Nervous System Pathways

Question 1

Perception

Answer 1

conscious awareness of stimulus
occurs when stimulus reaches post central gyrus

Question 2

sensory receptors

Answer 2

made of unipolar neurons
stimulus travels on peripheral axon to dorsal ganglion
pick up sensory stimulus

Question 3

somatic sensations

Answer 3

stimulus

Question 4

dorsal column medial lemniscus tract

Answer 4

touch/proprioception
1- receptor at stimulus travels via peripheral axon through the DRG and up the spinal cord
2- synapse at the medulla, crosses over to opposite side of the brain. Travels to thalamus
3- synapses at thalamus, then travels to post central gyrus when we become aware of the stimulus

Question 5

spinothalamic pathway

Answer 5

temperature/pain
1- receptor to spinal cord
2- synapses in dorsal root, travels up spinal cord, through brain stem into the thalamus
3- synapses onto 3rd order neuron, travels up to post central gyrus

Question 6

somatic sensory paths

Answer 6

3 neurons involved in getting stimulus to post central gyrus were one can be conscious of its happening

Question 7

somatosensory cortex

Answer 7

post central gyrus, processes sensory information gathered by the PNS

Question 8

sensory homunculus

Answer 8

post central gyrus

Question 9

motor cortex

Answer 9

located in the precentral gyrus
controls motor output based on sensory input

Question 10

motor homunculus

Answer 10

pre central gyrus

Question 11

somatic motor paths

Answer 11

use 2 neurons
1- pre central gyrus to spinal cord ventral horn. Decisates in the medulla (crosses back to the original side of the stimulus)
2- synapse onto second order (lower motor) neuron to go the rest of the way to the effector tissue

Question 12

corticospinal

Answer 12

GSE pathway
makes up the upper motor neurons
from the cortex to the spine