Frontal Lobes Flashcards
What are the functions of the Frontal Lobes
Diverse range of functions including:
motor control;
language production;
higher order cognition, including executive function
What is the Tertiary area of the Frontal Lobe
prefrontal cortex
What is the Secondary area of the Frontal Lobe
pre-motor cortex
What is the primary area of the Frontal Lobe
motor cortex
What most differentiates us from the remainder of the animal kingdom
the functions of the prefrontal cortex
The largest association area is the…
prefrontal lobe
what does the Medial Prefrontal Cortex / Anterior Cingulate do
Motivational mechanisms
Inititive
what does the Orbitofrontal Prefronal Cortex do
Inhibitory control
Personality
Emotional Intelligence
Integration of amygdala information and visceral information into contextually appropriate responses
what is Executive functioning
Umbrella Term
inter-related processes that are responsible for goal directed, purposeful behaviour
Highest cognitive state of the brain
Includes emotional and social behaviour
Just about every day to day activity is goal directed and requires executive functioning
What does the Dorsolateral Prefrontal Cortex (DLPFC) do
Mediates cognitive function / executive functioning
Organization of information to facilitate a response
WHat are three areas of Executive Function effected by DLPFC
Working Memory
Abstraction
Perseveration
What is some Evidence of Prefrontal Damage
Perseveration Absence of Abstract thought Failure to utilise errors Unable to plan and learn via feedback Difficulty in focusing and sustaining attention. Lack of insight into their own problem
How do DLPFC lesions effect thinking
concrete thought or knowledge predominates and abstract thought or knowledge is limited.
what controls Executive functioning
Dorsolateral Prefrontal Cortex (DLPFC)
What is Working memory
Ability to hold information in mind for a short period of time in order to achieve a particular goal or purpos
What does working memory involve
memory + executive function
Which regions are important for manipulating working memory content
Dorsolateral
Which regions are important for memory maintenance
Ventrolateral
What are some Measures of working memory
Weschler Memory Scale
Digit span forwards – memory capacity
Digit span backwards – manipulation
N back is highly sensitive to age effects
Abstraction of rules is impaired in patients with deficits in what area
DLPFC
What are some Psychometric tests of planning and problem solving
Mazes such as the Porteous maze
Visuoconstructive abilities such as Block Design test and Rey Complex Figure
Problem solving behaviours
If patients display an inability to utilise their errors, in order to improve performance they suffer deficits in what area
DLPFC
What skills do maze solving tests require
planning capacity, pre-rehearsal or a mental act of rehearsing before performing the action
DLPFC can understand instructions but can’t…
evaluating the errors they make and learn from them
What skills does the Tower of London (and Tower of Hanoi) require
planning, monitoring performance and the ability to utilise errors
What are some tests of Visuoconstructive impairments
Block Design test from the Wechsler Adult Intelligence Scale (week 3).
Rey Complex Figure
Why is there repetition of earlier units that had already been copied in the Rey Complex Figure test
because the patient loses track of what has already been drawn because of a disorganized plan and/or an inability to monitor responses.
Patients with what lesions do poorly on visuo-constructive tasks such as Block Design or Rey Complex Figure
frontal lobe lesions or parietal lesions
Using a Visuoconstructive test how can you tell if the patient has frontal lobe lesions or parietal lesions
A DLPFC patient will display evidence of impaired planning, task monitoring etc but their perception of spatial relations should be in tact. Give them a plan, e.g. “let’s start with the big box first” and their performance will improve.
Parietal lobe patients will not improve with a plan as their perception of spatial relations will still be impaired (e.g. they will not perceived that a bunch of parallel lines are evenly spaced)
Why will DLPFC patients have difficulty with complex multi-step maths problems
will have difficulty breaking down these multi-step problems into doing one step at a time.
