Brain: An Introduction to its Functional Anatomy (Fifth Edition). (St. Louis: Mosby, Inc., 2002), 464-484. ISBN 0-323-01320-1
• Parent, André, Comparative Neurobiology of the Basal Ganglia (Wiley, New York, 1986), ISBN 0-471-80348-0
• Reynolds JN, Hyland BI, Wickens JR (2001). "A cellular mechanism of reward-related learning". Nature 413 (6851): 67-70. PMID 11544526. 

is the 178th day of the year (179th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... Nature is a prominent scientific journal, first published on 4 November 1869. ...

Additional images

Basal ganglia Image File history File links Size of this preview: 800 × 399 pixelsFull resolution (2026 × 1010 pixel, file size: 449 KB, MIME type: image/jpeg) Anatomie der Basalganglien (schematisiert) 4 halbschematische Koronarschnitte File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old...

The major components of the basal ganglia are the caudate nucleus, putamen, and globus pallidus Image File history File linksMetadata No higher resolution available. ...

Schematic representation of the chief ganglionic categories (I to V). Image File history File links Gray678. ...

External links

• Basal+ganglia at eMedicine Dictionary
• Imaging of Basal Ganglia at USUHS