Association Cortices

Question 1

what is the function of the heteromodal association cortex?

Answer 1

puts together information provided by various unimodal association areas to accomplish more complex functions

Question 2

what makes up most of the cerebral surface of the brain?

Answer 2

heteromodal association cortices

Question 3

what are the heteromodal association cortices responsible for?

Answer 3

complex processing that goes on between the arrival of input to the primary sensory cortices and the generation of behaviour

Question 4

what components can cognition be divided into?

Answer 4

1. attending to complex stimuli (parietal cortex)
2. identifying complex stimuli (temporal cortex)
3. responding to complex stimuli (frontal cortex)

Question 5

what is cognition?

Answer 5

process by which we come to know the world

Question 6

if we have a lesion to the right parietal cortex what do we typically see?

Answer 6

unilateral neglect

Question 7

if we have lesion to the left parietal cortex what do we typically see?

Answer 7

apraxia

Question 8

what is apraxia?

Answer 8

(difficulty with small coordinated movements)

Question 9

if we have damage to the right temporal cortex what do we typically see?

Answer 9

visual agnosias

Question 10

if we have damage to the left temporal cortex what do we typically see?

Answer 10

difficulties with language

Question 11

what do some people say is the one thing that makes us human?

Answer 11

the frontal cortex

Question 12

what is the neocortex?

Answer 12

described most of the cortex covering the cerebral hemispheres

Question 13

how many layers does the neocortex have?

Answer 13

6 cellular layers with distinct cell populations:
-density
-size
-shape

Question 14

each cortical region of the neocortex has distinct connections, what are they?

Answer 14

1. primary source of inputs and outputs
2. vertical and horizontal axis connections
3. radial alignment
4. inter-neurons connect functional similar groups

Question 15

what are the 3 main inputs of the heteromodal cortex?

Answer 15

1. thalamus
2. other cortical areas
3. brainstem modulatory systems

Question 16

what areas of the thalamus receive information from the cortex (down from the brain)?

Answer 16

mediodorsal nucleus of the thalamus
pulvinar nucleus of the thalamus

Question 17

where does the mediodorsal nucleus of the thalamus send information out to?

Answer 17

frontal association cortex

Question 18

where does the pulvinar nucleus of the thalamus send information out to?

Answer 18

parietal association cortex

Question 19

are the nuclei used for primary, sensory, and motor functions involved in higher level processing?

Answer 19

no

Question 20

wata re the main sources of input to association cortices?

Answer 20

1. ipsilateral connections
2. inter-hemispheric connections

Question 21

what are ipsilateral connections?

Answer 21

from primary to secondary sensory and motor cortices on same side of brain

Question 22

what are inter-hemispheric connections?

Answer 22

from corresponding and non-corresponding regions of cortex on the other side of the brain (via corpus callous and anterior commissure)

Question 23

what is an example of a corresponding cortical area?

Answer 23

the right temporal association cortex is sending information to the left temporal association cortex

Question 24

what is an example of a non-corresponding cortical area?

Answer 24

the left temporal association talking to the right parietal association cortex

Question 25

what are the brainstem modulatory centres like?

Answer 25

dimmer switches

Question 26

what do the brainstem modulatory centres do?

Answer 26

they emit neurotransmitters they turn the overall activity in the brain either up or down

Question 27

where are the brainstem modulatory centres?

Answer 27

1. upper brainstem 2. upper brainstem +reticular formation 3. basal forebrain

Question 28

what are the 4 main outputs to the heteromodal association cortices?

Answer 28

1. other cortical areas (ipsilateral) 2. other cortical areas (contralateral) 3. subcortical structures 4. thalamus

Question 29

does each layer of the neocortex have vertical or horizontal connections?

Answer 29

both!

Question 30

in the neocortex, cells with similar functions are wired together into what?

Answer 30

columns arranged radially

Question 31

what is the content of consciousness?

Answer 31

things like what makes us unique individuals: memory, emotions, motor/sensory functions ex. little voice in your head that makes you you

Question 32

what is the level of consciousness divided into?

