| Brain: Internal capsule | ||
|---|---|---|
 |
||
| Horizontal section of right cerebral hemisphere. (Capsula interna labeled at upper left. ) | ||
 |
||
| The motor tract. | ||
| Latin | capsula interna | |
| Gray's | subject #189 836 | |
| NeuroNames | hier-180 | |
| Dorlands/Elsevier | c_07/12211417 | |
The internal capsule is an area of white matter in the brain that separates the caudate nucleus and the thalamus from the lenticular nucleus. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. This is a list of the subjects in Gray's Anatomy: IX Neurology NeuroNames is a system of nomenclature for the human and/or macaque Brain. Elsevier, the world's largest Publisher of Medical and Scientific literature, forms part of the Reed Elsevier group White matter is one of the three main solid components of the Central nervous system. The brain is the center of the Nervous system in animals All Vertebrates and the majority of Invertebrates have a brain The caudate nucleus is a nucleus located within the Basal ganglia of the Brains of many animal species The thalamus (from Greek θάλαμος = room chamber, IPA= /ˈθæləməs/ is a pair and symmetric part of the brain The lentiform nucleus or lenticular nucleus comprises the Putamen and the Globus pallidus within the Basal ganglia.
It consists of axonal fibres that run between the cerebral cortex and the pyramids of the medulla. An axon or nerve fiber is a long slender projectionof a nerve cell or Neuron, that conducts electrical impulses away from the neuron's Cell The cerebral cortex is a structure within the Brain that plays a key role in Memory, Attention, perceptual Awareness, Thought, The anterior or ventral portion of the Medulla oblongata is named the pyramid and lies between the Anterior median fissure and the Antero-lateral sulcus
Contents |
Components
The internal capsule is V-shaped when cut both coronally (on the same plane as the face) and horizontally/transversely (the same plane as the brim of a top hat). For the item of clothing see Top hat. For the fictional TUGS character see Top Hat (TUGS.
When cut horizontally:
- the bend in the V is called the "genu".
- the part in front of the genu is the "anterior limb". The anterior limb of internal capsule (or frontal part) contains (1 fibers running from the Thalamus to the Frontal lobe; (2 or crus anterius.
- the part behind the genu is called the "posterior limb" or crus posterius. The posterior limb of internal capsule (or occipital part) is the portion of the Internal capsule posterior to the genu.
There is also a retrolenticular and a sublenticular part to the internal capsule.
Fibers
- The posterior limb of the internal capsule contains corticospinal fibers and sensory fibers from the body. The corticospinal or pyramidal tract is a massive collection of Axons that travel between the Cerebral cortex of the Brain and the Spinal
- The genu contains corticobulbar fibers, which run between the cortex and the brainstem. The corticobulbar (or corticonuclear) tract is a White matter pathway connecting the Cerebral cortex to the Brainstem (the term "bulbar" The cerebral cortex is a structure within the Brain that plays a key role in Memory, Attention, perceptual Awareness, Thought, The brain stem (or brainstem) is the lower part of the Brain, adjoining and structurally continuous with the Spinal cord.
