Executive Function II

Question 1

Miller and cohen model of prefrontal cortex and cognitive control= describe generally

Answer 1

approximation of what going on in brain
In absence of top down control from Pfc = diff output pathways compete for expression in response to stimulus (green in red font)
Mapping between the stimulus and saying green = very strong, so that response expressed and inhibited alternative response = saying red

Question 2

Miller and cohen model of prefrontal cortex and cognitive control= describe diagram

Answer 2

Green in red font stimulus = connected to 2 diff responses
2 sensory motor pathways (internal nodes), 1= see green so say green, 2=see red so say red
Green pathway = much stronger, normally when no top down control, winning pathway = suppress losing pathway - automatic output expressed

Question 3

Miller and cohen model of prefrontal cortex and cognitive control= what does pfc do

Answer 3

Provides bias signal that amplifies selected response = red and results in hit ion of alternative response = green
Pfc uses its knowledge of rules, or gaols to direct traffic in other brain regions

Question 4

Miller and cohen model of prefrontal cortex and cognitive control= Describe Pfc

Answer 4

Exerts cogntiive control = top down
Applies bias to one pathway and turns it up = amplifies reposne that requires mental effort and inhibits more automatic response

Question 5

Miller and cohen model of prefrontal cortex and cognitive control= how to make model work

Answer 5

Need some part of system of Pfc to exert top down control
Need way to monitor behaviour for errors = capcity to monitor behaviour/errors

Question 6

miller cohen model = what is involved in monitoring behaviour and detecting errors

Answer 6

Anterior cingulate cortex
Region lights up when making errors and when task become harder= involved in monitoring behaviour
Medial region brain

Question 7

miller cohen model = what is involved in top down control

Answer 7

Lateral Pfc

Question 8

system 1

Answer 8

Rapid, automatic, intuitive
Use most fo time
Not thinking just do - things predictable, make decisions but hard = mental effort so just go with what feels best, heuristic, basic rules of operations that enable us to make decisions
Packaged in system
Can’t not see world = see green
A lot of things we do = don’t have to think about them

Question 9

system 2

Answer 9

Requires attention and mental effort
Cognitive control - think it through

Question 10

what does cognitive control involve

Answer 10

Interactions between brain networks that connect Pfc and parietal lobes along with other cortical and subcortical structures
Executive systems = involve various neural networks = connect frontal lobes to other Regions of brain, brain not isolated, diff regions frontal lobe interact with other parts of cortex —> form networks

Question 11

name and briefly describe the 4 networks

Answer 11

Dorsal frontoparietal network = attention
Lateral frontoparietal network = control
Midcingulo-insular network = salience
Medial frontoparietal network = default

Question 12

fmri

Answer 12

Changes in metabolism - small changes = measures tehse, more oxygenated blood flows to actiavte brain regions
Indirect
Have to do control task and compare different bewteen conditons

Question 13

describe default mode network = specifically

Answer 13

Active when mind turned inwards
Involved in thoughts about yourself, episodic memeory, social cognition and mind wandering - ongoing internal narrative of life
Decrease activity when re orient attention to engage in world around you

Question 14

describe default mode network =generally

Answer 14

Before exp = just sitting and waiting, regardless of task = has specific brain regions that decrease activity when doing task, so some areas active when daydreaming and reduce activity when tend to task
= regions collectively referred to as default mode network
Decrease in activity when start to engage in cognitively demanding task

Question 15

describe default mode network = key cortical nodes

Answer 15

Medial Pfc
Medial parietal lobe (posterior cingulate cortex and precuneus) - important tole in episodic memory = narrative of life, story lined up in time
Angular gyrus

Frontal regions involved in self awareness and self reflection

Question 16

what happens when shift internal thoughts to engage in world

Answer 16

Activity in default mode network decreases = reduces activity when do task
Activity increases in networks involved in attention and cognitive control
Stop ruminating = turns attention outwards to grapple with task

Question 17

descrbe Control network

Answer 17

Lateral frontoparietal network
Cognitive control network = apply mental effort
Sypramarginal gyrus (parietal lobe regions) and lateral Pfc

Question 18

describe attention network

Answer 18

Dorsal attention network = redirecting attention to something out in external world
Intraparietal sulcus - parietal lobe regions
And fontal eye fields = control rapid eye movements, shifts attention so shift eye movements

Question 19

describe salience network

Answer 19

Monitors internal and external sensory input and initiates the switch between default mode and control/attention networks
Detects need to switch, integrates sensory info from inside body and from outside world and monitors and tells when to switch attention
Anterior cingulate cortex and anterior insula(behind temporal lobes)

Question 20

what is insula involved in

Answer 20

Especially in right hemisphere
= integrates interoceptive info = relating to physiological status of tissues in body
Tells us how we feel
= tells you if what you are experience is good or not = applies subjective affective aspects of sensation
Encodes subjective feelings of experience to some extent

Question 21

Sometimes is insula referred to as

Answer 21

Limbic sensory cortex
Bc of its association with pain, temp and visceral perception

Question 22

activity in posterior regions insula

Answer 22

Corresponds to actual intensity of stimuli
Like heat applied to skin surface

Question 23

activity in anterior regions insula

Answer 23

Corrresponds to subjective feelings
Like pleasant warmth

Question 24

what is insula activated by

Answer 24

Sensory experiences but also activated by various cognitive experiences that have an emotional or sensory component

Question 25

describe what fmri shows about insula

Answer 25

Activation of right insular cortex in response to 1= recall induced anger (right insula and more anterior parts = closer to frontal lobes) 2= cooling of hand (activates s1 and insula = provides info about subejctive experience) 3= pictures of human faces showing disgust Visceral physiological competent = insula gets input from body and provides info about body states = can be elicited by stimuli in world or by emotional states Insula conveys subejctive aspect of those physiological changes

Question 26

What Is insula apart of

Answer 26

Own cortico-subcortical network = monitoring body states, arousal, emotional states, related to physiological changes going on

Question 27

what is interoception system = gen

Answer 27

Includes pain and temp sensation = more involved in how you are doing and if things good or bad physiologically, pain and temp on skin surface and monitoring internal body states Interception sensory neurons carry info about body homeostasis

Question 28

what is interoception system = what does it tell brain

Answer 28

Tells brain how you feel

Question 29

what is interoception system = what does it include

Answer 29

Afferents from sc (a delta and c fibers) and cranial nerves VII, ix and x

Question 30

what is interoception system = where do afferents project

Answer 30

Connected to brainstem structures and insula = nucleus of solitary tract (receives visceral sensory input through vagus nerve), parabrachial nucleus and periaqueductal gray (brainstem structure, response to threat)

Question 31

what is interoception system = destination of interoceptive sensory input

Answer 31

Main cortical destination for interoceptive sensory input = insula