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The basal ganglia (or basal nuclei) are a group of nuclei
Nucleus (neuroanatomy)

In neuroanatomy, a nucleus is a brain structure consisting of a relatively compact cluster of neurons. It is one of the two most common forms of nerve cell organization, the other being layered structures such as the cerebral cortex or cerebellum....
 in the brain
Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as cnidarian and echinoderm have a decentralized nervous system without a brain, while sponges lack any nervous system at all....
 interconnected with the cerebral cortex
Cerebral cortex

The cerebral cortex is a structure within the brain that plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness....
, thalamus
Thalamus

The thalamus is a pair and symmetric part of the brain. It constitutes the main part of the diencephalon....
 and brainstem. Mammal
Mammal

Mammals are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, with which they feed their young....
ian basal ganglia are associated with a variety of functions: motor control, cognition, emotions, and learning
Learning

Learning is acquiring new knowledge, behaviors, skills, Value s, preferences or understanding, and may involve synthesizing different types of information....
. In modern use the term 'ganglia' is in this instance considered a misnomer; 'ganglion' refers to concentrations of neural nuclei in the periphery
Peripheral nervous system

The peripheral nervous system resides or extends outside the central nervous system , which consists of the brain and spinal cord. The main function of the PNS is to connect the CNS to the limbs and organs....
 only (for example those of the autonomic nervous system
Autonomic nervous system

The autonomic nervous system is the part of the peripheral nervous system that acts as a control system, maintaining human homeostasis in the body....
), and the term 'basal nuclei' is preferred.

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

The first anatomical
Anatomy

Anatomy is a branch of biology that is the consideration of the body plan. It is a general term that includes human anatomy, animal anatomy and plant anatomy ....
 identification of distinct subcortical structures was published by Thomas Willis
Thomas Willis

Thomas Willis was an English people doctor who played an important part in the history of anatomy, neurology and psychiatry. He was a founding member of the Royal Society....
 in 1664.






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The basal ganglia (or basal nuclei) are a group of nuclei
Nucleus (neuroanatomy)

In neuroanatomy, a nucleus is a brain structure consisting of a relatively compact cluster of neurons. It is one of the two most common forms of nerve cell organization, the other being layered structures such as the cerebral cortex or cerebellum....
 in the brain
Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as cnidarian and echinoderm have a decentralized nervous system without a brain, while sponges lack any nervous system at all....
 interconnected with the cerebral cortex
Cerebral cortex

The cerebral cortex is a structure within the brain that plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness....
, thalamus
Thalamus

The thalamus is a pair and symmetric part of the brain. It constitutes the main part of the diencephalon....
 and brainstem. Mammal
Mammal

Mammals are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, with which they feed their young....
ian basal ganglia are associated with a variety of functions: motor control, cognition, emotions, and learning
Learning

Learning is acquiring new knowledge, behaviors, skills, Value s, preferences or understanding, and may involve synthesizing different types of information....
. In modern use the term 'ganglia' is in this instance considered a misnomer; 'ganglion' refers to concentrations of neural nuclei in the periphery
Peripheral nervous system

The peripheral nervous system resides or extends outside the central nervous system , which consists of the brain and spinal cord. The main function of the PNS is to connect the CNS to the limbs and organs....
 only (for example those of the autonomic nervous system
Autonomic nervous system

The autonomic nervous system is the part of the peripheral nervous system that acts as a control system, maintaining human homeostasis in the body....
), and the term 'basal nuclei' is preferred.