- The anterior limb of the internal capsule contains:
- 1) frontopontine (corticofugal) fibers project from frontal cortex to pons;
- 2) thalamocortico fibers connect the medial and anterior nuclei of the thalamus to the frontal lobes (these are severed during a prefrontal lobotomy). The frontopontine fibers are situated in the medial fifth of the base of the Cerebral peduncles; they arise from the cells of the Frontal lobe and end in the nuclei The frontal lobe is an area in the Brain of Mammals It is located at the front of each Cerebral hemisphere and positioned anterior to (in front of the The pons (sometimes pons Varolii after Costanzo Varolio) is a structure located on the Brain stem. Thalamocortical radiations are the fibers between the Thalamus and the Cerebral cortex. The medial dorsal nucleus (or dorsomedial nucleus of thalamus) is a large nucleus in the Thalamus. The anterior nuclei of thalamus (or anterior nuclear group) are collection of nuclei at the rostral end of the dorsal Thalamus. The frontal lobe is an area in the Brain of Mammals It is located at the front of each Cerebral hemisphere and positioned anterior to (in front of the A lobotomy ( Greek: lobos Lobe of Brain, tomos "cut/slice" is a form of Psychosurgery, also known as a leukotomy or
- The retrolenticular part contains fibers from the optic system, coming from the lateral geniculate nucleus of the thalamus. The lateral geniculate nucleus ( LGN) of the Thalamus is a part of the Brain, which is the primary processor of visual information received from the The thalamus (from Greek θάλαμος = room chamber, IPA= /ˈθæləməs/ is a pair and symmetric part of the brain More posteriorly, this becomes the optic radiation. The optic radiation (also known as the geniculo-calcarine tract or as the geniculostriate pathway) is a collection of Axons from Relay neurons Some fibers from the medial geniculate nucleus (which carry auditory information) also pass in the retrolenticular internal capsule, but most are in the sublenticular part. The Medial Geniculate Nucleus or Medial Geniculate Body (MGB is part of the auditory Thalamus and represents the thalamic relay between the Inferior colliculus
Blood supply
Blood supply is similar to the other structures of the region. mainly Striate arteries, which come off the middle cerebral artery, enter through the anterior perforated substance in the base of the brain. Striate arteries or Ganglionic arteries arise from the Middle cerebral artery and supplies deep structures in the Cerebrum including the Internal capsule The middle cerebral artery (MCA is one of the three major paired arteries that supplies Blood to the Brain. The anterior perforated substance is an irregularly quadrilateral area in front of the Optic tract and behind the Olfactory trigone, from which it is separated by
The capsular branch of posterior cerebral artery which is called the thalamogeniculate artery supplies the posterior limb of the capsule, while the anterior limb is supplied by striate arteries from the middle cerebral artery and Heubner's artery which is the capsular branch of anterior cerebral artery. In Human anatomy, the posterior cerebral artery is the Blood vessel that supplies oxygenated Blood to the posterior aspect of the brain ( Occipital Also known as the 'arteria thalamogeniculata' the thalamogeniculate Artery is a branch of the Posterior cerebral artery supplying the medial and lateral Geniculate The middle cerebral artery (MCA is one of the three major paired arteries that supplies Blood to the Brain. In Human anatomy, each anterior cerebral artery supplies Oxygen to most medial portions of Frontal lobes and Superior medial parietal lobes
Pathology
Infarctions to the internal capsule tend to be small, punctate lesions. In Medicine, an infarction is the process resulting in a Macroscopic area of necrotic tissue in some organ caused by loss of adequate Blood supply A lesion is any abnormal tissue found on or in an organism usually damaged by disease or trauma
They can affect sensory and motor systems on the opposite side of the body, and possibly eyesight (to the contralateral visual field). In Psychology, visual perception is the ability to interpret information from Visible light reaching the Eyes The resulting Perception is also
Hearing should not be affected in a single capsule lesion, as this information crosses over to both sides of the brain while in the brainstem.
Additional images
 Deep dissection of brain-stem. Lateral view. |
 Superficial dissection of brain-stem. Ventral view. |
 Coronal section of brain immediately in front of pons. |
 Coronal section of brain through intermediate mass of third ventricle. |
 Section of brain showing upper surface of temporal lobe. |
 Coronal section through anterior cornua of lateral ventricles. |
 Coronal section of brain through anterior commissure. |
 Dissection showing the course of the cerebrospinal fibers. |
 Diagram of the tracts in the internal capsule. |
 Human brain right dissected lateral view |
External links
BrainMaps is an NIH -funded interactive zoomable high-resolution digital brain atlas and virtual microscope that is based on more than 20 million megapixels (50 terabytes NeuroNames is a system of nomenclature for the human and/or macaque Brain. Elsevier, the world's largest Publisher of Medical and Scientific literature, forms part of the Reed Elsevier groupDapyx Software network: MP3 Explorer | Ebook Manager | Zenithic