Gracile nucleus

From Wikipedia, the free encyclopedia

(Redirected from Gracile tubercle)
Jump to: navigation, search
Brain: Gracile nucleus
Section of the medulla oblongata at the level of the decussation of the pyramids. Gracile nucleus is #8.
Dissection of brain-stem. Dorsal view. ("nucleus gracilis" is labeled on left, second from the bottom.)
Latin nucleus gracilis
Gray's subject #187 774
NeuroNames hier-763
Dorlands/Elsevier n_11/12581325

Located in the medulla oblongata, the gracile nucleus is one of the dorsal column nuclei that participates in the sensation of fine touch and proprioception. It contains second-order neurons of the dorsal column-medial lemniscus system which receive inputs from sensory neurons of the dorsal root ganglia and send axons that synapse in the thalamus.

The neurons contained within the nucleus form a visible bump called the gracile tubercle on the posterior side of the closed medulla at the floor of the fourth ventricle.

The gracile nucleus and fasciculus carry epicritic, kinesthetic, and conscious proprioceptive information from the lower part of the body (below the level of T6 in the spinal cord). The counterpart to the gracile nucleus and fasciculus is the cuneate nucleus and fasciculus, which carries the same type of information, but from the upper body (above T6, excepting the face and ear - the information from the face and ear is carried by the primary sensory trigeminal nucleus).

Decussation of pyramids.

Dissection of brain-stem. Lateral view.

Deep dissection of brain-stem. Lateral view.

Superior terminations of the posterior fasciculi of the medulla spinalis.

Section of the medulla oblongata at about the middle of the olive.

Diagram showing the course of the arcuate fibers.

The formatio reticularis of the medulla oblongata, shown by a transverse section passing through the middle of the olive.

Scheme showing the course of the fibers of the lemniscus; medial lemniscus in blue, lateral in red.

Transverse section passing through the sensory decussation.

Deep dissection of cortex and brain-stem.

The sensory tract.

v • d • e
Brain: rhombencephalon (hindbrain)
Myelencephalon/medulla

anterior/ventral: Arcuate nucleus of medulla • Pyramid (Decussation) • Olivary body • Inferior olivary nucleus • Anterior median fissure • Ventral respiratory group

posterior/dorsal: VII,IX,X: Solitary/tract • XII, X: Dorsal • IX,X,XI: Ambiguus • IX: Inferior salivatory nucleus • Gracile nucleus/Cuneate nucleus/Accessory cuneate nucleus • Area postrema • Posterior median sulcus • Dorsal respiratory group

raphe/reticular: Sensory decussation • Reticular formation (Gigantocellular nucleus, Parvocellular reticular nucleus, Ventral reticular nucleus, Lateral reticular nucleus, Paramedian reticular nucleus) • Raphe nuclei (Obscurus, Magnus, Pallidus)

tracts: Corticospinal tract (Lateral, Anterior) • Inferior cerebellar peduncle • Olivocerebellar tract • Spinocerebellar (Dorsal, Ventral) • Spinothalamic tract • PCML (Posterior external arcuate fibers, Internal arcuate fibers, Medial lemniscus) • Extrapyramidal (Rubrospinal tract, Vestibulospinal tract, Tectospinal tract)
Metencephalon/pons
Metencephalon/cerebellum Vermis • Flocculus • Arbor vitae • Cerebellar tonsil • Inferior medullary velum

Molecular layer (Stellate cell, Basket cell, Parallel fiber) • Purkinje cell layer (Purkinje cell) • Granule cell layer (Golgi cell) • Mossy fibers • Climbing fiber

Deep cerebellar nuclei (Dentate, Emboliform, Globose, Fastigial)
Fourth ventricle apertures (Median, Lateral) • Rhomboid fossa (Vagal trigone, Hypoglossal trigone, Obex, Sulcus limitans, Facial colliculus, Medial eminence) • Lateral recess
Retrieved from "http://en.wikipedia.org/wiki/Gracile_nucleus"
Advanced Search
Included Web Search Engines


Safe Search

close

Top Matching Results

Occasionally Search.com will highlight specialized results that are based on the context of your query. Examples of specialized results include specific links to news, images, or video.

Top Matching Results may highlight information from other Search.com pages, content from the CNET Network of sites, or third party content. The listings are based purely on relevance. Search.com does not receive payment for listings in this section but our partners that provide this data may get paid for listing these products.

Sponsored Links

This section contains paid listings which have been purchased by companies that want to have their sites appear for specific search terms and related content. These listings are administered, sorted and maintained by a third party and are not endorsed by Search.com.

Search Results

Search.com sends your search query to several search engines at one time and integrates the results into one list which has been sorted by relevance using Search.com's proprietary algorithm. You can customize the list of search engines included in your metasearch from the preferences.

The search engines that are used in your metasearch may allow companies to pay to have their Web sites included within the results. To view the Paid Inclusion policy for a specific search engine, please visit their Web site. Search.com does not accept payment or share revenue with any search engine partner for listings in this section.