Tectospinal tract
Encyclopedia
In humans, the tectospinal tract (also known as colliculospinal tract) is a nerve pathway which coordinates head and eye movements. It is part of the indirect extrapyramidal tract. Specifically, the tectospinal tract connects the midbrain tectum
and the spinal cord
.
It is responsible for motor impulses that arise from one side of the midbrain to muscles on the opposite side of the body
. 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
, which receives afferents from the visual nuclei (primarily the oculomotor nuclei complex), then projects to the contralateral (decussating ventral to the mesencephalic duct) and ipsilateral portion of the first cervical neuromeres of the spinal cord
, the oculomotor and trochlear nuclei in the midbrain and the abducent nucleus in the caudal portion of the pons.
The tract descends to the cervical spinal cord to terminate in Rexed laminae
VI, VII, and VIII to coordinate head
, neck
, and eye
movements, primarily in response to visual stimuli.
Midbrain tectum
The tectum is a region of the brain, specifically the dorsal part of the mesencephalon . This is contrasted with the tegmentum, which refers to the region ventral to the ventricular system...
and the spinal cord
Spinal cord
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system...
.
It is responsible for motor impulses that arise from one side of the midbrain to muscles on the opposite side of the body
Body
With regard to living things, a body is the physical body of an individual. "Body" often is used in connection with appearance, health issues and death...
. 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
Superior colliculus
The optic tectum or simply tectum is a paired structure that forms a major component of the vertebrate midbrain. In mammals this structure is more commonly called the superior colliculus , but, even in mammals, the adjective tectal is commonly used. The tectum is a layered structure, with a...
, which receives afferents from the visual nuclei (primarily the oculomotor nuclei complex), then projects to the contralateral (decussating ventral to the mesencephalic duct) and ipsilateral portion of the first cervical neuromeres of the spinal cord
Spinal cord
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system...
, the oculomotor and trochlear nuclei in the midbrain and the abducent nucleus in the caudal portion of the pons.
The tract descends to the cervical spinal cord to terminate in Rexed laminae
Rexed laminae
The Rexed laminae comprise a system of ten layers of grey matter , identified in the early 1950s by Bror Rexed to label portions of the spinal cord...
VI, VII, and VIII to coordinate head
Head
In anatomy, the head of an animal is the rostral part that usually comprises the brain, eyes, ears, nose and mouth . Some very simple animals may not have a head, but many bilaterally symmetric forms do....
, neck
Neck
The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney...
, and eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...
movements, primarily in response to visual stimuli.
