Caudate nucleus
Encyclopedia
The caudate nucleus is a nucleus
located within the basal ganglia
of the brain
s of many animal species. The caudate nucleus is an important part of the brain's learning and memory system.
. There is a caudate nucleus within each hemisphere of the brain. Individually, they resemble a C-shape structure with a wider "head" (caput in Latin) at the front, tapering to a "body" (corpus) and a "tail" (cauda). Sometimes a part of the caudate nucleus is referred to as the "knee" (genu).
The head and body of the caudate nucleus form part of the floor of the anterior horn of the lateral ventricle. After the body travels briefly towards the back of the head, the tail curves back toward the anterior, forming the roof of the inferior horn of the lateral ventricle. This means that a coronal (on the same plane as the face
) section that cuts through the tail will also cross the body and head of the caudate nucleus.
The caudate nucleus is related anatomically to a number of other structures. It is separated from the lenticular nucleus (made up of the globus pallidus
and the putamen
) by the anterior limb of the internal capsule
. Together the caudate and putamen form the dorsal striatum
.
neurons. These neurons originate mainly from the ventral tegmental area (VTA) and the substantia nigra pars compacta
(SNc). There are also additional inputs from various association cortices.
The caudate nucleus was initially thought to primarily be involved with control of voluntary movement. More recently, it has been demonstrated that the caudate is highly involved in learning and memory, particularly regarding feedback processing. In general, it has been demonstrated that neural activity will be present within the caudate while an individual is receiving feedback. People with hyperthymesia
appear to have slight increases in the sizes of the caudate nucleus as well as of the temporal lobe
of the cortex.
that governs the comprehension and articulation of words as they are switched between languages.
. It is difficult to see how such a system can operate without some mechanism to prevent explosive activation. There is some indirect evidence that the caudate may perform this regulatory role by measuring the general activity of cerebral cortex
and controlling the threshold potential
.
and the orbitofrontal cortex
.
A neuroimaging
study with positron emission tomography
found that the right caudate nucleus had the largest change in glucose metabolism after patients had been treated with paroxetine
. Recent SDM meta-analyses
of voxel-based morphometry studies comparing people with OCD and healthy controls have found people with OCD to have increased grey matter
volumes in bilateral lenticular nuclei, extending to the caudate nuclei, while decreased grey matter volumes in bilateral dorsal medial frontal
/anterior cingulate
gyri. These findings contrast with those in people with other anxiety disorders, who evince decreased (rather than increased) grey matter
volumes in bilateral lenticular / caudate nuclei, while also decreased grey matter volumes in bilateral dorsal medial frontal
/anterior cingulate
gyri.
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 cerebellar cortex. In anatomical sections, a nucleus shows up...
located within the basal ganglia
Basal ganglia
The basal ganglia are a group of nuclei of varied origin in the brains of vertebrates that act as a cohesive functional unit. They are situated at the base of the forebrain and are strongly connected with the cerebral cortex, thalamus and other brain areas...
of the brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
s of many animal species. The caudate nucleus is an important part of the brain's learning and memory system.
Anatomy
The caudate nuclei are located near the center of the brain, sitting astride the thalamusThalamus
The thalamus is a midline paired symmetrical structure within the brains of vertebrates, including humans. It is situated between the cerebral cortex and midbrain, both in terms of location and neurological connections...
. There is a caudate nucleus within each hemisphere of the brain. Individually, they resemble a C-shape structure with a wider "head" (caput in Latin) at the front, tapering to a "body" (corpus) and a "tail" (cauda). Sometimes a part of the caudate nucleus is referred to as the "knee" (genu).
The head and body of the caudate nucleus form part of the floor of the anterior horn of the lateral ventricle. After the body travels briefly towards the back of the head, the tail curves back toward the anterior, forming the roof of the inferior horn of the lateral ventricle. This means that a coronal (on the same plane as the face
Face
The face is a central sense organ complex, for those animals that have one, normally on the ventral surface of the head, and can, depending on the definition in the human case, include the hair, forehead, eyebrow, eyelashes, eyes, nose, ears, cheeks, mouth, lips, philtrum, temple, teeth, skin, and...
) section that cuts through the tail will also cross the body and head of the caudate nucleus.
The caudate nucleus is related anatomically to a number of other structures. It is separated from the lenticular nucleus (made up of the globus pallidus
Globus pallidus
The globus pallidus also known as paleostriatum, is a sub-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...
and 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. Through various pathways, the putamen is connected to the substantia nigra and globus pallidus...
) by the anterior limb of 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....
. Together the caudate and putamen form the dorsal striatum
Striatum
The striatum, also known as the neostriatum or striate nucleus, is a subcortical part of the forebrain. It is the major input station of the basal ganglia system. The striatum, in turn, gets input from the cerebral cortex...
.
Neurochemistry
The caudate nucleus is highly innervated by dopamineDopamine
Dopamine is a catecholamine neurotransmitter present in a wide variety of animals, including both vertebrates and invertebrates. In the brain, this substituted phenethylamine functions as a neurotransmitter, activating the five known types of dopamine receptors—D1, D2, D3, D4, and D5—and their...
neurons. These neurons originate mainly from the ventral tegmental area (VTA) and the substantia nigra pars compacta
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...
