In humans, the tectospinal tract (or colliculospinal tract) is a

nerve tract A nerve tract is a bundle of nerve fibers (axons) connecting nuclei of the central nervous system. In the peripheral nervous system this is known as a nerve, and has associated connective tissue. The main nerve tracts in the central nervous syste ...

that coordinates head and eye movements. This tract is part of the

extrapyramidal system In anatomy, the extrapyramidal system is a part of the motor system network causing involuntary actions. The system is called ''extrapyramidal'' to distinguish it from the tracts of the motor cortex that reach their targets by traveling through t ...

and connects the midbrain tectum, and cervical regions of the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...

. It is responsible for motor impulses that arise from one side of the midbrain to muscles on the opposite side of the body (contralateral). The function of the tectospinal tract is to mediate reflex postural movements of the head in response to visual and auditory stimuli. The portion of the midbrain from where this tract originates is the

superior colliculus In neuroanatomy, the superior colliculus () is a structure lying on the roof of the mammalian midbrain. In non-mammalian vertebrates, the homologous structure is known as the optic tectum, or optic lobe. The adjective form ''tectal'' is commonly ...

, which receives afferents from the visual nuclei (primarily the oculomotor nuclei complex), then projects to the

contralateral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

(decussating dorsal to the mesencephalic duct) and ipsilateral portion of the first cervical neuromeres of the

, the oculomotor and trochlear nuclei in the midbrain and the abducens nucleus in the caudal portion of the pons. The tract descends to the

cervical spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...

to terminate in

Rexed laminae The Rexed laminae comprise a system of ten layers of grey matter (I–X), identified in the early 1950s by Bror Rexed to label portions of the grey columns of the spinal cord. Similar to Brodmann areas, they are defined by their cellular struct ...

VI, VII, and VIII to coordinate

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may ...

neck The neck is the part of the body on many vertebrates that connects the head with the torso. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In ...

, and eye movements, primarily in response to visual stimuli.

References

External links

Diagram at etsu.edu

* {{Authority control Spinal cord tracts Motor system

See also

References

External links