History

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

The first anatomical
Anatomy

Anatomy is a branch of biology that is the consideration of the body plan. It is a general term that includes human anatomy, animal anatomy and plant anatomy ....
 identification of distinct subcortical structures was published by Thomas Willis
Thomas Willis

Thomas Willis was an English people doctor who played an important part in the history of anatomy, neurology and psychiatry. He was a founding member of the Royal Society....
 in 1664. For many years, the term corpus striatum
Striatum

The striatum is a subcortical part of the telencephalon/cerebrum. It is the major input station of the basal ganglia system. Anatomically, the striatum is the caudate nucleus and the putamen....
 was used to describe a large group of subcortical elements, some of which were later discovered to be functionally unrelated. Additionally, the putamen
Putamen

The putamen is a round structure located at the base of the forebrain . The putamen and caudate nucleus together form the dorsal striatum. It is also one of the structures that comprises the basal ganglia....
 and the caudate nucleus
Caudate nucleus

The caudate nucleus is a nucleus located within the basal ganglia of the brains of many animal species. The caudate, originally thought to primarily be involved with control of voluntary movement, is now known to be an important part of the brain's learning and memory system....
 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
Lentiform nucleus

The lentiform nucleus or lenticular nucleus comprises the putamen and the globus pallidus within the basal ganglia. It is a large, cone-shaped mass of gray matter just lateral to the internal capsule....
 on the fig.).

Pioneering work by Cécile and Oskar Vogt (1941) greatly simplified the description of the basal ganglia by proposing the term striatum
Striatum

The striatum is a subcortical part of the telencephalon/cerebrum. It is the major input station of the basal ganglia system. Anatomically, the striatum is the caudate nucleus and the putamen....
 to describe the group of structures consisting of the caudate nucleus, the putamen and the mass linking them ventrally
Anatomical terms of location

Standard anatomical terms of location are employed in sciences dealing with the anatomy of animals to avoid ambiguities which might otherwise arise....
, the nucleus accumbens
Nucleus accumbens

The nucleus accumbens , also known as the accumbens nucleus or as the nucleus accumbens septi , is a collection of neurons within the forebrain....
.

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
Substantia nigra

The substantia nigra is a brain structure located in the mesencephalon that plays an important role in reward, addiction, and movement. Substantia nigra is Latin for "black substance", as parts of the substantia nigra appear darker than neighboring areas due to high levels of melanin in dopaminergic neurons....
 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
Internal capsule

The internal capsule is an area of white matter in the brain that separates the caudate nucleus and the thalamus from the lenticular nucleus. The internal capsule contains both ascending and descending axons....
.

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
Subthalamic nucleus

The subthalamic nucleus is a small lens-shaped Nucleus in the brain where it is a part of the basal ganglia system. As suggested by its name, the subthalamic nucleus is located Anatomical terms of location to the thalamus....
, 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.

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
Chorea

Chorea may refer to:*Chorea , ancient Greek dance*Chorea , medical disorder involving involuntary movement...
, athetosis
Athetosis

Athetosis is a continuous stream of slow, sinuous, writhing movements, typically of the hands and Foot. Movements typical to athetosis are sometimes called athetoid movements....
, Parkinson's disease
Parkinson's disease

Parkinson's disease is a degenerative disorder of the central nervous system that often impairs the sufferer's motor skills and speech, as well as other functions....
).

Anatomical subdivisions

Basal Ganglia Coronal Sections Large
The five individual nuclei that make up the primate
Primate

A primate is a member of the biological order Primates , the group that contains lemurs, the Aye-aye, Lorisidaes, galagos, tarsiers, monkeys, and apes, with the last category including humans....
 basal ganglia, along with their major subdivisions, are:

rostral
Rostral

Rostral can refer to:* Anatomical terms of location#Directions, Top or cephaled, as opposed to caudal or down.* Rostral bone* Rostral column, a monumental scaled column, frequently decorated with ship bows...
  • the striatum
    Striatum

    The striatum is a subcortical part of the telencephalon/cerebrum. It is the major input station of the basal ganglia system. Anatomically, the striatum is the caudate nucleus and the putamen....
    , which consists of
    • putamen
      Putamen

      The putamen is a round structure located at the base of the forebrain . The putamen and caudate nucleus together form the dorsal striatum. It is also one of the structures that comprises the basal ganglia....
    • caudate nucleus
      Caudate nucleus

