Higher Cortical Function - Constantinidis - Exam 1

Question 1

• The cortex contains unimodal and multimodal (=multi-sensory) processing areas
  
  • “___-____” areas integrate information from multiple senses—these are key for higher cognitive function, not tied to processing of sensory info from one sense
  • frontal heteromodal (heteromodal cortex refers to a region that receives input from multiple sensory or multimodal areas.
  • Two major areas of heteromodal cortex are generally identified) association cortex (prefrontal cortex) + lateral parietal and temporal heteromodal association cortex

Answer 1

• The cortex contains unimodal and multimodal (=multi-sensory) processing areas
  
  • “Multi-sensory” areas integrate information from multiple senses—these are key for higher cognitive function, not tied to processing of sensory info from one sense
  • frontal heteromodal association cortex (prefrontal cortex) + lateral parietal and temporal heteromodal association cortex

Question 2

• Language– a prototypical cognitive function
  
  • Language is:
    
    • Both localized and distributed– is localized to parts of the brain but these areas are distributed all around the brain

___ are language deficits resulting from brain damage.

___ are diagnosed according to the patient’s ability to express language.

Answer 2

• Language– a prototypical cognitive function
  
  • Language is:
    
    • Both localized and distributed– is localized to parts of the brain but these areas are distributed all around the brain

Aphasias are language deficits resulting from brain damage.

Aphasias are diagnosed according to the patient’s ability to express language.

Question 3

What are the numbers and what is the blue shaded region around?

Answer 3

1- Wernickes

4. Brocas

All the blue shaded areas are all part of the multi-modal system. They all have something to do with language.

Question 4

What are the regions for?

What is the significant of area 4, and 5?

Answer 4

1. Brocas area - generating words
2. Wernickes - understanding words
3. Arcute - interconnects Broca’s and Wernicke’s areas
4. and 5. Supramarginal and Angular gyrus are important because they are part of the multi-modal association system that is involved with language procsesing.

Also, since the arcuate fasciales travel underneath the supramarginal and angular gyrus, if you get localized lesions there, most likely you will also get damage to the arcuate fascicles (which normally connects Brocas and Wernickes to each other).

Question 5

T/F:

Localization of function in human brain is quite variable– Broca’s and Wernicke’s areas are NOT tied down to the same exact location in every person’s brain, when doing surgery, doctor must test each part of brain via electrical stimulation before proceeding. Therefore, mapping is required prior to epilepsy surgery.

Answer 5

TRUE

Localization of function in human brain is quite variable– Broca’s and Wernicke’s areas are NOT tied down to the same exact location in every person’s brain, when doing surgery have to test each part of brain via electrical stimulation before proceeding. Therefore, mapping is required prior to epilepsy surgery.

Question 6

Language processing displays cerebral dominance:

• ___ side – _____ of language, expression of substantive content
  
  • Most people are left hemisphere dominant for language
  • Broca’s and Wernicke’s areas are in the ____ hemisphere for 90% of people
• ___ side – comprehension of language, expression of emotional content, ___ (use of inflection and tone to convey meaning, aka not speaking like a robot)

Answer 6

Language processing displays cerebral dominance:

• LEFT side – comprehension of language, expression of substantive content
  
  • Most people are left hemisphere dominant for language
  • Broca’s and Wernicke’s areas are in the LEFT hemisphere for 90% of people
• RIGHT side – comprehension of language, expression of emotional content, prosody (use of inflection and tone to convey meaning, aka not speaking like a robot)

