Cognition and the Association Cortex

Question 1

What is cognition?

Answer 1

1. Internal life: perception, attention, memory language planning, emotion

2. Invovles integrating information–> perceptual whole, guides choice of app behaviors
3. Occurs between a stimulus and a response (attention, recognition, planning

Question 2

What is a default network?

Answer 2

Active at REST

Day dreaming, mind wandering, memories, moral dilemas

Often more active w/ mental illness

Question 3

What is a time positive netowrk?

Answer 3

Active when performing tasks

Question 4

Where do unimodal and multimodal integration take place and what are they?

Answer 4

Both take place in the association cortex.

Unimodal- integrates info from ONE sensory modality

Multimodal- integrates info ACROSS sensory modalities and from other sources

Question 5

Describe “information flow” from the primary sensory cortex to the motor cortex.

Answer 5

Primary sensory cortex

unimodal

multimodal

premotor

motor

Question 6

What is cortical lamination? How many cortex layers are there?

Answer 6

Density of cells throughout the cortex is NOT unriform.

6 layers

Question 7

Where are pyramidal and stellate cells found?

Answer 7

Pyramidal: layers 1-3

Stellate: 4-6

Question 8

Layer 4 from the primary sensory cortex gets input from?

Answer 8

Sense specific thalamic nuclei!

Layesr 1,2,3, and 5 get input from other cortical areas.

Question 9

What are the sense specific nuclei?

Answer 9

Retina > LGN > primary visual cortex

Cochlea > brainstem nuclei > MGN > primary auditory ctx

Skin > medial leminiscus > VPL > primary somatosensory ctx

Question 10

Layer 4 in the sensory association cortex gets info from where?

Answer 10

Multimodal thalamic nuclei!

Other layers receive information from other cortical areas

Question 11

What are the multimodal thalamic nuclei?

Answer 11

Sup. colliculus (visual) > Pulvinar > Pariotemporal/VAC

SC, Olf cortex, amygdala, ventral pallidum > Medial dorsal > FEF, VAC, Ant cingulate, striatum

Lateral Posterior

Input: Assoc cortex, ant. cingulate, retina

Output: parietal and visual assoc. cortex, ant. cingulate, striatum

Anterior

Input: Hypothal, hippo, cingulate

Output: post. cingulate

Question 12

Which has the higher density of corticocortical connections? PSC or SAC?

Answer 12

the association cortex has a higher density

Question 13

Where do modulatory inputs come from?

Answer 13

Thalamus (1)

brainstem (all 6 layers)

Question 14

What is the function of the association cortex?

Answer 14

1. Integrate input from different modalities
2. Mediate between sensory inputs and appropriate behavioral outputs

Question 15

What is associated with the parietal association cortex?

Answer 15

Non-dominant:

1. Selective Attention- “gate”
2. Stroop Test- test deficits in selective attention (WHITE)
3. Damage: Spatial neglect (posterior parietal cortex)

Dominant:

1. Skilled movements
2. R-L orientation
3. Damage: Motor apraxia (intraparietal sulcus)

Question 16

What is associated with the Temporal association cortex?

Answer 16

1. Language and social attn (superior temp. sulcus)
2. Recognition (inferior temp. sulcus)
3. Damage: Agnosias (inferior temp. sulcus)

Question 17

Prosopagnosia

Answer 17

FACES

bilateral lesion of ITC

Question 18

Visual agnosia

Answer 18

can’t recognize OBJECT

unimodal visual cortex

Question 19

ASterognosia

Answer 19

can’t recog obj by TOUCH

unimodal senosry cortex

Question 20

Associative visual agnosia

Answer 20

Can identify but can’t NAME

posterior parietal cortex

Question 21

Finger agnosia

Answer 21

Gerstmann synd: finger agnosia acalaulia, agraphia and R-L confusion

angular gyrus of dom. parietal cortex

Question 22

What test can be used to test the frontal assoc. cortex?

Answer 22

Wisconsin Card sorting test

Cards- color, shape, number

See how quickly pt picks up on rules

Tests cognitive flexibility and ordered thinking