cerebral peduncle(redirected from pedunculus cerebri)
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1. a stemlike connecting part.
2. a collection of nerve fibers connecting between different regions in the central nervous system.
3. the stalk by which a nonsessile tumor is attached to normal tissue. adj., adj pedun´cular.
cerebellar p's three sets of paired bundles (superior, middle, and inferior) connecting the cerebellum to the midbrain, pons, and medulla oblongata, respectively.
cerebral peduncle the anterior half of the midbrain, divisible into a posterior part (tegmentum) and an anterior part (crus cerebri), which are separated by the substantia nigra.
inferior cerebellar peduncle a large bundle of nerve fibers serving to connect the medulla oblongata and spinal cord with the cerebellum (especially the archicerebellum and paleocerebellum); it courses along the lateral border of the fourth ventricle and turns dorsally into the cerebellum. Formerly called caudal cerebellar peduncle.
middle cerebellar peduncle a large bundle of projection fibers originating in the contralateral pontine nuclei and entering the cerebellum, conveying impulses from the cerebral cortex to the neocerebellum.
pineal peduncle habenula (def. 2).
superior cerebellar peduncle a large bundle of projection fibers arising chiefly in the dentate nucleus of each cerebellar hemisphere (neocerebellum) and ascending to decussate in the mesencephalon; its fibers end mostly in the red nucleus and thalamus. Spinocerebellar fibers to the paleocerebellum lie adjacent to each peduncle. Formerly called rostral cerebellar peduncle.
p's of thalamus the four two-way radiations of thalamocortical fibers that connect the dorsal thalamus with many parts of the cerebral cortex, which together form a major portion of the internal capsule and the corona radiata.
originally denoting either of the two halves of the midbrain (a relatively narrow "neck" connecting the forebrain to the hindbrain); this term has been variably used to designate only those large bundles of corticofugal fibers forming the crus cerebri or to designate the crus cerebri plus the midbrain tegmentum; this latter, more inclusive, usage (crus cerebri and midbrain tegmentum) is preferred by some; the substantia nigra, while a part of the base of the peduncle (basis pedunculi), is considered a structure separating the midbrain tegmentum from the crus cerebri.
See also: crus cerebri.
See also: crus cerebri.
Synonym(s): pedunculus cerebri [TA]
Etymology: L, cerebrum, brain, pes, foot
a pair of ovoid masses of nerve fibers at the upper border of the pons that disappear into the left and right hemispheres of the cerebrum. It includes corticopontine and pyramidal-tract fibers and helps constitute the central portion of the midbrain.
ce·re·bral pe·dun·cle(ser'ĕ-brăl pĕ-dŭngk'ĕl) [TA]
pertaining to the cerebrum. See also brain.
arterial blood supply reaches the anterior, middle and posterior cerebral arteries via the circle of Willis, in some species originating directly from the internal carotid and basilar arteries, in others via an interposed rete mirabile. See also blood-brain barrier, blood-CSF barrier, cerebrospinal fluid.
contusion of the brain following a head injury. See also cerebral contusion.
cerebral cortical dysplasia
encompasses a range of disorders including neuronal heterotopia, microgyria, ulegyria, lissencephaly, pachygyria.
cerebral diencephalic syndrome
the clinical signs associated with lesions of the cerebral cortex and diencephalon. They include behavioral or mental change, abnormal movements such as circling and head pressing, deficits in contralateral postural responses and sometimes visual impairment.
cerebral dura mater
the membranous cover around the brain. Endosteal and meningeal layers are separated only by the cranial venous sinuses. Continuous with the spinal cord dura and the sheaths of the spinal nerves. Has three internal folds which separate sections of the brain. See falx cerebri, tentorium cerebelli, sella turcica.
cerebral edema, cytotoxic
caused by neurotoxins, this edema is intracellular.
cerebral edema, generalized
when all cerebral tissues are affected as in disturbances which create marked differences from normal of sodium and potassium ion concentration in tissues.
cerebral edema, interstitial
edema of the central white matter as in hydrocephalus affecting the brain and hydromyelia affecting the spinal cord.
cerebral edema, vasogenic
when the edema is intercellular and due usually to damage to the vascular endothelium.
the congestion of the cerebral vessels causing a pink coloration; of infections by Babesia bovis and B. bigemina it is the former in which the cerebral flush occurs.
convolutions on the surface of the cerebrum.
symmetrical right and left halves of the cerebrum divided by the longitudinal fissure.
see cerebral peduncle.
cerebral pia mater
thin connective tissue membrane that lies closely against the cerebral surface and carries blood vessels into the tissues of the brain.
cerebral piriform lobe
on the floor of the brain medial to the lateral olfactory tract.
frontal (rostral) and occipital (caudal) poles of the cerebrum.
cerebral substantia nigra
occupies the interior of the cerebral peduncles.
characterized by abnormal mental state, abnormal movements such as pacing or head pressing, visual impairment and seizures.
infection with Theileria parva or aberrant forms of T. taurotragi originating from the eland. Called also turning sickness.
cerebral vascular accident (CVA)
a disorder of the blood vessels serving the cerebrum, resulting from an impaired blood supply to parts of the brain. Called stroke in humans.
a stemlike connecting part, especially: (1) a collection of nerve fibers coursing between different regions in the central nervous system, or (2) the stalk by which a nonsessile tumor is attached to normal tissue.
three pairs of thick, white fiber trunks that arise from the midbrain, pons and medulla and pass into the cerebellum.
the ventral half of the midbrain, divisible into a dorsal part (tegmentum) and a ventral part (crus cerebri), which are separated by the substantia nigra.
a disease of marine fish caused by the flexibacter Cytophaga psychrophila.
caudal continuation of the olfactory bulb of the brain.
see habenula (2).