Sensation and Perception

Question 1

What is the somatosensory system

Answer 1

the part of the sensory system serving the body wall and limbs

Question 2

What are the three main levels of neural integration in the somatosensory system

Answer 2

1. Receptor level
2. Circuit Level
3. Perception Level

Question 3

What is the receptor level of the somatosensory system

Answer 3

sensory receptors and
primary sensory neuron

Transmission to CNS

Question 4

What is the circuit level of the somatosensory system

Answer 4

processing in ascending
pathways (second order sensory neuron, spinothalamic or medial lemniscus PLUS third order thalamocortical

Question 5

What is the perception level of the somatosensory system

Answer 5

processing in cerebral
cortex, interpretation of input into primary and association sensory cortex

Question 6

a pebble in your shoe causes the _____ of localized deep pressure,
but your _______ of it is an awareness of discomfort.

Answer 6

sensation, perception

Question 7

What are the three neurons involved in processing at the circuit level

Answer 7

1. First order neurons
2. Second order neurons
3. Third order neurons

Question 8

What is the first order neuron involved in processing at the circuit level

Answer 8

Conduct impulses from the skin to the spinal cord or brain stem.

Some branches take part in local spinal cord reflexes. Others synapse
with second-order sensory neurons.

cell body resides in dorsal root or cranial ganglia

Question 9

What is the second order neuron involved in processing at the circuit level

Answer 9

transmit impulses to the thalamus or cerebellum where they
synapse.

reside in the dorsal horn of the spinal cord or medullary nuclei

Interneurons

Question 10

What is the third order neuron involved in processing at the circuit level

Answer 10

located in the thalamus

conduct impulses to the somatosensory cortex of the cerebrum. (There are no third-order neurons in the cerebellum.)

Interneurons