Higher Cortical Functions

Question 1

assigned functions and cortical regions

Answer 1

pre- and post-rolandic zones: motor and sensory activities
striate occipital zones: visual perception
superior temporal gyri: auditory

Question 2

two cell types that predominate in the neocortex

Answer 2

pyramidal cells (large)
rounded (granular) cells (smaller and more numerous)

Question 3

two main types of neocortex

Answer 3

homotypical: six layers can be seen
heterotypical: has association cortex (large areas not committed to any functions)

Question 4

locations of the granular cortex

Answer 4

primary sensory cortex
postcentral gyrus
banks of the calcarine sulcus
transverse gyri of heschl (layers 2 and 4 are developed for afferent impulses)

Question 5

what are giant cells of betz

Answer 5

largest cells of the granular cortex

gives rise to some of motor fibers in CST

Question 6

locations of agranular cortex

Answer 6

frontal motor cortex (precentral cortex: areas 4 and 6)

layer 5

Question 7

how to distinguish agranular cortex

Answer 7

more pyramidal than granular cells, especially in layer 5

Question 8

four general functional categories of the brain

Answer 8

sensory
motor
unimodal association cortex
multimodal association cortex

Question 9

projections of the sensory nerves

Answer 9

thalamocortical fibers -> primary sensory areas
ventral posterior complex (thalamus) -> primary somatosensory cortex (PCG)
lateral geniculate nucleus -> primary visual cortex
medial geniculate nucleus -> primary auditory cortex

Question 10

motor function: _____ tract

sensory function: ___ tracts

Answer 10

motor: descending CST
sensory: ascending spinothalamic and dorsal column medial lemniscus

Question 11

function of unimodal association areas

Answer 11

devoted to higher level of information processing via corticocortical fibers

Question 12

locations of unimodal association areas

Answer 12

visual unimodal association cortex: visual cortex
somatosensory association cortex: posterior to post-central gyrus
auditory association cortex: superior temporal gyrus next to primary auditory cortex

Question 13

function of multimodal association areas

Answer 13

coordinate farther regions

• communication with language
• reasoning
• extrapolating future events based on present experience
• making complex and long range plans
• imagination

Question 14

basic flow of afferent and efferent stimuli integration

Answer 14

primary sensory cortex (afferent stimulation)
unimodal sensory association areas (nearby)
multimodal sensory association areas (more than one sense)
multimodal motor association area
premotor area (planning)
primary motor cortex (implementation)

Question 15

cerebral hemisphere that controls language

Answer 15

dominant hemisphere (usually left)

Question 16

t/f almost all right handed individuals and half of left handed individuals are left cerebral dominant

Answer 16

true

Question 17

what is wada test

Answer 17

to test for hemisphere dominance

• inject sodium amytal into internal carotid artery
• produce arrest of speech for 30s in dominant side
• important before temporal lobectomy for epilepsy

Question 18

responsible for the motor cortex (contralateral movement of the face, arm, leg, trunk)

Answer 18

precentral gyrus

Question 19

serves as the expressive center for speech in the dominant hemisphere

Answer 19

broca’s area

Question 20

area for contralateral head and eye turning

Answer 20

supplementary motor area

Question 21

for cortical inhibition of bladder and bowel voiding

Answer 21

paracentral lobule

Question 22

result of impairment in precentral gyrus

Answer 22

monoplegia or hemiplegia

Question 23

result of damage to broca’s area

Answer 23

broca’s dysphasia

Question 24

result of damage to supplementary motor area

Answer 24

paralysis of head and eye to opposite side (head turns towards diseased hemisphere and eye look in the same direction)

Question 25

result of damage to pre-frontal areas

Answer 25

``` orbitofrontal syndrome frontal convexity syndrome medial frontal syndrome primitive reflexes disturbance of gait (apraxia) resistance to passive movements of the limbs ```

Question 26

symptoms of orbitofrontal syndrome

Answer 26

disinhibition poor judgment emotional lability

Question 27

symptoms of frontal convexity syndrome

Answer 27

apathy indifference poor abstract thought

Question 28

symptoms of medial frontal syndrome

Answer 28

akinetic, incontinent, sparse verbal output

Question 29

result of damage to paracentral lobule

Answer 29

urine and fecal incontinence

Question 30

expressive center for speech

Answer 30

supramarginal and angular gyri of the dominant hemisphere

Question 31

dominant vs non-dominant parietal lobe functions

Answer 31

dominant: calculation | non-dominant: body image, awareness of external environment, visual/proprioceptive skills

Question 32

result of damage to sensory cortex

Answer 32

postural sensation, passive movement, and accurate localization of light touch disturbed discrimination between one and two points lost difficulty in appreciation of size, shape, texture, and weight perceptual rivalry

Question 33

Gertsmann's syndrome on non-dominant side

Answer 33

anosognosia (unaware of opposite side) dressing apraxia geographical agnosia constructional apraxia

Question 34

Gertsmann's syndrome on dominant side

Answer 34

finger agnosia acalculia agraphia

Question 35

result of damage to optic radiation in parietal lobe

Answer 35

lower homonymous quadrantanopia

Question 36

function of auditory cortex

Answer 36

dominant: hearing language | non dominant: hearing sounds, rhythm, music

Question 37

function of middle and inferior temporal gyri

Answer 37

learning and memory

Question 38

function of limbic lobe

Answer 38

olfaction and emotional behavior | incorporation of inferior frontal and medial parietal structures

Question 39

result of damage to auditory cortex

Answer 39

``` cortical deafness auditory hallucinations (temporal lobe disease) ```

Question 40

result of damage to optic radiation in temporal lobe

Answer 40

upper homonymous quadrantanopia

Question 41

result of damage to limbic lobe

Answer 41

olfactory hallucination with complex partial seizure

Question 42

result of damage to middle and inferior temporal gyri

Answer 42

disturbance of memory/learning

Question 43

primary visual cortex (perception of vision)

Answer 43

striate cortex

Question 44

association visual cortex

Answer 44

parastriate cortex

Question 45

result of damage to striate cortex

Answer 45

extensive bilateral cortical lesions = cortical blindness

Question 46

anton's syndrome

Answer 46

involvement of striate and parastriate cortices | - damaged interpretation of vision

Question 47

balint's syndrome

Answer 47

bilateral parieto-occipital lesions = inability to direct voluntary gaze associated with visual agnosia