Question 7

Types of Aphasia

1. ___ : in the classical form, the patient is not fluent. The patient cannot speak, but can comprehend language. The person has no fluency, cannot repeat words, but comprehends.
2. ___ : the patient is not fluent, does comprehend, and is abe to repeat some words to some extent. This is a case that occurs when Broca’s area is intact, but there is a lesion in the multimodal motor areas around Broca’s area. We still need these areas to develop language, but because Broca’s is intact, the patient can repeat SOME words.
3. ___ – complete destruction of everything (both Broca’s and Wernicke’s are destroyed).
4. ____ - patients are fluent, can generate words, but the words they are generating are not logical. They speak a lot, but it does not make any sense. These patients are not able to comprehend language either, so when you speak to them, they will not be able to understand the content. Because of this, they cannot repeat words either.
5. ___ : patient is fluent, cannot comprehend, but has some ability to repeat words. This is not caused by a lesion in Wernicke’s area itself, but a lesion in the transcortical sensory areas AROUND Wernickes (which again, is necesarry to comprehend lanaguge). However, even though these regions are lesioned, Wernicke’s and Broca’s are still intact, so the patient can repeat SOME words.
6. ___ : patient is not fluent, cannot comprehend, but still has the ability to repeat words because their Broca’s and Wernicke’s areas are still intact (they can hear and repeat the word). This is the case when someone has simltaneous damage to the transcortical motor and sensory association areas. Broca’s and Wernicke’s are still spared, so patient can still hear and repeat the word.
7. ___ - Patient has fluency, has comprehension, but cannot repeat words. The damage is at the arcuate fasciculus. The patient cannot repeat words bceause Broca’s and Wernicke’s is disconnected
8. __ ___ - Patient is fluent, comprehends and can repeat words. It is possible to have a very localized lesion. Patient has the general language function, but if you test them they have some difficulty naming things (orange example on youtube).

Answer 7

Types of Aphasia

1. Broca’s Aphasia : in the classical form, the patient is not fluent. The patient cannot speak, but can comprehend language. The person has no fluency, cannot repeat words, but comprehends.
2. Transcortical motor lesions: the patient is not fluent, does comprehend, and is able to repeat some words to some extent. This is a case that occurs when Broca’s area is intact, but there is a lesion in the multimodal motor areas around Broca’s area. We still need these areas to develop language, but because Broca’s is intact, the patient can repeat SOME words.
3. global aphasia – complete destruction of everything (both Broca’s and Wernicke’s are destroyed).
4. Wernicke’s aphasia - patients are fluent, can generate words, but the words they are generating are not logical. They speak a lot, but it does not make any sense. These patients are not able to comprehend language either, so when you speak to them, they will not be able to understand the content. Because of this, they cannot repeat words either.
5. Transcortical sensory aphasia : patient is fluent, cannot comprehend, but has some ability to repeat words. This is not caused by a lesion in Wernicke’s area itself, but a lesion in the transcortical sensory areas AROUND Wernickes (which again, is necesarry to comprehend lanaguge). However, even though these regions are lesioned, Wernicke’s and Broca’s are still intact, so the patient can repeat SOME words.
6. Mixed transcortical aphasia : patient is not fluent, cannot comprehend, but still has the ability to repeat words because their Broca’s and Wernicke’s areas are still intact (they can hear and repeat the word). This is the case when someone has simltaneous damage to the transcortical motor and sensory association areas. Broca’s and Wernicke’s are still spared, so patient can still hear and repeat the word.
7. Conduction aphasia - Patient has fluency, has comprehension, but cannot repeat words. The damage is at the arcuate fasciculus. The patient cannot repeat words bceause Broca’s and Wernicke’s is disconnected
8. Anomic aphasia - Patient is fluent, comprehends and can repeat words. It is possible to have a very localized lesion. Patient has the general language function, but if you test them they have some difficulty naming things (orange example on youtube).

Question 8

Aphasias:

___ – complete destruction of everything

___– BA and WA spared, but hight function/comprehension disrupted

___– good comprehension (since that’s WA), but can’t repeat words. They have understanding of their condition, know what they hear and can process it but can get out the words

____– “dynamic aphasia,” lesion in anterior superior frontal lobe, usually speak one or two word sentences, severely impaired writing ability

____– can’t comprehend but can speak fluently, will just keep talking but may be nonsense (think they’re making sense but they really aren’t)

___– multisensory cortex damaged around WA but WA itself is preserved

___– lesion of connection between areas, can speak and understand but can’t repeat

____– everything checks out (they’re fluent, can comprehend, and can repeat) but still have something going on

• Ask open ended questions to tease out the problem, may not be immediately evident
• Test patient with uncommon words

Usually result of very small focal lesion

Answer 8

Aphasias:

Global– complete destruction of everything

Mixed transcortical– BA and WA spared, but hight function/comprehension disrupted

Broca’s– good comprehension (since that’s WA), but can’t repeat words

Have understanding of their condition, know what they hear and can process it but can get out the words

Transcortical motor– “dynamic aphasia,” lesion in anterior superior frontal lobe, usually speak one or two word sentences, severely impaired writing ability

