Decussation is a term that is used in several different disciplines to identify the incidence of two or more elements crossing. The term is used when referred to several different biological events as well as in business and religion. In all instances, a decussate is the joining of at least two elements at a central point.
A brain decussation is a phenomenon in which the nerve fibers found in one lateral portion of the organ cross another. The status known as pyramidal decussation has to do with the passage of motor fibers from the brain to medulla spinalis and medulla oblongata. The fibers tend to leave the brain is bunches or bundles and cross in the anterior median fissure area of the medulla oblongata.
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Nerve decussation is a term that often refers to the crossing fibers within one eye. As in the case of trochlear nerves, there is a crossing of the nerve fibers as they leave the velium. The phenomenon has been observed with humans as well as with other mammals, fish, and reptiles.
Decussation is also a term that is utilized in the field of dentistry. In this application, the term refers to the pathways of the individual rods that are an integral part of tooth enamel. As those rods extend from the enamel-dentine junction within the inner layer to the outer layer that resides on the surface of the tooth, some are likely to cross. When a cross pattern is noted, it is said that decussates exist within the enamel.
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Decussating is also a phenomenon that is found in the science of botany. When looking at the arrangement of leaves on the stem of a plant, any pattern in which two or more successive pairs of leaves are perpendicular to one another can right be referred to as a decussate. Along with such possible arrangements as the spiral, alternating or the whorl, a leaf decussate is a relatively common arrangement.
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With matters of religion, decussates have to do with the point at which specific points of doctrine intersect. The point at which the concepts of faith and works bisect within some Christian traditions could rightly be referred to as a point of decussation. At that juncture, the two concepts become joined and are seen as two parts of one whole rather than separate ideologies or beliefs.
While used rarely, decussating can also refer to a business strategy in which there is an attempt to solidify a position by crossing two opposing forces. Within this strategy, the opposing forces begin to engage one another, rather than focusing their attention on the third party. This leaves the third party free to covertly move forward with his or her plans without any direct opposition, since the other parties are now crossed with each other.