Lecture 8 (cortex)

Question 1

Brodmann #: Primary motor cortex

Answer 1

4

Question 2

Primary motor cortex inputs and outputs

Answer 2

input:
- VA/VL thalamus
- premotor cortex
- somatosensory cortex
Output:
- corticopsinal path
- corticobulbar path
- corticopontocerebllar path

Question 3

how is the motor homunculus of primary motor cortex represented?

Answer 3

tongue to toe - inferior/lateral to superior/medial

Question 4

A lesion that causes overexcitement of neurons in the primary motor cortex leads to _____ _____ _____, also called _____ ______.

Answer 4

convulsive epileptic seizures

- Jacksonian seizures

Question 5

lesions to primary motor cortex

Answer 5

contralateral paresis or paralysis (mostly in extremities)

Question 6

stimulation of primary motor cortex leads to?

Answer 6

• CONTRALATERAL isolated movements of the body and lower face
• BILATERAL movements of eyes, upper face, tongue, jaw, and throat muscles

Question 7

Brodman #: premotor cortex

Answer 7

6

Question 8

function of premotor cortex

Answer 8

motor planning - programs the activity of the primary motor cortex

Question 9

inputs and outputs of premotor cortex

Answer 9

input:

• somatosensory cortex
• VA/VL of thalamus
  output:
• motor cortex
• corticospinal tract

Question 10

Brodman #: supplementary motor cortex

Answer 10

6 (medial part)

Question 11

function of supplementary motor area

Answer 11

• planning and coordination of well-learned SEQUENCES of movements
• Bimanual Coordination

Question 12

damage to what brain area makes it hard to learn sequences of movements

Answer 12

supplementary motor cortex

Question 13

when working on something with two hands, what part of the brain is most active

Answer 13

supplementary motor cortex (bimanual coordination)

Question 14

brodman #: Brocas areas

Answer 14

44, 45

Question 15

what side of the brain is Brocas area important

Answer 15

left OR dominant side

Question 16

function of Brocas area

Answer 16

production of speech

Question 17

Brocas aphasia

Answer 17

expressive aphasia

• difficulty with speech production
• cant get all the words out (aware of defecits)

Question 18

Brodmans #: frontal eye field

Answer 18

8 (mostly)

Question 19

the frontal eye field is directly connected to?

Answer 19

superior colliculus

Question 20

function of frontal eye field

Answer 20

controls voluntary scanning of eye movements

Question 21

stimulation of frontal eye field

Answer 21

movements of both eyes to CONTRALATERAL side

Question 22

lesion to frontal eye field

Answer 22

both eyes deviate IPSILATERAL side (look toward the lesion) - cant look to contralateral side

Question 23

Brodman #: prefrontal cortex

Answer 23

9, 10, 11, 12

Question 24

prefrontal cortex function (involved in?)

Answer 24

• planning complex cognitive behaviours
• expression of personality
• appropriate social behaviour
• personal drive/ self inhibition

Question 25

Brodmans area divide the cortex into distinct areas based on what?

Answer 25

physical differences in cell layers

Question 26

what are the two regions of the prefrontal cortex

Answer 26

- orbitofrontal | - dorsal lateral

Question 27

In the past, a treatment for psychiatric conditions was? | this left patients with severe?

Answer 27

prefrontal leukotomy, which is a severing of the fibers connecting the prefrontal cortex to other parts of the brain. A more severe version was a prefrontal lobectomy --> lobectomy left patients with severe changes in personality, and were often unable to function independently, lacking both initiative and self- inhibition.

Question 28

Brodman #: primary somatosensory cortex

Answer 28

1, 2, 3

Question 29

what is the organization of the sensory homunculus

Answer 29

tongue to toe - inferior to superior

Question 30

what do the homunculus represent? (motor and sensory)

Answer 30

bigger areas for parts of the body that either have/ need more motor control/ coordination or greater sensation

Question 31

Lesions in primary somatosensory cortex

Answer 31

in the inability to sense touch, pain, and temperature in the contralateral body

Question 32

primary somatosensory cortex input

Answer 32

VPL/VPM of thalamus

Question 33

secondary somatosensory cortex input

Answer 33

- primary somatosensory cortex | - thalamus

Question 34

Brodmans #: parietal association cortex

Answer 34

5, 7

Question 35

function of somatosensory association cortex

Answer 35

integration of sensory information and stereognosis

Question 36

lesions to somatosensory association cortex can lead to

Answer 36

astereognosis: inability to recognize objects by touch

Question 37

Brodman #: primary visual cortex

Answer 37

17

Question 38

primary visual cortex recieves projections from ?

Answer 38

lateral geniculate nucleus of the thalamus

Question 39

lesions of V1 lead to hemianopsia | - what are the 3 types that result form lesions to V1?

Answer 39

- contralateral homonymous hemianopsia: lose info from contralateral visual field (if lesion is superior and inferior of visual cortex) - inferior quadrantic hemianopsia - superior quadrantic hemianopsia

Question 40

damage to the upper right primary visual cortex will lead to the loss of ? This is called?

Answer 40

lower left visual field | - left inferior quadrantic hemianopsia (named for the location of the visual field lost not the location of the lesion)

Question 41

input of secondary visual cortex

Answer 41

primary visual cortex and thalamus

Question 42

function of secondary visual cortex

Answer 42

analysis of movement, colour, and other properties of visual experience

Question 43

Brodman #: primary auditory cortex

Answer 43

41

Question 44

Brodman #: secondary auditory cortex

Answer 44

42

Question 45

primary auditory cortex recieves input from

Answer 45

medial geniculate nucleus of the thalamus via internal capsule

Question 46

bilateral lesion of primary auditory cortex

Answer 46

``` cortical deafness (ears still work but brain not getting info) --> (has to be bilateral because info from both ears going to both sides of brain) ```

Question 47

secondary auditory cortex recieves info from?

Answer 47

primary auditory cortex and thalamus

Question 48

brodman #: auditory association cortex

Answer 48

22

Question 49

auditory association cortex input

Answer 49

primary and secondary auditory cortex

Question 50

auditory association cortex function

Answer 50

``` sound interpretation (makes sense of what we are hearing) ex, knowing it is a phone that is ringing ```

Question 51

brodman #: wernickes area

Answer 51

22 and 39

Question 52

wernickes area function

Answer 52

understanding of written and spoken language

Question 53

wernickes area is larger in the _____ hemispheres, and is connected to brocas area via ?

Answer 53

dominant (usually left) | - arcuate fasciculus (need to understand what you are saying)

Question 54

what do commissural fibers do? name the 3

Answer 54

- project to contralteral hemispheres 1. corpus callosum 2. anterior commissure 3. posterior commissure

Question 55

what do association fibers do name 3

Answer 55

- project within hemisphere 1. superior longitudinal fasciculus 2. unicate fasciculus 3. arcuate fasciculus

Question 56

what do projection fibers do? name 2

Answer 56

project between subcortical structures and the cortex 1. internal capsule 2. corona radiata

Question 57

Superiorly, the internal capsule fans out to form the ____ _____, and inferiorly the fibers funnel down into the _____ _____

Answer 57

corona radiata | cerebral crus

Question 58

brodman #: visual association cortex

Answer 58

18, 19