      The caudate nucleus is a nucleus located within the basal ganglia of the brains of many animal species. The caudate, originally thought to primarily be involved with control of voluntary movement, is now known to be an important part of the brain's learning and memory system....
  • external segment of the globus pallidus
    Globus pallidus

    The globus pallidus is a sub-Cerebral cortex structure of the brain. It is a major element of the basal ganglia system. In this system, it is a major constituent of the basal ganglia core, which consists of the striatum and its direct targets: globus pallidus and substantia nigra....
     (GPe)
  • internal segment of the globus pallidus (GPi)


caudal
  • subthalamic nucleus
    Subthalamic nucleus

    The subthalamic nucleus is a small lens-shaped Nucleus in the brain where it is a part of the basal ganglia system. As suggested by its name, the subthalamic nucleus is located Anatomical terms of location to the thalamus....
     (STN)
  • substantia nigra
    Substantia nigra

    The substantia nigra is a brain structure located in the mesencephalon that plays an important role in reward, addiction, and movement. Substantia nigra is Latin for "black substance", as parts of the substantia nigra appear darker than neighboring areas due to high levels of melanin in dopaminergic neurons....
     (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.

Two coronal sections are used to show the basal ganglia; the STN and substantia nigra lie deeper back in the brain (more caudal
Anatomical terms of location

Standard anatomical terms of location are employed in sciences dealing with the anatomy of animals to avoid ambiguities which might otherwise arise....
). Images show two schematic coronal
Anatomical terms of location

Standard anatomical terms of location are employed in sciences dealing with the anatomy of animals to avoid ambiguities which might otherwise arise....
 cross-sections of the human
Human

A human being, also human or man, is a member of a species of bipedalism primates in the family Hominidae . Mitochondrial DNA evidence indicates that modern humans originated in east Africa about 200,000 years ago....
 brain with nuclei of the basal ganglia labeled on the right side.

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 amniote
Amniote

The amniotes are a group of tetrapod vertebrates that have a terrestrially adapted egg. They include the Synapsida and Sauropsida . Amniote embryos, whether laid as eggs or carried by the female, are protected and aided by several extensive membranes....
s (mammals, birds, and reptiles) and amphibian
Amphibian

Amphibians , such as frogs, toads, salamanders, newts and caecilians, are cold-blooded animals that metamorphose from a juvenile, water-breathing form to an adult, air-breathing form....
s. The anatomical connections of these nuclei and their pharmacology
Pharmacology

Pharmacology is the study of drug action. More specifically it is the study of the interactions that occur between a living organism and exogenous chemicals that alter normal biochemical function....
 also appear relatively conserved. Non-tetrapod
Tetrapod

Tetrapods are vertebrate animals having four feet, legs or leglike appendages. Amphibians, reptiles, dinosaurs/birds, and mammals are all tetrapods, and even the limbless snakes are tetrapods by descent....
 vertebrates such as fish also display basal ganglia-like structures, although the data are less clear in this case.

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 rodent
    Rodent

    Rodentia is an Order of mammals also known as rodents, characterised by two continuously growing Incisors#The_Rodent_incisor in the upper and lower jaws which must be kept short by gnawing....
    s.
  • 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
Ansa lenticularis

The ansa lenticularis is a part of the brain, making up the superior layer of the Substantia innominata. 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....
--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
Gerald Edelman

Gerald Maurice Edelman is an American biology who won the 1972 Nobel Prize in Physiology or Medicine for his work on the immune system. Edelman's Nobel Prize-winning research concerned discovery of the structure of antibody molecules....
 as a critical basis for the emergence of primary consciousness
Primary consciousness

Primary consciousness is a term coined by the American biologist Gerald Edelman to describe the ability, found in humans and some animals, to integrate observed events with memory to create an awareness of the present and immediate past of the world around them....
 in the theory of Neural Darwinism
Neural Darwinism

Neural Darwinism, a large scale theory of brain function by Gerald Edelman, was initially published in 1978, in a book called The Mindful Brain ....
.

