The anatomy of the nervous system, from the standpoint of development and function . o receives fibersfrom the cerebral cortex. It contains important reflex centers, those in thesuperior colliculus being dominated by visual, those in the inferior colliculusby auditory, impulses. The inferior colliculi or inferior quadrigeminal bodies each contain, in addi-tion to the laminated gray matter of the tectum, a large gray mass, oval intransverse section, and known as the nucleus of the inferior colliculus (Fig. 114). 166 THE NERVOUS SYSTEM The lateral lemniscus has been traced to this nucleus, and w
The anatomy of the nervous system, from the standpoint of development and function . o receives fibersfrom the cerebral cortex. It contains important reflex centers, those in thesuperior colliculus being dominated by visual, those in the inferior colliculusby auditory, impulses. The inferior colliculi or inferior quadrigeminal bodies each contain, in addi-tion to the laminated gray matter of the tectum, a large gray mass, oval intransverse section, and known as the nucleus of the inferior colliculus (Fig. 114). 166 THE NERVOUS SYSTEM The lateral lemniscus has been traced to this nucleus, and while some of thelibers plunge directly into it, others sweep around it to form a capsule, withinwhich it is enclosed. The majority of these fibers ultimately end in this nu-cleus, but some pass beyond it, reach the median plane, and decussate with sim-ilar fibers from the opposite side (Fig. 118). The ramifications of fibers from thelateral lemniscus form an intricate interlacement within the nucleus, andthroughout this network are scattered many nerve-cells of various shapes and. Fig. 118.—Semidiagrammatic section through the inferior colliculus of the mouse: A, Nucleusof inferior colliculus; B, gray matter of the lamina quadrigemina; C, inferior quadrigeminal bra-chium; D, central gray substance; K, decussation of the brachium conjunctivum; a, b, c, d, fibersof the lateral lemnisus. Golgi method. (Cajal.) sizes. On the medial side of this circumscribed nuclear mass we find some ofthe laminated gray matter of the tectum, within which are embedded large mul-tipolar cells with axons directed ventrally in the stratum profundum. Thesepartially encircle the central gray matter and after undergoing a partial decus-sation enter the tectobulbar and tectospinal tracts. The inferior quadrigeminal brachium begins on the lateral side of the nucleusof the inferior colliculus and consists of fibers from the lateral lemniscus which THE 1XTKKNAL STRIXTIKK OF Till; MESENCEPHALON [67 run to a
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectnervoussystem, bookye