Answer 32

alertness attention awareness

Question 33

what is level of consciousness sustained by?

Answer 33

consciousness system networks

Question 34

what are the 4 key brain areas that sustain the consciousness system networks?

Answer 34

1. upper brainstem (midbrain) 2. thalamus (diencephalon) 3. hypothalamus (diencephalon) 4.basal forebrain (bottom of the front of the brain)

Question 35

in order to be alert what do we need?

Answer 35

consciousness system network some activity in the cortex in general

Question 36

in order to be attending, what do we need?

Answer 36

same circuits as alertness fronto-parietal association cortex

Question 37

what is awareness?

Answer 37

the ability to perceive, to feel, to be conscious of events, objects, or sensory patterns

Question 38

what are the bran areas involved in alertness?

Answer 38

brainstem diencephalon basal forebrain cortex

Question 39

what are the determinants of alertness?

Answer 39

1. neuromodulatory systems in the brainstem 2. the cortical regions to which these neuromodulatory systems project

Question 40

what are neuromodulatory stems sometimes called?

Answer 40

subcortical arousal system

Question 41

what does each brainstem neuromodulaotry system impact?

Answer 41

either alertness or cognitive processes

Question 42

what are the 3 main ways alertness is increased?

Answer 42

1. ascending sensory inputs (eg. anterolateral pathway) ex. pain can increase alertness such as getting a vaccine 2. frontoparietal association and limbic cortices ex. cognitive and emotional processed can modulate alertness (having relationships issues) 3. hypothalamus ex. fight or flight (hearing something at nighttime)

Question 43

what happens when we damage these systems?

Answer 43

overall lack of alertness/consciousness

Question 44

what are the 3 distinct levels of lack of consciousness?

Answer 44

coma vegetative state minimally conscious state

Question 45

if someone is dead how much function is there in their brain?

Answer 45

none, absent

Question 46

what do we see a lack of in terms of consciousness in a coma?

Answer 46

lack of purposeful responses (anything that requires the cortex to process and plan)

Question 47

what may a person in a coma show?

Answer 47

reflexive eye movements respiratory movements posturing

Question 48

what is the lowest level of a lack of consciousness?

Answer 48

coma

Question 49

what are the 2 main types of posturing?

Answer 49

decorticate (damage to corticospinal tract) decerebrate (damage to the rubrospinal tract)

Question 50

is decorticate or decerebrate posturing worse?

Answer 50

decerebrate

Question 51

what will we not see in someone in a vegetative state?

Answer 51

no meaningful responses, speech or gestures

Question 52

what may we see in someone in a vegetative state?

Answer 52

open eyes and arouse in response to stimulation (pain input may cause this briefly) may turn eyes and head toward auditory and tactile stimulation may make unintelligible sounds

Question 53

does the minimally conscious state have to occur after the vegetative state?

Answer 53

it can occur after or as a primary state

Question 54

what may be one of the earliest signs in minimally conscious state?

Answer 54

visual tracking

Question 55

in a minimally conscious state, do people have a reliable yes/no?

Answer 55

No

Question 56

how can be measure consciousness?

Answer 56

Glasgow coma scale

Question 57

what area of the brain is severely depressed when someone has locked in syndrome?

Answer 57

upper brainstem (pyramidal decussation)

Question 58

what does acetylcholine do?

Answer 58

allows us to be really alert and remember things

Question 59

without what neurotransmitter and we not very likely to be alert?

Answer 59

acetylcholine

Question 60

what part of the brain does acetylcholine go too?

Answer 60

very broad projections, all over the brain

Question 61

what does dopamine do?

Answer 61

movement and initiative alertness and attention

Question 62

what brain structure is very important for attention?

Answer 62

prefrontal cortex

Question 63

what brain area sends dopamine to the prefrontal cortex?

Answer 63

ventral tegmental area

Question 64

what is crucial for sustained attention and concentration?

Answer 64

dopamine