Fiber Connections of the Richly Myelinated Hypothalamus

 Fiber Connections of the Richly Myelinated Hypothalamus

Primarily afferent pathways of the mamillary body (BC10) are the fornix (BC8), the fibers of which terminate primarily in the mamillary body, and the peduncle of themamillary body (C13) from the tegmental nuclei of the midbrain, which is thought to contain also gustatory fibers, vestibular fibers, and fibers from the medial lemniscus.


Primarily efferent pathways are repre-sented by the mamillothalamic fasciculus (Vicq d'Azyr’s bundle) (C14) which ascends to the anterior nucleus of thethalamus (C15). The projection of the ante-rior nucleus to the cingulate gyrus estab-lishes a connection between the hypo-thalamus and the limbic association cortex.The mamillotegmental fasciculus (C16) termi-nates in the tegmental nuclei of the mid-brain. All pathways contain a high propor-tion of peptidergic fibers.

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