Descending Spinal Tracts and Corticospinal Overview

A descending motor pathway originating in the red nucleus of the midbrain, playing a role in controlling limb flexor muscle tone.

A descending motor pathway originating in the superior colliculus of the midbrain, mediating reflex movements in response to visual stimuli.

A descending motor pathway originating in the vestibular nuclei, situated in the pons and medulla, responsible for maintaining balance and posture.

This tract descends ipsilaterally in the ventral funiculus and exerts powerful excitatory effects on extensor motor neurons.

A motor pathway connecting the motor cortex to the spinal cord, responsible for voluntary movement.

A condition characterized by spastic paraparesis (weakness in the legs), hyperreflexia (increased reflexes), and extensor plantar responses.

The red nucleus of the midbrain receives input from both the motor cortex and the cerebellum.

The superior colliculus of the midbrain receives visual input.

A lesion that affects the spinal cord at a specific level, leading to disruptions in nerve function.

Descending tracts of the spinal cord that originate from the cerebral cortex and brainstem, responsible for controlling movement, muscle tone, spinal reflexes, autonomic functions, and modulating sensory transmission.

Damage to the spinal cord at a specific level, causing loss of function in that segment.

Tracts that primarily control voluntary, precise, and skilled movements, especially those of the limbs, often referred to as 'fractionated' movements.

Large nerve cells found in the precentral gyrus or primary motor cortex, responsible for initiating voluntary movements and contributing to the largest-diameter corticospinal axons.

Interruption of nerve pathways that carry signals up and down the spinal cord.

A clinical syndrome caused by damage to specific parts of the spinal cord, leading to unique symptoms.

Bundles of nerve fibers that travel from the cerebral cortex to the spinal cord, passing through subcortical structures, the midbrain, pons, and medulla.

A syndrome characterized by weakness, muscle wasting, and decreased reflexes in the lower limbs, as well as sensory loss below the lesion.

The crossing over of nerve fibers from one side of the brain to the other side of the spinal cord, ensuring control of the opposite side of the body.

A condition with ipsilateral (same side) loss of proprioception and upper motor neuron signs, and contralateral (opposite side) loss of pain and temperature sensation.

A syndrome resulting in weakness, wasting, and decreased reflexes in the upper limbs, as well as spastic paraparesis and sensory loss below the lesion.

The ventral corticospinal tract, responsible for controlling movement of the contralateral limbs, and located in the ventral part of the spinal white matter.

A syndrome causing spastic tetraplegia, hyperreflexia, and sensory loss below the lesion.

An inherited degenerative disorder affecting the legs, leading to weakness and stiffness, causing difficulty with walking.

A descending pathway from the vestibular nuclei that primarily controls the extensor muscles involved in maintaining posture.

A bundle of nerve fibers that connects the vestibular nuclei with nuclei controlling eye muscles, crucial for coordinating head and eye movements.

Descending pathways originating from the reticular formation of the brainstem, influencing voluntary movement, reflexes, and muscle tone.

Tracts that facilitate voluntary movement, control reflex activities, and regulate muscle tone, originating from the pons and medulla.