Wernicke’s– can’t comprehend but can speak fluently, will just keep talking but may be nonsense (think they’re making sense but they really aren’t)

Transcortical sensory– multisensory cortex damaged around WA but WA itself is preserved

Conduction– lesion of connection between areas, can speak and understand but can’t repeat

Anomic– everything checks out (they’re fluent, can comprehend, and can repeat) but still have something going on

• Ask open ended questions to tease out the problem, may not be immediately evident
• Test patient with uncommon words

Usually result of very small focal lesion

Question 9

Blood supply to language areas is provided by a combination of the ____ and ___ arteries into a “____” area

____ mostly supplied by MCA superior division

____ mostly supplied by MCA inferior division

These areas a re a common source of language deficits as a result from ___.

Answer 9

Blood supply to language areas is provided by a combination of the ACA and MCA arteries into a “watershed” area

BA’s mostly supplied by MCA superior division

WA’s mostly supplied by MCA inferior division

These areas a re a common source of language deficits as a result from stroke.

Question 10

Other language related conditions have variable causes, including damage to visual, attention, or motor brain areas

• ____– inability to read
• ____– inability to write
• ____– is a ____ language defecit, NOT a brain anatomical abnormality. This entails haing difficulty reading words correctly, having deficits in phonological processing during reading (ex. can’t combine phonologic and visual aspect of words)

Answer 10

Other language related conditions have variable causes, including damage to visual, attention, or motor brain areas

• Alexia– inability to read
• Agraphia– inability to write
• Dyslexia– is a DEVELOPMENTAL language defecit, NOT a brain anatomical abnormality. This entails haing difficulty reading words correctly, having deficits in phonological processing during reading (ex. can’t combine phonologic and visual aspect of words)

Question 11

Question: a 50 year old male presents with impaired fluency, intact comprehension and impaired ability to repeat words. When asked any question, he always responsd with a single word: “Hodor.”

Damage to which cortical area is the most likely cause of this patient’s pattern of impariment?

Answer 11

Question: a 50 year old male presents with impaired fluency, intact comprehension and impaired ability to repeat words. When asked any question, he always responsd with a single word: “Hodor.”

Damage to which cortical area is the most likely cause of this patient’s pattern of impariment?

This patient has Broca’s Aphasia.

Question 12

Attention– directed/selective thought, associated with the ____ lobe

Behavioral consequences of attention– enhances detection and recognition, speeds reaction time, is the gateway to memory

Neural substrates of attention– ___ ___ CORTEX (most importantly), but also ____ cortex and subcortical structures (___ nucleus of thalamus and ____colliculus)

Answer 12

Attention– directed/selective thought, associated with the parietal lobe

Behavioral consequences of attention– enhances detection and recognition, speeds reaction time, is the gateway to memory

Neural substrates of attention– posterior parietal CORTEX (most importantly), but also prefrontal cortex and subcortical structures (pulvinar nucleus of thalamus and superior colliculus).

“Pay attention to the substidute teacher, ms. Corwin, otherwise the superrior intentdent will pulvaiize your PF!”

Question 13

Neglect is the flip side of attention– the ____ ____ lobe is dominant for spatial attention. This is different from language. Where is language localized?

Answer 13

Neglect is the flip side of attention– the RIGHT parietal lobe is dominant for spatial attention.

Remember– Language is Left, attention is right (and each hemisphere is responsible for the opposite side’s function)

Question 14

Explain each picture (red part indicates the lesion)

Answer 14

Question 15

____ sided stroke = severe attention defecit leading to severe LEFT neglect.

___ sided stroke = minimal RIGHT neglect

The most severe attentional distortion, is caused by a ____ parietal lesion.

Answer 15

Right sided stroke = severe attention defecit leading to severe LEFT neglect

Left sided stroke = minimal RIGHT neglect

The most severe attentional distortion, is caused by a posterior parietal lesion.

Question 16

Neglect is NOT purely a sensory syndrome.

If you have a focal lesion in your primary visual cortex, and you have a specific part of the visual cortex that is destroyed, you will never be able to see anything. Neglect, in contrast, does not affect visual acuity in the ability to detect details. That is, in patients that have neglect, once you can get them to detect a visual stimulus, they will have normal visual acuity, and will be able to recognize, process, classify, and understand what is going on on their left. With neglect, they have difficult orienting their attention to the left side. Once the patient detects the visual stimulus, they have normal visual acuity and are able to detect details

The deficit of neglect is much more pronounced when ____ stimuli are present simultaneously on both sides and compete for attention, called “____.” One example is holding two fingers in front of a patient with neglect. The left side will be lost.