(SNc). There are also additional inputs from various association cortices.
Learning and memory
Historically, the basal ganglia as a whole have been implicated in higher-order motor control.The caudate nucleus was initially thought to primarily be involved with control of voluntary movement. More recently, it has been demonstrated that the caudate is highly involved in learning and memory, particularly regarding feedback processing. In general, it has been demonstrated that neural activity will be present within the caudate while an individual is receiving feedback. People with hyperthymesia
Hyperthymesia
Hyperthymesia, also known as piking or hyperthymestic syndrome, is a condition where the affected individual has a superior autobiographical memory. "Thymesia" comes from the Greek word θύμησις thymesis, meaning "memory"...
appear to have slight increases in the sizes of the caudate nucleus as well as of the temporal lobe
Temporal lobe
The temporal lobe is a region of the cerebral cortex that is located beneath the Sylvian fissure on both cerebral hemispheres of the mammalian brain....
of the cortex.
Emotion
The caudate nucleus has been implicated in responses to visual beauty, and has been suggested as one of the "neural correlates of romantic love".Language comprehension
The left caudate in particular has been suggested to have a relationship with the thalamusThalamus
The thalamus is a midline paired symmetrical structure within the brains of vertebrates, including humans. It is situated between the cerebral cortex and midbrain, both in terms of location and neurological connections...
that governs the comprehension and articulation of words as they are switched between languages.
Threshold control
The brain contains large collections of neurons reciprocally connected by excitatory synapses, thus forming large network of elements with positive feedbackPositive feedback
Positive feedback is a process in which the effects of a small disturbance on a system include an increase in the magnitude of the perturbation. That is, A produces more of B which in turn produces more of A. In contrast, a system that responds to a perturbation in a way that reduces its effect is...
. It is difficult to see how such a system can operate without some mechanism to prevent explosive activation. There is some indirect evidence that the caudate may perform this regulatory role by measuring the general activity of cerebral cortex
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
and controlling the threshold potential
Threshold potential
The threshold potential is the membrane potential to which a membrane must be depolarized to initiate an action potential.It often can be between −40 and -55 mV, but it can vary based upon several factors...
.
Role in obsessive compulsive disorder
It has been theorized that the caudate nucleus may be dysfunctional in persons with obsessive compulsive disorder (OCD), in that it may perhaps be unable to properly regulate the transmission of information regarding worrying events or ideas between the thalamusThalamus
The thalamus is a midline paired symmetrical structure within the brains of vertebrates, including humans. It is situated between the cerebral cortex and midbrain, both in terms of location and neurological connections...
and the orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...
.
A neuroimaging
Neuroimaging
Neuroimaging includes the use of various techniques to either directly or indirectly image the structure, function/pharmacology of the brain...
study with positron emission tomography
Positron emission tomography
Positron emission tomography is nuclear medicine imaging technique that produces a three-dimensional image or picture of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide , which is introduced into the body on a...
found that the right caudate nucleus had the largest change in glucose metabolism after patients had been treated with paroxetine
Paroxetine
Paroxetine is an SSRI antidepressant. Marketing of the drug began in 1992 by the pharmaceutical company SmithKline Beecham, now GlaxoSmithKline...
. Recent SDM meta-analyses
Signed differential mapping
Signed differential mapping or SDM is a statistical technique for meta-analyzing studies on differences in brain activity or structure which used neuroimaging techniques such as fMRI, VBM, DTI or PET...
of voxel-based morphometry studies comparing people with OCD and healthy controls have found people with OCD to have increased grey matter
Grey matter
Grey matter is a major component of the central nervous system, consisting of neuronal cell bodies, neuropil , glial cells and capillaries. Grey matter contains neural cell bodies, in contrast to white matter, which does not and mostly contains myelinated axon tracts...
volumes in bilateral lenticular nuclei, extending to the caudate nuclei, while decreased grey matter volumes in bilateral dorsal medial frontal
Medial frontal gyrus
The superior frontal gyrus is situated above the superior frontal sulcus and is continued on to the medial surface of the hemisphere, the medial frontal gyrus...
/anterior cingulate
Anterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
gyri. These findings contrast with those in people with other anxiety disorders, who evince decreased (rather than increased) grey matter
Grey matter
Grey matter is a major component of the central nervous system, consisting of neuronal cell bodies, neuropil , glial cells and capillaries. Grey matter contains neural cell bodies, in contrast to white matter, which does not and mostly contains myelinated axon tracts...
volumes in bilateral lenticular / caudate nuclei, while also decreased grey matter volumes in bilateral dorsal medial frontal
Medial frontal gyrus
The superior frontal gyrus is situated above the superior frontal sulcus and is continued on to the medial surface of the hemisphere, the medial frontal gyrus...
/anterior cingulate
Anterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
gyri.
External links
- Diagram at uni-tuebingen.de
- NIF Search - Caudate Nucleus via the Neuroscience Information FrameworkNeuroscience Information FrameworkThe Neuroscience Information Framework is a repository of global neuroscience web resources, including experimental, clinical, and translational neuroscience databases, knowledge bases, atlases, and genetic/genomic resources.-Description:...