Rigidity of thought and an inability to shift set are clearly demonstrated in performance of which test
Wisconsin Card Sorting Test
DLPFC patients performing the Wisconsin Card Sorting Test display preservation - what does this mean?
patients may sort the cards appropriately by one category (e.g. colour), but when the psychologist changes the rule on the patient, they show difficulty shifting set so that they can sort the cards by a different category. Instead, they may continue to sort by the original category.
frontal lobe patients appear to have intact speech but closer examination sometimes reveals what
verbal perseveration.
In general these patients can repeat isolated words or very simple sentences
But if you give them a sequence of words to say, e.g. “cat, forest, house”, and then change the sequence to “cat, house, forest” then they tend to perseverate on the earlier order.
What patterns can be detected in the speech of a frontal lobe patient?
a lack of initiative in answering questions
lack of spontaneity
answering questions with elements of the question
What are the three areas of the Frontal Lobe
- prefrontal cortex
- premotor cortex
- motor cortex
What does the DLPFC link to
limbic system
thalamus
What are five functions of Executive Function
- decision making
- planning
- anticipation
- goal selection
- monitoring task performance and utilising feedback
The Trail Making test is a test of…
Executive Function
The Digit Span Test is a test of…
Working Memory
The Digit Span Backward Test is a test of…
manipulaing Working Memory
The N Back Test is good for what?
testing the point of memory deficit
Differences between Digit Span forward and backward suggest what?
problem with manipulation
Having to identify a rule is a test of what?
Abstraction
Abstraction is a function of what area?
DLPFC
Planning, problem solving, reacting to feedback all involve what general ability
Abstraction
Repeating an error even though you know it’s wrong indicated damage to what
Frontal Lobe
DLPFC
The Porteous Maze Test involves what functions
planning
rehersal
error evaluation and feedback
What does difficulties with spatial components of Rey Test indicate
Parietal damage rather than Frontal Lobe
Rigidity of thought is also called
Perseveration
Repeating the same words indicates
Perseveration
What is a good test of Perseveration
Wisconsin Card Sort
Wisconsin Card Sort utilises
set shifting
error utilization
Poblems of Verbal Fluency indicate damage to what
DLPFC
What are 2 tests of verbal fluency
FAS
Category Test
Which is more reliant on executive function - FAS or category
category
errors on tests as a result of impulivity indicate damage to what
Orbitofrontal PFC
Lack of empathy indicates damage to what
Orbitofrontal PFC
Lack of spontenity indicates damage to what?
Medial PFC
If you can respond to cues/external environment but not internal drivers what does this indicate
damage to Orbitofrontal PFC
What would you use the NEO to test
Orbitofrontal PFC
What is it important to know whe using the NEO to test Orbitofrontal PFC damage
premorbid function
What are the 3 areas of the Pre Frontal Lobe
Dorsolateral
Orbitofrontal
Medial
apathy and lacl of inititive indicate damage to what
Medial PFC
lack of spontaneous movement and verbalization indicate what
damage to Medial PFC
The PreMotor Cortex controls what
initial motor function
learning new movement
The primary motor cortex controls what
execution of movement
interference in execution of movement indicates damage to what
primary motor cortex
automatic movement is controlled by
Supplemantary motor area of premotor cortex
primary motor cortext creates movement by what
- excitation of its neurons,
- sends signal through the thalamus,
- then through the brainstem (where the signal is modified by cerebellar inputs)
- then down the cortico-spinal tracts of the spinal cord
- ultimately exciting particular muscles.
Topographic organisation occurs where
Primary Motor Cortex
what’s going to happen if I have a blood clot (i.e. stroke), preventing blood supply to the mid-lateral aspect of my left motor cortex?
right arm movement effected
Motor function occurs as a result of a circuit between what
the Frontal Cortex - Basal Ganglia - Thalamus and Cerebellum.
Basal Ganglia are a bunch of 5 nuclei that can excite or inhibit the thalamus. In turn, the thalamus is made up of many nuclei that can excite or inhibit the premotor cortex
What are the secondary areas of the Frontal Cortex
Premotor Cortex and Supplementary Motor Area
Inability to combine movments is a result of
Lesions to secondary motor areas