Connections

Basal Ganglia Classic
Basal ganglia connectivity is illustrated in the figure.

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
Cerebral cortex

The cerebral cortex is a structure within the brain that plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness....
, mainly from the motor
Motor cortex

Motor cortex is a term that describes regions of the cerebral cortex involved in the planning, control, and execution of voluntary motion functions....
 and prefrontal
Prefrontal cortex

The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the primary motor cortex and premotor cortex areas....
 cortices.

The circuitry
Neural network

Traditionally, the term neural network had been used to refer to a network or circuit of neuron. The modern usage of the term often refers to artificial neural networks, which are composed of artificial neurons or nodes....
 of the basal ganglia is often divided into two major pathways, the direct pathway and the indirect pathway:

Pathway Path # inhibitory pathways (-) Description Dopamine receptor
Dopamine receptor

Dopamine receptors are a class of metabotropic receptor G protein-coupled receptors that are prominent in the vertebrate central nervous system ....
s |- | Direct (stimulatory)		 striatum-
?GPi/SNr-
?thalamus+
?cortex 		2 (even) Cortical activity that excites cells in the striatum that participate in the direct pathway leads to inhibition of areas of the GPi and SNr, which in turn removes their tonic inhibition from the thalamus. (This removal of inhibition by inhibition is called "disinhibition".) - | Indirect (inhibitory) striatum-
?GPe -
?STN +
?GPi/SNr-
?thalamus+
?cortex 		3 (odd) In contrast, cortical activity that excites the striatal cells in the indirect pathway is thought to inhibit the thalamus (by inhibiting the disinhibition). D2


Dopamine
Dopamine

Dopamine is a neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In the human brain, this phenethylamine functions as a neurotransmitter, activating the five types of dopamine receptors ? D1, D2, D3, D4 and D5, and their variants....
 from the substantia nigra
Substantia nigra

The substantia nigra is a brain structure located in the mesencephalon that plays an important role in reward, addiction, and movement. Substantia nigra is Latin for "black substance", as parts of the substantia nigra appear darker than neighboring areas due to high levels of melanin in dopaminergic neurons....
 pars compacta stimulates all of the dopamine receptor
Dopamine receptor

Dopamine receptors are a class of metabotropic receptor G protein-coupled receptors that are prominent in the vertebrate central nervous system ....
s, 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.

Neurotransmitters


The different types of neuron of the basal ganglia biosynthesize different neurotransmitter
Neurotransmitter

Neurotransmitters are chemistry which relay, amplify and modulate signals between a neuron and another cell . Neurotransmitters are packaged into vesicles that cluster beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft, where they bind to receptors in the membrane on the postsynaptic side of...
s.

Structure Neurotransmitter Description Disorders >- | Striatum/neostriatum GABA
Gabâ

Gab? or gabaa, for the Cebuano people , is the concept of a non-human and non-divine, imminent Retributive justice. A sort of negative karma, it is generally seen as an evil effect on a person because of their wrongdoings or transgressions....
 		 Medium neurons, the principal cells, are inhibitory Huntington's disease
Huntington's disease

Huntington's disease, also called Huntington's Chorea , chorea major, or HD, is a genetics Neurodegenerative disease characterized after onset by uncoordinated, jerky body movements and a decline in some mental abilities....
 |- | Substantia nigra 		dopamine
Dopamine

Dopamine is a neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In the human brain, this phenethylamine functions as a neurotransmitter, activating the five types of dopamine receptors ? D1, D2, D3, D4 and D5, and their variants....
 		 The substantia nigra pars compacta (SNc) primarily targets the striatum with this neurotransmitter (shown as the magenta connection in the classic connectivity diagram above). Disruption in the biosynthesis or transmission of dopamine
Dopamine

