The descending tracts of the spinal cord are situated only in the anterior and lateral funiculi of the white matter. They originate from neurons located in various regions of the cerebral cortex and brainstem.

The pyramidal tracts descend directly from the cerebral cortex to the spinal cord, while the extrapyramidal tracts originate in the brainstem.

Descending tracts of anterior funiculus

The anterior funiculus contains the following descending pathways:

Tectospinal tract - extrapyramidal tract that connects the superior colliculus of the midbrain with the spinal cord; it is located only in the upper cervical spinal segments; provides reflector head and eye movements as a protective response to unexpected visual or auditory stimuli;
Anterior corticospinal tract - pyramidal tract that links the motor cortex of the cerebrum with the spinal cord; it is formed by the corticospinal tract fibers that do not cross to the opposite side in the caudal medulla oblongata; responsible for postural and gross movements of the trunk and proximal muscles;
Medial (pontine) reticulospinal tract - one of the extrapyramidal tracts; connects the pons (pontine reticular nuclei) with the spinal cord; it regulates and enables postural control and proximal stability, inhibits limb flexors and activates extensors;
Lateral vestibulospinal tract and medial vestibulospinal tract - extrapyramidal tracts that link the medulla oblongata and pons with the spinal cord; they coordinate reflexes linked to balance, therefore, they participate in maintaining posture and balance.

Descending tracts of lateral funiculus

Descending pathways included in the lateral funiculus are as follows:

Lateral corticospinal tract - one of the pyramidal tracts; connects the motor cortex with the spinal cord, and it is formed by the descending corticospinal fibers that cross in the medulla oblongata; responsible for voluntary movements of contralateral (opposite) muscles of the limbs;
Rubrospinal tract - extrapyramidal tract that links the midbrain (red nucleus) with the spinal cord; it controls muscle activity and tone of the upper limb flexors;
Lateral (medullary) reticulospinal tract - extrapyramidal tract that connects the medulla oblongata (medullary reticular formation) with the spinal cord; it regulates and enables postural control and proximal stability, activates the flexors of the limbs and inhibits extensors.

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Descending tracts of spinal cord