The deficit does NOT involve only the left side of visual field, but also left side of ___ presented entirely in the right visual field. The example is the drawing. If a patient is asked to draw a clock, they will only draw the right side of clock.

Answer 16

Neglect is NOT purely a sensory syndrome.

If you have a focal lesion in your primary visual cortex, and you have a specific part of the visual cortex that is destroyed, you will never be able to see anything. Neglect, in contrast, does not affect visual acuity in the ability to detect details. That is, in patients that have neglect, once you can get them to detect a visual stimulus, they will have normal visual acuity, and will be able to recognize, process, classify, and understand what is going on on their left. With neglect, they have difficult orienting their attention to the left side. Once the patient detects the visual stimulus, they have normal visual acuity and are able to detect details

The deficit of neglect is much more pronounced when two stimuli are present simultaneously on both sides and compete for attention, called “extinction.” One example is holding two fingers in front of a patient with neglect. The left side will be lost.

The deficit does NOT involve only the left side of visual field, but also left side of object presented entirely in the right visual field. The example is the drawing. If a patient is asked to draw a clock, they will only draw the right side of clock.

Question 17

Conditions associated with parietal damage:

• ___ ___– inability to copy a drawing or put together parts of an object
• ____– denial that left side of body belongs to them, will think their arm is someone else’s
• ___ – pt doesn’t realize/understand they have a deficit, and their brain spontaneously comes up with an explanation (____) for the deficit (the pt may be agitated)

Answer 17

Conditions associated with parietal damage:

• Constructional apraxia-- inability to copy a drawing or put together parts of an object
• Asomatognosia– denial that left side of body belongs to them, will think their arm is someone else’s
• Anosognosia – pt doesn’t realize/understand they have a deficit, and their brain spontaneously comes up with an explanation (confabulation) for the deficit (the pt may be agitated)

Question 18

Diffuse neurotransmitter systems– diffusely projecting systems that regulate arousal and attention

• Characteristics:
  
  • Widespread projections from a single nucleus
  • Do NOT respect cytoarchitectonic or functional boundaries
  • Slow transmitters (neuromodulators)
  • Regulate “___” rather than transmit specific information– increase or decrease activity of large parts of brain

There are FOUR of them: NADS

Answer 18

Diffuse neurotransmitter systems– diffusely projecting systems that regulate arousal and attention

• Characteristics:
  
  • Widespread projections from a single nucleus
  • Do NOT respect cytoarchitectonic or functional boundaries
  • Slow transmitters (neuromodulators)
  • Regulate “states” rather than transmit specific information– increase or decrease activity of large parts of brain

There are FOUR of them: NADS

Norepi

ACh

Dopamine

Serotonin

Question 19

_____

• Produced in the locus coeruleus and the lateral tegmental area– responsible for sending NE to entire cortex
  
  • Diffuse terminal fields throughout forebrain
• Clinical significance– alertness/attention, aggression, memory, depression
  
  • Responsible for dramatic/traumatic memory formation, ex remember where you were on 9/11/2001
• Called adrenaline from the neck down

The locus coeruleus is a nucleus in the located in the ____, and is involved with physiological responses to stress and panic.

The locus coeruleus is the principal site for brain ____ of norepinephrine (noradrenaline).

Answer 19

Norepinephrine

• Produced in the locus coeruleus and the lateral tegmental area– responsible for sending NE to entire cortex
  
  • Diffuse terminal fields throughout forebrain
• Clinical significance– alertness/attention, aggression, memory, depression
  
  • Responsible for dramatic/traumatic memory formation, ex remember where you were on 9/11/2001
• Called adrenaline from the neck down

The locus coeruleus is a nucleus in the pons (part of the brainstem) involved with physiological responses to stress and panic.

The locus coeruleus is the principal site for brain synthesis of norepinephrine (noradrenaline).

Question 20

Acetylcholine

• Produced in the __ ___. When we talk about the _ __, it includes the:
  
  • Septal nuclei
  • __ __ of Broca
  • and most importantly, the __ __ (of Meynart).