Dopamine is a neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In the human brain, this phenethylamine functions as a neurotransmitter, activating the five types of dopamine receptors ? D1, D2, D3, D4 and D5, and their variants....
 can lead to serious motor and cognitive deficits, such as occurs in Parkinson's disease
Parkinson's disease

Parkinson's disease is a degenerative disorder of the central nervous system that often impairs the sufferer's motor skills and speech, as well as other functions....
. |- | Globus pallidus 		GABA
Gabâ

Gab? or gabaa, for the Cebuano people , is the concept of a non-human and non-divine, imminent Retributive justice. A sort of negative karma, it is generally seen as an evil effect on a person because of their wrongdoings or transgressions....
 		 The globus pallidus contains an internal segment and an external segment. The internal segment projects to the thalamus, whereas the external segment projects to the subthalamic nucleus. Tourette's syndrome |- | Subthalamic nucleus glutamate The neurons of the subthalmic nucleus excite neurons of the internal globus pallidus. Damage to the subthalmic nucleus may result in hemiballismus
Hemiballismus

Hemiballismus is a very rare movement disorder. It is five hundred times rarer than Parkinson?s disease. Its effects can sometimes be severe enough to prevent patients from being able to perform daily functions....
.


Other disorders linked with the basal ganglia

  • Attention-deficit hyperactivity disorder
    Attention-deficit hyperactivity disorder

    Attention-deficit/hyperactivity disorder is a wikt:neurobehavioral wikt:developmental wikt:disorder. It affects about 3 to 5% of children with symptoms starting before seven years of age....
     (ADHD)
  • Athymhormic syndrome
    Athymhormic syndrome

    Athymhormic syndrome, or psychic akinesia, is a rare neurology syndrome characterized by extreme passivity, apathy, and a profound generalized loss of self-motivation....
     (PAP syndrome)
  • Cerebral palsy
    Cerebral palsy

    Cerebral palsy is an umbrella term encompassing a group of non-progressive illness, non-Infectious diseases conditions that cause physical disability in Human development ....
    : basal ganglia damage during second and third trimester of pregnancy
  • Dystonia
    Dystonia

    Dystonia is a neurology movement disorder in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. The disorder may be Heredity or caused by other factors such as Birth trauma or other physical trauma, infection, poisoning or reaction to Medication....
  • Fahr's disease
  • Foreign accent syndrome
    Foreign accent syndrome

    Foreign accent syndrome is a rare medical condition that usually occurs as a rare side effect of severe brain injury, such as a stroke or a head injury ....
     (FAS)
  • Huntington's disease
    Huntington's disease

    Huntington's disease, also called Huntington's Chorea , chorea major, or HD, is a genetics Neurodegenerative disease characterized after onset by uncoordinated, jerky body movements and a decline in some mental abilities....
  • Lesch-Nyhan syndrome
    Lesch-Nyhan syndrome

    Lesch-Nyhan syndrome , also known as Nyhan?s syndrome or Kelley-Seegmiller syndrome, is a rare, inherited disorder caused by a deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase , produced by mutations in the HPRT gene....
  • Obsessive-compulsive disorder
    Obsessive-compulsive disorder

    Obsessive-compulsive disorder is a mental disorder most commonly characterized by Intrusive thoughts, repetitive thoughts resulting in compulsive behaviors and mental acts that the person feels driven to perform, according to rules that must be applied rigidly, aimed at reducing anxiety by preventing some dreaded event or by resolving a more...
  • Parkinson's disease
    Parkinson's disease

    Parkinson's disease is a degenerative disorder of the central nervous system that often impairs the sufferer's motor skills and speech, as well as other functions....
  • Tourette's disorder
    Tourette syndrome

    Tourette syndrome is an heredity Neuropsychiatry disorder with onset in childhood, characterized by the presence of multiple physical tics and at least one vocal tic; these tics characteristically wax and wane....
  • Tardive dyskinesia
    Tardive dyskinesia

