TRACTS

Ascending tracts

• extremities to the brain

• sensory data

Descending Tracts

• from brain or brainstem to the extremities

• motor data

• Anterior and lateral SPINOTHALAMIC

• Dorsal Column Medial Lemniscus

• Dorsal and Ventral SPINOCEREBELLAR

• Spinoreticular System

What are the ascending tracts?

SPINOTHALAMIC TRACT

• Pain and temperature

anterior white matter

Anterior spinothalamic tract goes to

lateral white matter

Lateral spinothalamic tract goes to

Axon: Peripheral Nerve

What is the Axon of neuron 1 in the spinothalamic tract?

at the spinal cord

Where does the lateral spinothalamic tract decussate?

Dorsal Column Medial Lemniscus

Receives conscious proprioception, vibratory sense, 2 point discrimination, and tactile sense

Fasciculus Cuneatus

• for upper extremity in the DCML

Fasciculus Gracilis

• for lower ex in the DCML

Axon: Peripheral Nerve, fasciculus gracilis, fasciculus cuneatus

What is the axon in neuron 1 of the DCML?

Axons decussate the the MEDULLA

Where do the axons decussate in neuron 2 of the DCML?

Axon: Media Lemniscus

What is the axon of neuron 2 in the DCML?

SPINOCEREBELLAR TRACT

• for unconscious proprioception from the extremities for balance and head-trunk coordination and brings them to the cerebellum

Muscle spindle

Where does neuron 1 start in the spinocerebellar tract?

Dorsal nucleus of clarke

Where does the neuron 1 end in the spinocerebellar tract?

at the spinal cord

In the ventral tract of the SCT, where do the axons decussate?

1. corticospinal

2. cotricobulbar

3. rubrospinal

4. retibulospinal

5. vestibulospinal

What are the descending tracts?

Lower motor neurons

commanded by the upper motor neurons

• always connected to IMN

• Cannot act with no command from UMN

• ventral horn

• ventral root

• peripheral nerve

What comprises the LMNs?