The upper part of the posterior district of the

medulla oblongata The medulla oblongata or simply medulla is a long stem-like structure which makes up the lower part of the brainstem. It is anterior and partially inferior to the cerebellum. It is a cone-shaped neuronal mass responsible for autonomic (involun ...

is occupied by the inferior cerebellar peduncle, a thick rope-like strand situated between the lower part of the

fourth ventricle The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. These cavities, known collectively as the ventricular system, consist of the left and right lateral ventricles, the third ventricle, and the fourth ve ...

and the roots of the

glossopharyngeal The glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper Medulla oblongata, medulla, just anterior (closer to the nose) to t ...

and

vagus nerve The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and right ...

s. Each cerebellar inferior peduncle connects the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...

and medulla oblongata with the

cerebellum The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebel ...

, and comprises the

juxtarestiform body The juxtarestiform body is a subdivision of the inferior cerebellar peduncle, which comprises both the juxtarestiform and restiform bodies. Function The juxtarestiform body carries both afferent and efferent fibers connecting the vestibular nucle ...

and restiform body. Important fibers running through the inferior cerebellar peduncle include the

dorsal spinocerebellar tract The spinocerebellar tract is a nerve tract originating in the spinal cord and terminating in the same side (ipsilateral) of the cerebellum. Origins of proprioceptive information Proprioceptive information is obtained by Golgi tendon organs and m ...

and axons from the

inferior olivary nucleus The inferior olivary nucleus (ION), is a structure found in the medulla oblongata underneath the superior olivary nucleus.Gado, Thomas A. Woolsey; Joseph Hanaway; Mokhtar H. (2003). The brain atlas a visual guide to the human central nervous syste ...

, among others.

Function

The inferior cerebellar peduncle carries many types of input and output fibers that are mainly concerned with integrating

proprioceptive Proprioception ( ), also referred to as kinaesthesia (or kinesthesia), is the sense of self-movement, force, and body position. It is sometimes described as the "sixth sense". Proprioception is mediated by proprioceptors, mechanosensory neurons ...

sensory input with motor vestibular functions such as

balance Balance or balancing may refer to: Common meanings * Balance (ability) in biomechanics * Balance (accounting) * Balance or weighing scale * Balance as in equality or equilibrium Arts and entertainment Film * ''Balance'' (1983 film), a Bulgaria ...

and

posture Posture or posturing may refer to: Medicine * Human position ** Abnormal posturing, in neurotrauma ** Spinal posture ** List of human positions * Posturography Posturography is the technique used to quantify postural control in upright stance in ...

maintenance. It consists of the following fiber tracts entering cerebellum: *

Posterior spinocerebellar tract The spinocerebellar tract is a nerve tract originating in the spinal cord and terminating in the same side (ipsilateral) of the cerebellum. Origins of proprioceptive information Proprioceptive information is obtained by Golgi tendon organs and ...

: unconscious

information from the lower part of trunk and lower limb. This tract originates at the ipsilateral

Clarke's nucleus The posterior thoracic nucleus, (Clarke's column, column of Clarke, dorsal nucleus, nucleus dorsalis of Clarke) is a group of interneurons found in the medial part of lamina VII, also known as the intermediate zone, of the spinal cord. It is mainl ...

(T1-L1) and travels upward to reach the inferior cerebellar peduncle and synapses within the

spinocerebellum The anatomy of the cerebellum can be viewed at three levels. At the level of gross anatomy, the cerebellum consists of a tightly folded and crumpled layer of cortex, with white matter underneath, several deep nuclei embedded in the white matte ...

(also known as the paleocerebellum). *

Cuneocerebellar tract The spinocerebellar tract is a nerve tract originating in the spinal cord and terminating in the same side (ipsilateral) of the cerebellum. Origins of proprioceptive information Proprioceptive information is obtained by Golgi tendon organs and ...

: unconscious proprioceptive information from the upper limb and neck. This tract originates at the ipsilateral accessory cuneate nucleus and travels through the inferior cerebellar peduncle to reach the spinocerebellum part of the cerebellum. * Trigeminocerebellar tract: unconscious proprioceptive information from the face. *

Olivocerebellar tract The olivocerebellar tract, also known as olivocerebellar fibers, are neural fibers which originate at the olivary nucleus and pass out through the hilum and decussate with those from the opposite olive in the raphe nucleus, then as internal arcua ...

: "error signal" in movement originates from the cerebral cortex and spinal cord. This tract originates at contralateral inferior olivary nucleus and enters the cerebellum as a

climbing fiber Climbing fibers are the name given to a series of neuronal projections from the inferior olivary nucleus located in the medulla oblongata. These axons pass through the pons and enter the cerebellum via the inferior cerebellar peduncle whe ...

. *

Vestibulocerebellar tract The vestibulocerebellar tract is a tract in the pontine tegmentum which connects the vestibular nerve and the cerebellar cortex The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually ...

: vestibular information projects onto the

vestibulocerebellum The anatomy of the cerebellum can be viewed at three levels. At the level of gross anatomy, the cerebellum consists of a tightly folded and crumpled layer of cortex, with white matter underneath, several deep nuclei embedded in the white matte ...

(also known as the archicerebellum). This peduncle also carries information leaving cerebellum: from the

Purkinje cells Purkinje cells, or Purkinje neurons, are a class of GABAergic inhibitory neurons located in the cerebellum. They are named after their discoverer, Czech anatomist Jan Evangelista Purkyně, who characterized the cells in 1839. Structure The ...

to the vestibular nuclei in the dorsal

brainstem The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is cont ...

located at the junction between the

pons The pons (from Latin , "bridge") is part of the brainstem that in humans and other bipeds lies inferior to the midbrain, superior to the medulla oblongata and anterior to the cerebellum. The pons is also called the pons Varolii ("bridge of Va ...

and

Additional images

File:Gray691.png, Dissection of brain-stem. Dorsal view. File:Gray699.png, Diagram showing the course of the arcuate fibers. File:Lower pons horizontal KB.svg, Cross section of lower pons showing part of the inferior cerebellar peduncle (#8) labeled at the upper left. File:Slide2SEER.JPG, Cerebellum. Inferior surface.

References

External links

* * * {{DEFAULTSORT:Inferior Cerebellar Peduncle Brainstem Cerebellar connections

Function

See also

Additional images

References

External links