Lecture 17: Association Cortex and Cognition

Question 1

what is the unimodal association cortex

Answer 1

2nd level of processing, but still of just 1 sense

Question 2

what is Heteromodal association cortex.

Answer 2

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

Question 3

do unimodal or heteromodal association cortices take up more of the brain

Answer 3

heteromodal association cortices take up most of the cerebral surface of the brain

Question 4

what are the three kinds of cognition

Answer 4

Attending to complex stimuli (Parietal cortex)

Identifying these stimuli (Temporal Cortex)

(Responding) Planning appropriate responses (Frontal Lobes)

Question 5

what does damage to the right side of the parietal lobe cause

Answer 5

left sided neglect

Question 6

what does damage to the left side of the parietal lobe cause

Answer 6

apraxia

Question 7

what does damage to the right side of the temporal lobe cause

Answer 7

visual agnosia

Question 8

what does damage to the left side of the temporal lobe cause

Answer 8

aphasia

Question 9

Each cortical region of the heteromodal association cortices have 4 distinct connections:

Answer 9

1. Primary source of inputs and outputs
2. Vertical and horizontal axis connections
3. Radial alignment
4. Inter-neurons connect functionally similar cell groups

Question 10

what are the 3 Primary source of inputs to the heteromodal association cortices

Answer 10

thalamus

other cortical areas

brainstem modulatory systems

Question 11

does the thalamus only receive information from the extremities?

Answer 11

no, it also receives info from the cortex (the head)

Question 12

which 2 nuclei in the thalamus receive information from the cortex

Answer 12

Medio-dorsal thalamus

Pulvinar Nuclei

Question 13

what is the input and output of the Medio-dorsal thalamus

Answer 13

input: cortex

output: Frontal association cortex

Question 14

what is the input and output of the Pulvinar Nuclei

Answer 14

input: cortex

output:
Parietal association cortex

Question 15

how do the main sources of input (other cortical areas) provide input to the heteromodal association cortices

Answer 15

Ipsilateral connections

Inter-hemisheric connections

Question 16

what is the main source of input to association cortices

Answer 16

Other cortical areas (cortico-cortical connections)

Question 17

what are Ipsilateral connections

Answer 17

From primary and secondary sensory and motor cortices on same side of the brain. (left parietal communicating with left temporal)

Question 18

what are Inter-hemisheric connections

Answer 18

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

(right parietal communicating with left temporal)

Question 19

what are the 3 Brainstem modulatory centres

Answer 19

turn overall activity up or down.

upper brainstem

upper brain stem +reticular formation

basal forebrain

Question 20

what are Vertical and horizontal axis connections

Answer 20

cells that do similar things are grouped together in the 6 levels

Question 21

Where do association cortices get the majority of their input?
a) Axons from the periphery
b) The frontal lobe
c) Other parts of the brain

Answer 21

Other parts of the brain

Question 22

what is the content of consciousness

Answer 22

Memory, emotion and drives, language, executive function

Question 23

what is the Level of Consciousness

Answer 23

The three A’s

1.Alertness
2.Attention
3.Awareness

Question 24

what are the Four key brain areas that sustain the level of consciousness

Answer 24

the consciousness system networks

1. Upper brainstem
2. Thalamus
3. Hypothalamus
4. Basal forebrain

Question 25

what is the diencephalon

Answer 25

thalamus together with hypothalamus

Question 26

to have alterness, what needs to be functioning

Answer 26

* Consciousness system network * Cortex

Question 27

to have attention, what needs to be functioning

Answer 27

* Consciousness system network * Cortex + fronto-parietal association cortex

Question 28

to have awareness, what needs to be functioning

Answer 28

Ability to combine various higher-order forms of information from disparate regions into a unified and efficient summary of mental activity - which can be remembered at a later time.

Question 29

what are the 4 Brain centres involved in alertness

Answer 29

Brainstem Diencephalon Basal Forebrain Cortex

Question 30

what are the 2 Determinants of alertness

Answer 30

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

Question 31

do all brainstem modulatory systems use the same neurotransmitters

Answer 31

each system uses different neurotransmitters and impacts either alertness or cognitive processes

Question 32

Which brain regions provide input to the upper brain stem and reticular formation for alertness?

Answer 32

Ascending sensory inputs (like pain) Frontoparietal association and limbic cortices (emotions) Hypothalamus (fight or flight)

Question 33

What happens when we damage brainstem modulatory systems

Answer 33

Lack of alertness / consciousness.

Question 34

what are the 3 levels of Lack of alertness / consciousness

Answer 34

coma vegetative state minimally conscious

Question 35

what happens in the brain during a comma

Answer 35

severely depressed brain function no Psychologically meaningful or purposeful responses May show: Reflexive eye movements * Respiratory movements * Posturing

Question 36

what is decorticate posturing during coma

Answer 36

damaging to corticospinal track, flexor pattern

Question 37

what is decerebrate posturing during coma

Answer 37

worse outcome, damage to rubrospinal track, more damage to brainstem

Question 38

what is a vegetative state

Answer 38

No meaningful responses, speech or gestures, but may: Open eyes and arouse in response to stimulation May turn eyes and heads toward auditory and tactile stimulation have unintelligible sounds

Question 39

what is a Minimally conscious state

Answer 39

Can occur after the vegetative state OR as a primary state Appearance of visual tracking may be one of earliest signs. Minimal or variable degree of responsiveness * Simple commands * Single words * Reach/hold objects Not reliable yes/no

Question 40

what does acetylcholine as a neurotransmitter do

Answer 40

goes all over the brain to help with alertness and memory without acetylcholine, we see depressed brain function

Question 41

what does dopamine as a neurotransmitter do

Answer 41

focuses on the frontal part of the cortex alertness and memory crucial for sustained attention (concentration)

Question 42

what are the 4 neurotransmitters released?

Answer 42

acetylcholinr dopamine norepinephrine serotonin