    Tardive dyskinesia is a variety of Dyskinesia manifesting as a side effect of long-term or high-dose use of dopamine antagonists, usually antipsychotics....
    , caused by chronic antipsychotic
    Antipsychotic

    Antipsychotics are a group of psychoactive drugs commonly but not exclusively used to treat psychosis, which is typified by schizophrenia. Over time a wide range of antipsychotics have been developed....
     treatment
  • Stuttering
    Stuttering

    Stuttering, also known as stammering in the United Kingdom, is a speech disorder in which the flow of Speech communication is disrupted by involuntary repetitions and prolongations of sounds, syllables, words or phrases, and involuntary silent pauses or blocks in which the stutterer is unable to produce sounds....
  • Spasmodic dysphonia
    Spasmodic dysphonia

    Spasmodic dysphonia is a voice disorder characterized by involuntary movements of one or more muscles of the larynx during speech....
  • Wilson's disease
    Wilson's disease

    Wilson's disease or hepatolenticular degeneration is an autosomal recessive genetic disorder in which copper accumulates in biological tissue; this manifests as neurology or psychiatry symptoms and liver disease....
  • Blepharospasm
    Blepharospasm

    A blepharospasm , is any abnormal tic or twitch of the eyelid.It normally refers to benign essential blepharospasm, a focal dystonia - a neurological movement disorder involving involuntary and sustained muscle contractions of the muscles around the eyes....


Terminology

As it refers to a group of nuclei, the term "basal ganglia" is plural (the singular of ganglia is ganglion
Ganglion

In anatomy, a ganglion is a biological tissue.Cells found in a ganglion are called ganglion cells, though this term is also sometimes used to refer specifically to Retinal ganglion cells....
). However this is a misnomer
Misnomer

A misnomer is a term which suggests an interpretation that is known to be untrue. Such incorrect terms sometimes derived their names because of the form, action, or origin of the subject?becoming named popularly or widely referenced?long before their true natures were known....
, as "ganglion" refers to a somatic
Soma (biology)

The soma, or cyton or perikaryon, is the bulbous end of a neuron, containing the cell nucleus. The word soma is Greek language, meaning "body"; the soma of a neuron is often called the "Cell body"....
 cluster within the peripheral nervous system
Peripheral nervous system

The peripheral nervous system resides or extends outside the central nervous system , which consists of the brain and spinal cord. The main function of the PNS is to connect the CNS to the limbs and organs....
, whereas the basal ganglia are within the central nervous system
Central nervous system

The central nervous system is the part of the nervous system that functions to coordinate the activity of all parts of the bodies of multicellular organisms....
 (CNS). A somatic cluster within the CNS is referred to as a nucleus, so some neuroanatomists
Neuroanatomy

Neuroanatomy is the branch of anatomy that studies the anatomical organization of the nervous system. In vertebrate animals, the peripheral nervous system that the myriad nerves take from the brain to the rest of the body , and the internal structure of the brain in particular, are both extremely elaborate....
 refer to the basal ganglia as the "basal nuclei".

See also

  • Anatomical subdivisions and connections of the basal ganglia
  • Nathaniel A. Buchwald
    Nathaniel A. Buchwald

    Nathaniel A. Buchwald was an American neuroscientist, educator and administrator, who was Professor of Psychiatry and Biobehavioral Sciences and Neurobiology at the University of California, Los Angeles ....
  • Primate basal ganglia system
    Primate basal ganglia system

    The primate basal ganglia system is a symmetrical major cerebral system that has only recently been recognized. In the past, part of it was presented as motor system or "extrapyramidal", complementary to the corticospinal tract system....


Additional images


External links

  • at USUHS
    Uniformed Services University of the Health Sciences

    The Uniformed Services University of the Health Sciences is a health science university run by the Federal government of the United States. The primary mission of the school is to prepare graduates for service to the U.S....