Neuronal Pathway of Slow Pain

Study Notes

Neuronal Pathways for Pain and Touch

Slow Pain Pathway: located in the lateral funiculus of the spinal cord, transmits diffuse, unbounded pain, and is part of the Ascending Reticular Activating System (ARAS) which regulates consciousness and modulates CNS activity.
First Neuron: pseudounipolar cells of the spinal ganglion, with dendrites in spinal nerves and axons terminating in the posterior horns of the spinal cord.
Second Neuron: ispilateral nucleus proprius of the posterior horn, with most axons running ipsilaterally and a small part contralaterally, accompanying the lateral spinothalamic tract in the spinal lemniscus and terminating in the nuclei of the reticular formation.

Spino-Reticular Tract

Function: transmits touch and painful stimuli to the reticular formation.
Connections: 2-neuron pathway, with the first neuron being pseudounipolar cells of the spinal ganglion, and the second neuron being ispilateral nucleus proprius of the posterior horn.

Spino-Tectal Tract

Location: in the lateral funiculus of the spinal cord, rudimentary in humans.
Function: transmits touch and painful stimuli to the tectum of the midbrain, serving for coordination of eyes, head, and neck movements towards touch and painful stimuli.
Connections: 2-neuron pathway, with the first neuron being pseudounipolar cells of the spinal ganglion, and the second neuron being ispilateral nucleus proprius of the posterior horn, with axons crossing over in the spinal lemniscus to the superior colliculus of the tectum.

Description

This quiz covers the neuronal pathway responsible for transmitting diffuse, unbounded pain, part of the ARAS that keeps consciousness awake and modulates CNS activity. It involves two neurons, starting from pseudounipolar cells in spinal ganglion and ending in the posterior horn of the spinal cord.