What is a fasciculus lesion?

A lesion of the MLF produces slowed or absent adduction of the ipsilateral eye upon contralateral gaze, usually associated with involuntary jerky eye movements (nystagmus) of the abducting eye, a syndrome called internuclear ophthalmoplegia.

What does the medial longitudinal fasciculus connect?

The medial longitudinal fasciculus links the three main nerves which control eye movements, i.e. the oculomotor, trochlear and the abducent nerves, as well as the vestibulocochlear nerve. The purpose of the medial longitudinal fasciculus is to integrate movement of the eyes and head movements.

Where is the medial longitudinal fasciculus located?

The medial longitudinal fasciculus (MLF) is organized as a pair of white matter fiber tracts that extend through the brainstem and lie near the midline just ventral to the fourth ventricle (in the medulla and pons) and cerebral aqueduct (in the midbrain).

Where is the MLF found?

The MLF are a group of fiber tracts located in the paramedian area of the midbrain and pons. They control horizontal eye movements by interconnecting oculomotor and abducens nuclei in the brain stem.

What’s a fasciculus?

Medical Definition of fasciculus : a slender bundle of fibers: a : a bundle of skeletal muscle cells bound together by fasciae and forming one of the constituent elements of a muscle.

What is the inferior longitudinal fasciculus?

The inferior longitudinal fasciculus (ILF) is a long-range, associative white matter pathway that connects the occipital and temporal-occipital areas of the brain to the anterior temporal areas.

What is the function of the longitudinal fasciculus?

The superior longitudinal fasciculus (SLF) is an extensive white-matter tract that mainly communicates between frontal and parietal lobes, and provides partial communication with the temporal lobe. It interconnects nearly all cortical areas of the lateral cerebral hemisphere.

What is MLF neurology?

The medial longitudinal fasciculus (MLF) is a myelinated composite fibre tract found in the brainstem. The MLF primarily serves to coordinate the conjugate movement of the eyes and associated head and neck movements.

What is internuclear ophthalmoplegia?

Internuclear ophthalmoplegia (INO) is a disorder of eye movements caused by a lesion in an area of the brain called the medial longitudinal fasciculus (MLF). The most common causes of INO are multiple sclerosis and brainstem infarction.

What is the difference between fasciculus and funiculus?

A nerve fascicle, or fasciculus is a bundle of funiculi. A funiculus is a bundle of axons. A nerve fascicle refers to nerves in the peripheral nervous system; in the central nervous system this is known as a nerve tract.

What is the arcuate fasciculus responsible for?

The arcuate fasciculus is a bundle of axons that connects the temporal cortex and inferior parietal cortex to locations in the frontal lobe. One of the key roles of the arcuate fasciculus is connecting Broca’s and Wernicke’s areas, which are involved in producing and understanding language.

What is the inferior longitudinal muscle?

The inferior longitudinal muscle of the tongue is one of the four intrinsic muscles of the tongue, which alter the shape of the tongue mass, being entirely confined to the tongue without any extraglossal attachment (cf. extrinsic muscles of the tongue).