Neuro 47: Frontal cortex

Question 1

6 Mjr functions of the frontal cortex

Answer 1

“Executive Functions”

1. planning
2. reasoning
3. awareness –> of yourself (there are diff types)
4. judgement
5. problem solving
6. decision making

Question 2

Dorsal pathway: regions involved? nature of info? inputs? outputs?

Answer 2

• regions involved: temporoparietal regions
• nature of info: logical
• inputs: visual, auditory, & somatosensory
• outputs: motor results of planning –> behavior

Question 3

Ventral pathway: regions involved? nature of info? inputs? outputs?

Answer 3

• regions involved: temporolimbic regions
• nature of info: emotional
• inputs: limbic & somatosensory
• outputs: behavior or visceral

Question 4

Focused attention

Answer 4

• there is constant reflexive attention–> need to suppress this to be able to focus on something else
• the dorsolateral frontal cortex plays a role in this
• average adult can sustain attention for 50 min

Question 5

Reflexive attention

Answer 5

• constant attention system going on from the occipital, parietal and temporal cortexes
• constantly attending to the environment

Question 6

Focused visual attention

Answer 6

-attention to visual stimuli is initiated in the frontal eye fields (superior to broca’s area)–> sends info to the parietal cortex which has a spatial map –> sends signal to superior colliculi to cause goal directed visual scanning

Question 7

Stroop effect

Answer 7

• shows a conflict btwn different sources of info
• ex. the word “blue” written in a yellow color
• this is used to test focused visual attention

Question 8

Impairment in the attention system

Answer 8

• results in what appears to be short term memory loss
• as we age we start losing the ability to pay attention
• you cant remember what you dont pay attention to

Question 9

Wokring memory

Answer 9

• allows you to store info no longer present in the envi for a short period of time: verbal, visual/spatial, facial images. objects
• can manipulate or transform this info to guide behavior
• on average you can store 8-9 bits of info at a time here
• usually assessed using a delayed response
• the frontal cortex plays a role in the “delay” period
• info is stored in the parietal cortex

Question 10

Visual working memory

Answer 10

• center is in the right dorsal frontal cortex

- circuit needs to be intact for an image to remain in short term memory

Question 11

Spatial working memory

Answer 11

• where we store info about our surroundings
• impossible to separate visual/spatial memory from spatial memory b/c that relies so much on our visual input
• found anterior to the frontal eye fields

Question 12

Verbal/object working memory

Answer 12

• we remember objects better if they have a name
• necessary for analytical reasoning (so found superior to it)
• found anterior to broca’s area –> which makes sense

Question 13

Analytical reasoning

Answer 13

• used to manipulate visual/object working memories

- ex. both used for solving puzzles

Question 14

Orbital frontal cortex

Answer 14

-communicates btwn the ventromedial and the dorsolateral cortex

Question 15

Ventromedial cortex

Answer 15

• primary role = social processing
• interpretation of emotion occurs here
• lots of connections with the limbic, hippocampus, and nucleus accumbens

Question 16

Hippocampus & the ventral pthwy

Answer 16

-part of the ventral pathways b/c emotion plays a role in making events memorable

Question 17

Insula & the ventral pthwy

Answer 17

• part of the ventral pathway
• plays a mjr role in taste
• connected to the stomach
• in lower animals it is necessary to make emotion-food-memories
• in humans it causes a visceral response to emotion

Question 18

4 Functions of the ventral tracts that deal with the executive fctns of the cortex

Answer 18

1. ability to use cues to predict future rewarding or adverse events
2. ability to be flexible and change one’s path in response to changing envi conditions
3. autobiographical memory = being able to sequence events
4. olfactory processing –> related to empathy/emotion

Question 19

Wisconsin card sorting test

Answer 19

• cards have various number of shapes and colors on them
• ask them which of the 4 cards matches with one on top of the pile
• tell the pt they are right no matter what they pick
• then after a few times tell them they are wrong
• once they make a new pattern tell them they are right again
• repeat
• test their ability to make changes to their pattern = flexible

Question 20

Occipitofrontal region

Answer 20

• primary task is to integrate the emotional info from the ventromedial cortex with the logical info from the dorsolateral cortex
• when this is damaged a person has trouble making decisions

Question 21

What are the 4 different kinds of awareness?

Answer 21

1. basic = info about your general physological (emotional) state
2. info about your abilities and disabilities –> lack of this = anosognosia
3. info about hunger, thirst, and body temp
4. info about self esteem and self image

Question 22

Sx of lesions in the left side dorsolateral PFC

Answer 22

-depression like sx

Question 23

Sx of lesions in right side dorsolateral PFC

Answer 23

-mania and risk taking

Question 24

Sx of lesions to orbitofrontal cortex

Answer 24

-impaired decision making

Question 25

Sx of lesions to the ventromedial cortex

Answer 25

-obsessive compulsive behavior