| capsula interna | <anatomy, neurology> A massive layer (8 to 10 mm thick) of white matter separating the caudate nucleus and thalamus (medial) from the more laterally situated lentiform nucleus (globus pallidus and putamen). It consists of 1) fibres ascending from the thalamus to the cerebral cortex that compose, among others, the visual, auditory, and somatic sensory radiations, and 2) fibres descending from the cerebral cortex to the thalamus, subthalamic region, midbrain, hindbrain, and spinal cord. The internal capsule is the major route by which the cerebral cortex is connected with the brainstem and spinal cord. Laterally and superiorly it is continuous with the corona radiata which forms a major part of the cerebral hemisphere's white matter; caudally and medially it continues, much reduced in size, as the crus cerebri which contains, among others, the pyramidal tract. On horizontal section it appears in the form of a V opening out laterally; the V's obtuse angle is called genu (knee). Its anterior and posterior limbs, respectively, the crus anterior and crus posterior. Synonym: capsula interna. (05 Mar 2000) |
|---|---|
| capsula lentis | The capsule enclosing the lens of the eye. Synonym: capsula lentis, crystalline capsule, lenticular capsule, phacocyst. (05 Mar 2000) |
| capsula lienis | The fibrous capsule of the spleen, containing collagen, elastic fibres, and smooth muscle. Synonym: tunica fibrosa splenis, tunica fibrosa lienis, capsula lienis, tunica propria lienis. (05 Mar 2000) |
| capsula vasculosa lentis | In the embryo, the vascular mesenchymal capsule that invests the lens of the eye; the vessels of the dorsal part of the capsule are branches of the hyaloid artery; those of the ventral part are derived from the anterior ciliary arteries; normally all the vessels are atrophied by the end of the eighth month of intrauterine life. (05 Mar 2000) |
| accessory olivary nuclei | See: dorsal accessory olivary nucleus, medial accessory olivary nucleus. (05 Mar 2000) |
| anterior nuclei of thalamus | Collective term for three groups of nerve cells which together form the anterior thalamic tubercle: the anteroventral nuclei, a relatively large nucleus; the anteromedial nuclei; and the anterodorsal nuclei, a small (but large-celled) nucleus. The nuclei receive the mamillothalamic tract from the mamillary body, and additional afferents by way of the fornix; they project collectively to the cortex of the cingulate and parahippocampal gyrus. Synonym: nuclei anteriores thalami. (05 Mar 2000) |
| arcuate nuclei | A variable assembly of small cell groups, probably outlying components of the pontine nuclei, on the ventral and medial aspects of the pyramid in the medulla oblongata. Synonym: nuclei arcuati. (05 Mar 2000) |
| autonomic nuclei | Nuclei located in the spinal cord (T1-L2, S2-S4) and in the brainstem (Edinger-Westphal nucleus, superior and inferior salivatory nuclei, dorsal vagal nucleus and parts of the ambiguus nucleus) from which general visceral efferent preganglionic fibres arise; may be sympathetic (T1-L2) or parasympathetic (craniosacral); hypothalamic nuclei/areas function in concert with autonomic nuclei. (05 Mar 2000) |
| basal nuclei | Nucleus of the cerebral hemisphere that originally included the caudate and lenticular nuclei, the claustrum and the amygdaloid body (complex); functionally the term basal nuclei now specifies the caudate and lenticular nuclei and adjacent cell groups having important connections therewith (subthalamic nucleus; substantia nigra, partes compacta and reticulata); amygdaloid complex now known to be part of the limbic system. Synonym: nuclei basales. (05 Mar 2000) |
| branchiomotor nuclei | Collective term for those motoneuronal nuclei of the brainstem (n. Ambiguus, facial motor nucleus, motor nucleus of the trigeminus) that develop from the branchiomotor column of the embryo and innervate striated muscle fibres (muscles of mastication, facial musculature, pharynx and vocal cord muscles) developed from the mesenchyme of the branchial arches. Synonym: special visceral efferent nuclei, special visceral motor nuclei. (05 Mar 2000) |
| caput nuclei caudati | The head or anterior extremity of the caudate nucleus projecting into the anterior horn of the lateral ventricle. Synonym: caput nuclei caudati, anterior extremity of caudate nucleus. (05 Mar 2000) |
| rami caudae nuclei caudati | Branches to the tail of the caudate nucleus. Branches from either the anterior choroid or the posterior communicating artery, or both, to supply the tail of the caudate nucleus, a branch from the middle cerebral artery to the tail of the caudate nucleus. (05 Mar 2000) |
| venae nuclei caudati | Small veins from the caudate nucleus draining into the superior thalamostriate vein. Synonym: veins of caudate nucleus. (05 Mar 2000) |
| parabrachial nuclei | The cell groups flanking the brachium conjunctivum at levels immediately caudal to the inferior colliculus; they serve as way-stations in the pathways ascending from the nucleus of solitary tract to the thalamus and hypothalamus, and receive afferent fibres from the hypothalamus and amygdaloid body. Synonym: nuclei parabrachiales. (05 Mar 2000) |
| raphe nuclei | Collections of small neurons centrally scattered among many fibres from the level of the trochlear nucleus in the midbrain to the hypoglossal area in the medulla oblongata. (12 Dec 1998) |