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 (dĕk′ə-sā′shən, dē′kə-)
1. A crossing in the shape of an X.
2. Anatomy An X-shaped crossing, especially of nerves or bands of nerve fibers, connecting corresponding parts on opposite sides of the brain or spinal cord.


(ˌdi kəˈseɪ ʃən, ˌdɛk ə-)

1. an instance of crossing or the condition of being crossed in the form of an X.
2. a nerve or tract of nerve fibers that crosses from one side of the central nervous system to the other.


the state of being in the form of an X. See also joining.
See also: Form
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.decussation - an intersection or crossing of two tracts in the form of the letter X
anatomical structure, bodily structure, body structure, complex body part, structure - a particular complex anatomical part of a living thing; "he has good bone structure"
chiasma opticum, optic chiasm, optic chiasma - the crossing of the optic nerves from the two eyes at the base of the brain


n. decusación, cruzamiento de estructuras en forma de X;
___ of pyramids___ de las pirámides, cruzamiento de fibras nerviosas de una pirámide a otra en la médula oblongata;
optic ______ óptica, cruzamiento de las fibras del nervio óptico.
References in periodicals archive ?
It has a focal expression at the pyramidal decussation during critical neurodevelopmental stages.
It has been confirmed using adult rats that unilateral damage in the cerebral hemisphere caused during the juvenile period (when corticospinal tract axons are still forming projections in a caudal direction) allows the corticofugal projection fibers that are descending from the sensorimotor area of the cerebral cortex on the undamaged side to form bilateral axonal projections at each level of the thalamus [14]; striatum [15]; superior colliculus, red nuclei, and pontine nuclei in the midbrain [16]; pyramidal decussation [17]; and spinal cord [18].