SPINOTHALAMIC AND CORTICOSPINAL TRACT; COMPARISON

BAYETA, JENNICA MAYE ZARA

BSN III-I

COMPARISON

SPINOTHALAMIC TRACT Sensory pathway

Ascending pathway

Destination; thalamus

*this means that spinothalamic tract transmit information to the thalamus

CORTICOSPINAL TRACT Motor pathway

Descending pathway

Destination; spinal cord

*corticospinal tract conducts impulses from the brain to the spinal cord

COMPARISONSPINOTHALAMIC TRACT

Responsible for conduction of pain, temperature, proprioception, fine touch, crude touch, itch, and vibratory sense

Decussates at the level of spinal cord

CORTICOSPINAL TRACT

Responsible for discrete voluntary movements; precise movement of the fingers and toes

Decussates at the level of medulla oblongata

DECUSSATION

...the cross-over of the tract from one side to the other. This explains why there are instances that the left side of the body is controlled by the right brain hemisphere.

ADDITIONAL KNOWLEDGE :)

Spinothalamic tract and corticospinal tract differs in the location where each order of neuron ends.

SPINOTHALAMIC TRACT

Flow of arrangement...

1st order neuron Arise from sensory receptors of the body The fibers enter the white mater and ends at the substantia

gelatinosa, tip of posterior gray horn

2nd order neuron The fibers of 1st order neuron synapse with the 2nd order neuron at

the substantia gelatinosa These fibers then cross to the opposite side

*Pain and temperature fibers enters the lateral spinothalamic tract

SPINOTHALAMIC TRACT

*Light touch and pressure fibers enters the anterior spinothalamic tract

These tracts ascends to brainstem

*to medulla, pons and midrain

*tracts flattened in the brain stem (spinal lemniscus)

Reaches the ventral posterolateral nucleus of the thalamus and ends here

SPINOTHALAMIC TRACT

3rd order neuron Arise from the thalamus and pass through the internal

capsule

*thalamocortical fibers pass through the medial part of the posterior limb of the internal capsule

Enters the postcentral gyrus

*sensory cortex of the cerebrum

*behind the cetranl sulcus

*same humunculus arrangement (more sensitive areas in the body have a greater representation

CORTICOSPINAL TRACT

Flow of arrangement..

1st order neuron Fibers of the 1st order neuron arise from the precentral gyrus These fibers converge and enter a small area (internal capsule) After the internal capsule the fibers enter the brain stem, pons,

and medulla

2nd order neuron Fibers of the first order neurons ends when it enters the brain

stem and synapse with second order neuron The fibers pass through the brain stem then enters the spinal

cord

CORTICOSPINAL TRACT

3rd order neuron2nd order neuron fibers in the medulla enters the

spinal cord and synapse with the 3rd order neuron

CORTICOSPINAL TRACT

CORTICOSPINAL TRACT

FLOW OF ORDER NEURONS