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Relating to a commissure.


Relating to a commissure.


(kom'i-shur?) [ commissura]
1. In the central nervous system, an axon tract that crosses the midline (sagittal) plane between two homologous and symmetric structures, e.g., the corpus callosum, which interconnects the right and left cerebral cortices.
2. The meeting of two structures, as the lips, eyelids, or labia, across the midline (sagittal) plane. commissural (kom?i-shur'al), adjective

anterior commissure

A symmetric axon tract running transversely through the lamina terminalis and connecting the right and left temporal cortices.

commissure of the fornix

Hippocampal commissure.

Gudden inferior commissure

See: Gudden inferior commissure

habenular commissure

A group of decussating axons of the stria medullaris. The stria medullaris contains axons projecting to the habenula from the septal nuclei, the preoptic hypothalamus, and the anterior thalamic nuclei; those stria medullaris axons that project to the contralateral habenula cross the midline plane via the habenular commissure.

hippocampal commissure

A thin sheet of axons from the fornix that cross the midline plane under the posterior sector of the corpus callosum and interconnect homologous fields of the right and left hippocampi.
Synonym: commissure of fornix

Meynert commissure

See: Meynert commissure

palpebral commissure

The union of the upper and lower eyelids at each end of the palpebral fissure.

posterior commissure

An axon tract running transversely through the gray matter that forms the roof of the cerebral aqueduct in the midbrain. This tract contains commissural axons interconnecting the right and left pretectal areas; it also contains decussating axons from each pretectal area to the contralateral Edinger-Westphal nucleus.

posterior commissure of spinal cord

The gray commissure connecting the halves of the spinal cord, lying behind the central canal.

tectal commissure

A symmetric axon tract running transversely through the ventral tectum of the midbrain and interconnecting the right and left superior colliculi.
References in periodicals archive ?
Commissural chordae inserted to the margins of commissural cusps in 58 heart specimens and in 2 specimens' absence of commissural chordae (Figure 4).
It differs from Acrotreta curvata Kloucek, 1919 from the Lower Ordovician, Trenice Formation of Bohemia revised by Mergl (2002) in having a ventral valve as a low cone with not exceeding commissural shell length in height, an almost flat sagittal profile of the dorsal valve, a significantly lower and shorter apical process, weakly impressed ventral mantle canals and dorsal cardinal and central muscle scars.
Commissural process of intraarticular and extraarticular character was revealed in all patients.
The commissural connections of the monkey hippocampal formation.
The innervation of the DB in Helix aspersa and Theba pisana originates from peptidergic neurons of the cerebral ganglia (cerebral green cells, CGC) via commissural nerves.
Distribution and properties of commissural and other neurons in cat sensorimotor cortex.
Multiform tumors are glial tumors that disseminate through white matter tracts (via commissural, callosal body, internal capsule, massa intermedia), or cerebrospinal fluid (including the subarachnoid spaces and ventricular system), or from metastatic tumor satellite lesions or brain edema.
Eighteen fetuses demonstrated brain malformations, such as commissural anomalies (three cases), holoprosencephaly (one), posterior fossa pathologies (four), tuberous sclerosis (three), cortical malformations (three), and a combination of anomalies.
Quantitative analysis of myelinated axons of commissural fibers in the rat brain.
Spinal-cord commissural neurons, which relay pain and temperature sensations to the brain, have been a model system for understanding the principles of growth-cone guidance.
Thus, the cortex, basal ganglia, cerebellum, and the thalamus have highly specific afferent, efferent, interneuronal, and commissural connections.
This study present a right atrioventricular valve bicuspid, whit a clearly septal component with one valvule, and a mural component with a wide anterior valvule and a small anteroseptal commissural cusp.