Clinical significance of ACh– arousal, attention, “drowning out” the noise (the volume control of the brain)

Important in ____ disease – early stages specifically involve death of __ __, so loss of Ach production; first line of treatment is __ __ inhibitors to increase Ach in the synapse

Answer 20

Acetylcholine

• Produced in the basal forebrain. When we talk about the basal forebrain, it includes:
  
  • Septal nuclei
  • Diagonal band of Broca
  • and most importantly, the nucleus basalis (of Meynart).

Clinical significance– arousal, attention, “drowning out” the noise (the volume control of the brain)

Important in Alzheimer’s– early stages specifically involve death of nucleus basalis, so loss of Ach production; first line of treatment is acetylcholine esterase inhibitors to increase Ach in the synapse

Question 21

Dopamine

• Produced in the ___ ___ area and __ ___. Dopamin is especially important in ___ areas and the ____ cortex

Dopamine targets the: __ __, __ and the __ ___.

Clinical significance of dopamine: reward, schizophrenia, Parkinson’s and drug addiction.

In ___ disease, there is death of neurons in the VTA and SN. This reduces the amount of dopamine, which causes an inability to initiate movement (rigidity, tremor, etc) in addition to cognitive problems.

​Treatment for this disease?

• Give ____, a precursor to dopamine
• But, if you give too much, you see changes in behaviors which depend on the pre-frontal cortex. For example: extramarital affairs, gambling, crazy investments (exciting events become irresistible). Why? because the dopamine stimulates the pre-frontal cortex and the limbic system, increasing risk-seeking behavior.

Dopamine is also important in drug addiction– disregulation of dopamine.

In schizophrenic patients, dopamine is not regulated appropriately.

Answer 21

Dopamine

• Produced in the ventral tegmental area and substantia nigra. Dopamine is especially important in limbic areas and the prefrontal cortex

Dopamine targets the: frontal cortex, striatum and the limbic system.

Clinical significance of dopamine: reward, schizophrenia, Parkinson’s and drug addiction.

In Parkinson’s disease, there is death of neurons in the VTA and SN. This reduces the amount of dopamine, which causes an inability to initiate movement (rigidity, tremor, etc) in addition to cognitive problems.

​Treatment for this disease?

• Give L-Dopa, a precursor to dopamine
• But, if you give too much, you see changes in behaviors which depend on the pre-frontal cortex. For example: extramarital affairs, gambling, crazy investments (exciting events become irresistible). Why? because the dopamine stimulates the pre-frontal cortex and the limbic system, increasing risk-seeking behavior.

Dopamine is also important in drug addiction– disregulation of dopamine.

In schizophrenic patients, dopamine is not regulated appropriately.

Question 22

Serotonin

• Produced in the __ __
• Clinical significance in – mood, food intake, and depression.
  
  • Associated with eating disorders

Answer 22

Serotonin

• Produced in the raphe nuclei
• Clinical significance– mood, food intake, depression
  
  • Associated with eating disorders

Question 23

Higher cognitive function – controlled by ___ cortex, which is larger in human proportional to body than any other animal

Answer 23

Higher cognitive function– controlled by prefrontal cortex, which is larger in human proportional to body than any other animal.

Question 24

___ cortex:

Function: “executive functions”

• planning
• inhibition
• concentration and orientation
• judgment
• language
• abstract thinking
• mood

Pathology: frontal lobe lesion

• seen with trauma and frontal lobe dementia
• presents with a lack of social judgment, change in personality, and lack of motivation
  e. g. Phineas Gage

Ways to test?

Answer 24

Pre-frontal cortex:

Function: “executive functions”

• planning
• inhibition
• concentration and orientation
• judgment
• language
• abstract thinking
• mood

Pathology: frontal lobe lesion

• seen with trauma and frontal lobe dementia
• presents with a lack of social judgment, change in personality, and lack of motivation
  e. g. Phineas Gage

You can test by the Stroop Test,,

asking things like, “How are __ and __ alike?”

Word generation task: Name as many words as possible starting with the letter F in 60 seconds.

Question 25

Localization of general intelligence = ___ \_\_\_ cortex Deficits after prefrontal damage: I-PAWS

Answer 25

Localization of general intelligence = **lateral prefrontal** cortex Deficits after prefrontal damage: I-PAWS * Impulsiveness/disinhibition * Perseveration-- lack of cognitive flexibility * Apathy (lack of interest) * Working memory (STM) * Shifting cognitive set