medial longitudinal fasciculus
Also found in: Dictionary, Thesaurus, Financial, Acronyms, Encyclopedia, Wikipedia.
Related to medial longitudinal fasciculus: Medial lemniscus, central tegmental tract, Tectospinal tract
me·di·al lon·gi·tu·di·nal fas·cic·u·lus[TA]
a longitudinal bundle of fibers extending from the upper border of the mesencephalon primarily into the cervical segments of the spinal cord, located close to the midline and anterior to the central gray matter; it is composed largely of fibers from the vestibular nuclei ascending to the motor neurons innervating the external eye muscles (abducens, trochlear, and oculomotor nuclei), and descending to spinal cord segments innervating the musculature of the neck.
me·di·al lon·gi·tu·di·nal fas·ci·cu·lus(MLF) (mē'dē-ăl lon'ji-tū'di-nal fă-sik'kyū-lŭs) [TA]
Pathway in the brainstem that connects the vestibular system with the cranial nerves that serve the eye muscles (e.g., CNs III, IV, VI).
Collier,James S., English physician, 1870-1935.
Collier sign - unilateral or bilateral lid retraction due to midbrain lesion. Synonym(s): Collier tucked lid sign
Collier tract - a longitudinal bundle of fibers extending from the upper border of the mesencephalon into the cervical segments of the spinal cord. Synonym(s): medial longitudinal fasciculus
Collier tucked lid sign - Synonym(s): Collier sign
fasciculus, medial longitudinal
One of a pair of nerve fibres, one on each side of the midline and extending from the upper midbrain to the cervical spinal cord. It is composed largely of ascending fibres from the vestibular nuclei ascending to the motor nuclei (third, fourth and sixth) and innervating the extraocular muscles; and to a lesser extent of descending fibres from the medial vestibular nuclei, the reticular formation, the superior colliculi and nucleus of Cajal innervating the musculature of the neck. Syn. medial longitudinal bundle; posterior longitudinal bundle.