Neural Pathways

Question 1

Neural Pathways(3)

Answer 1

1) Consist of tracts and Nuclei 2) Can be ascending(sensory) or descending(motor) 3) most decussate(cross)

Question 2

Sensory (ascending pathways) 3 types and neurons#

Answer 2

Uses 2-3 Neurons 1)Primary 1st order 2) Secondary 2nd order 3) Tertiary 3rd Order

Question 3

Primary Sensory pathway

Answer 3

Dendrite: sensory receptor Soma: dorsal root ganglion or sensory ganglion of cranial nerve

Question 4

Secondary Sensory Pathway

Answer 4

Interneuron: Axon in Thalamus(conscious) or cerebellum(unconscious)

Question 5

Tertiary Sensory Pathway

Answer 5

Interneuron; Soma in Thalamus

Question 6

Posterior Funiculus-medial lemniscal FUNCTION

Answer 6

Conducts info related to LIMB Position discrimitive touch; precise pressure vibration (3 NEURONS)

Question 7

Posterior Funiculus-medial lemniscal Pathways(1st 2nd 3rd)

Answer 7

1st) Enter SC and ascends in fascicules cuneatus or fasciculus gracilis 2nd) Synapse w 2 in medulla (decussate) axons project to thalamus 3rd) 2nd synapse with 3rd can carries impulse to cerebral cortex

Question 8

Anterolateral pathway Function

Answer 8

Conducts info related to crude touch & pressure; pain; & temperature

Question 9

Anterolateral pathway 2Parts

Answer 9

Anterior spinothalamic tract and Lateral spinothalamic tract

Question 10

Anterolateral pathway 1st 2nd 3rd

Answer 10

1st)1st synapses w/ 2nd in posterior horn 2nd)Decussate before ascending (white commissure) 3rd synapses w/ 3rd at thalamus 3rd) 3rd goes to cerebral cortex

Question 11

Spinocerebellar Pathway 2 parts and difference

Answer 11

1) Anterior spinocerebellar tract (Trunk; lower limbs) 2) Posterior spinocerebellar tract (also includes UPPER LIMB)

Question 12

Spinocerebellar Pathway Function

Answer 12

Conducts info that coordinates body movement and maintains posture

Question 13

Spinocerebellar Pathway Synapses (1-3)(anterior vs posterior)

Answer 13

1st) 1st synapses w/ 2nd at posterior horns 2nd) 2nd goes to cerebellum (Anterior: decussates in SC Posterior: does not decussate)

Question 14

Motor (descending) pathways(3)

Answer 14

1) Have upper and lower motor neurons 2)Direct (pyramidal): conscious control of sk muscle (Originate in cerebral cortex ) 3)Indirect (extrapyramidal): unconscious control of sk muscle (Originate in brainstem)

Question 15

Direct Motor pathway

Answer 15

(pyramidal) conscious control of sk muscle (Originate in cerebral cortex)

Question 16

Indirect Motor Pathway

Answer 16

(extrapyramidal): unconscious control of sk muscle Originate in brainstem

Question 17

Corticobulbar tract Char

Answer 17

Forms Primary Motor Cortex UMN synapses w/ LWN in brainstem (LMN forms several cranial nerves controlling) EYES/facial throat muscles back and neck

Question 18

Corticobulbar track What type

Answer 18

DIRECT Motor

Question 19

Corticospinal Tract Type

Answer 19

Direct motor

Question 20

What does the Corticospinal tract From

Answer 20

Bulges in the Medulla(PYRAMIDS)

Question 21

Lateral Corticospinal tract

Answer 21

UMN decussate in medulla; UMN in lateral funiculus synapse to LMN in ANTERIOR HORN LMN TO SK MUSLCE PERFORMING SKILLED MOVEMENT

Question 22

Anterior Corticospinal Tract

Answer 22

UMN in anterior funiculus; UMN decussate in SC Synapse to LMN in anterior Horn; LMN to AXIAL SK MUSCLE

Question 23

Rubrospinal Tract Type and what is regulates

Answer 23

Indirect(unconscious) Motor; Regulates precise movements and tone of limb flexor muscles

Question 24

Rubrospinal Tract Originates?

Answer 24

Red nucleus of Mesencephalon(brain stem)

Question 25

Reticulospinal tract Type and Function

Answer 25

1) Indirect Motor 2) Controls unskilled automatic movement related to pasture and balance

Question 26

Reticulospinal tract Originates

Answer 26

Reticular formation of mesencephalon