Midterm 2 - Unit 3 Lecture 3

Question 1

The nervous system can use visual and kinesthetic input to

Answer 1

control movement
control parameters of motor commands
to trigger commands
to correct errors in trajectory

Question 2

From visual cortex, information goes to

Answer 2

Two visual systems (pathways):
Dorsal Stream (where)
Ventral stream (what)

Question 3

Dorsal Stream (where) function

Answer 3

involved in spatial awareness and guidance of actions (e.g., reaching).

Question 4

Where does the dorsal stream project to

Answer 4

posterior parietal cortex

Question 5

Ventral stream (what) function

Answer 5

recognition and discrimination of visual shapes and objects

Question 6

Where does the Ventral stream project to

Answer 6

temporal cortex

Question 7

what is Proprioception

Answer 7

Sense of limb movement

Question 8

First-order sensory neurons transmit information from…

Answer 8

peripheral receptors to the medulla

Question 9

what is the dorsal column medial lemniscal pathway

Answer 9

is a sensory pathway of the central nervous system that conveys sensations of fine touch, vibration, two-point discrimination, and proprioception (position) from the skin and joints

Question 10

how does the dorsal column medial lemniscal pathway receives information

Answer 10

from sensory receptors throughout the body,

Question 11

what are the three groupings of neurons that are involved in the dorsal Column-Medial Lemniscus pathway:

Answer 11

first-order neurons
second-order neurons
third-order neurons

Question 12

what are first-order neurons

Answer 12

are sensory neurons located in the dorsal root ganglia, that send their afferent fibers through the two dorsal columns – the gracile tract, and the cuneate tract

Question 13

where do the first-order neurons make contact with the second-order neurons

Answer 13

in the lower medulla

Question 14

second order neuron send signal from

Answer 14

medulla to contralateral Thalamus

Question 15

third-order neurons carry signal from

Answer 15

thalamus to somatosensory cortex

Question 16

where does the signal go from the third-order neurons

Answer 16

Thalamus to Somatosensory cortex

Question 17

what is the anterolateral pathway

Answer 17

an ascending pathway that conveys pain, temperature (protopathic sensation), and crude touch from the periphery to the brain.

Question 18

what are the three main pathways that the anterolateral pathway is comprised of

Answer 18

Spinothalamic(thalamus)
Spinoreticular(pons)
Spinomesencephalic (midbrain)

Question 19

How do neurons travel in the Spinothalamic(thalamus) tract

Answer 19

starts with the dorsal root ganglions (These dorsal root ganglia lie adjacent to the spinal cord and represent the first-order neuron of the spinothalamic tract pathway)

Cross midline (over 2-3 segments)
(Ascend in anterolateral white matter)
Thalamus

Somatosensory cortex

Question 20

function of Somatosensory Cortex

Answer 20

processing afferent somatosensory input and contributes to the integration of sensory and motor signals necessary for skilled movement.

Question 21

Information from the somatosensory cortex relays to…

Answer 21

secondary somatosensory cortex and parietal cortex for integration

Question 22

function of pareital cortex

Answer 22

integrate information on proprioception, touch, space navigation, and language processing.

Question 23

Visual, kinesthetic or both? in regards to movement

Answer 23

Find that when both are available, a weighted combination of sensory information is used

Vision and proprioception are used to guide reaching movements

Likely use whichever is better for the task
Proprioception for finely controlled movements like handwriting, piano playing
Vision for movements to targets in extrapersonal space

Question 24

Vestibular System Function

Answer 24

Involved in the control of balance
Positioning of head and neck
Controls eye muscles/reflexes

Question 25

how are Vestibular signals carried

Answer 25

via vestibulo-cochlear nerve (CN VIII) to ipsilateral vestibular nuclei

Question 26

how does visual info travel

Answer 26

eyes
visual cortex or brain stem
From the visual cortex, visual information divides further into the dorsal stream (for action) and the ventral stream (for recognition)

Question 27

how does Proprioceptive information travel

Answer 27

spinal cord (for reflexive movements)
higher brain centres (sensory cortex, then integrated in parietal cortex)