Week 9 - Executive Function Flashcards
A 3-year old is sitting in front of a laptop. Her first task is to press the left arrow key when she sees a circle on the screen and the right arrow key when she sees a triangle. After 5 minutes of doing this task, she is given a second task. Here, the situation is reversed as she needs to now press the left arrow key when she sees a triangle and the right arrow key when she sees a circle.
The 3-year old is able to do this without a problem which means she has intact ______.
a. Attentional inertia
b. Extradimensional shifting
c. Intradimensional shifting
d. Inhibitory control
c.Intradimensional shifting
Executive function: the concept
Definitions
DEFINITIONS
● Executive Functions refer to those mechanisms by which performance is optimised in situations requiring the operation of a number of cognitive processes (Robbins, 1995)
● Executive Functions refer to complex cognitive processing requiring the coordination of several subprocesses to achieve a particular goal (Elliott, 2003)
● Executive Functions are the high-level cognitive processes that facilitate new ways of behaving, and optimise one‘s approach to unfamiliar circumstances (Gilbert & Burgess, 2008)
Executive function: the concept
Planning & Organisation
● Goal Setting
● Prioritization
● Action initiation & inhibition
● Setting & following action sequences
● Action Flexibility in changing situations
● Interference control & self-correction
● Impulse Control & Emotional Regulation
● Control of Attention
● Cognitive Flexibility
● Problem Solving & Decision Processes
Norman and shallice’s theory
Supervisory attentional system (SAS)
● All routine action plans are saved as Schemas
● Activation of a Schema – leads to the running of an Action
● The Responsible System is Contention Scheduling
● Routine action plans run automatically
Attentional control is neccesary for controlled action plans
● This is the Supervisory Attentional System (SAS)
● Situations that are new, unknown or dangerous
● Tasks, that require planning or decision making or searching for failures
● The SAS
a) Has limited attentional resources
b) Can control action plans via the selection of schemas
Inhibitory control
The ability to control one’s attention, behavior, thoughts, and/or emotions to override a strong internal predisposition or external lure, and instead do what’s more appropriate or needed.
●Without inhibitory control we would be at the mercy of impulses, old habits of thought or action (conditioned responses), and/or stimuli in the environment that pull us this way or that.
●Thus, inhibitory control makes it possible for us to change and for us to choose how we react and how we behave rather than being unthinking creatures of habit.
● Inhibition of automatic / prepotent responses
Stroop Task
Inhibition of automatic / prepotent responses
Hayling Task
Response Initiation
Provide an appropriate word to complete a sentence from which the last word was missing:
e.g. The captain wanted to stay with the sinking
e.g. The captain wanted to stay with the sinking SHIP.
Response Inhibition
Provide a word which makes no sense at all in the context of the sentence from which the last word was missing:
e.g. Most cats see very well at
e.g. Most cats see very well at BANANA.
Inhibition of automatic / prepotent responses
Go/No-Go Task
Working memory
●Holding information in mind and mentally working with it or working with information no longer perceptually present
●Working memory is critical for making sense of anything that unfolds over time, for that always requires holding in mind what happened earlier and relating that to what comes later.
●Reasoning would not be possible without working memory. We need it to understand written and spoken language.
●Allows us to bring conceptual knowledge and not just perceptual input to bear on our decisions, and to consider our remembered past and future hopes in making plans and decisions
Temporarily holding and manipulating information in
short-term memory service of goal-directed action
N-back task
Delayed matching to sample task
Digits backward task
Cognitive flexibility
This builds on working memory and inhibitory control and comes in much later in development
●The ability to change perspectives spatially (e.g., “What would this look like if I viewed it from a different direction?”) or interpersonally (e.g., “Let me see if I can see this from your point of view”).
●To change perspectives, we need to inhibit (or deactivate) our previous perspective and load into working memory (or activate) a different perspective.
●Another aspect of cognitive flexibility involves changing how we think about something (thinking outside the box).
VERBAL FLUENCY
● Produce as many words as you can from a given category.
(Semantic Fluency: Words that belong in the category Animals)
(Phonemic Fluency: Words beginning with the letter G)
Set shifting
Flexibility when faced with changing schedules or reinforcement
WCST: Wisconsin Card Sorting
Subjects sort the cards following a criterion (Colour, Form, Number)
● They obtain feedback after each trial of sorting a card into a chosen pile
● Classification criteria is suddenly changed without warning
(after 10 correct sorting trials)
Previously correct rule must be inhibited
● Flexibility is necessary to change the rule
● Current rule must be maintained
● Frontal lobe patients make perseverative errors!
● Perseveration: Repetition of words or gestures after they have ceased to be relevant or appropriate
Brixton task
● Previously correct rule must be inhibited
● Flexibility is necessary to change the rule
● Current rule must be maintained
● Frontal lobe patients make perseverative errors!
IED/ DCCS TASk
Previously correct rule must be inhibited
● Flexibility is necessary to change the rule
● Current rule must be maintained
Children (3 yr) make no errors with intradimensional shifts
Children (3 yr) make errors with extradimensional shifts
- ATTENTIONAL INERTIA -
Planning, problem solving & reasoning
Tower of London task
Multiple errands task
Development of executive functions
Studying the development and maturation of this ability over the lifespan aids the understanding of healthy & impaired function
●Childhood Adolescence Early Adulthood
ANTISACCADE (AS) TASK: Inhibitory Control
– Suppression of competing, goal-irrelevant information –
The rate of response inhibition failures in an AS task decreased with age, with intersubject variability remaining constant with age
(b)Activation in the DLPFC decreased until adolescence, when it reached adult levels, whereas activation in the dACC increased with age through adolescence
Central executive network (CEN)
Cognitive control network. Task positive network
The fronto-parietal task control network responsible for higher-level cognitive functions, including the control of attention and working memory
KEY AREAS
(i) lateral prefrontal cortex (dorsalateral - DLPFC)
(ii) dorsal anterior cingulate (dACC)
(iii) posterior parietal cortex
(iiii) basal ganglia (striatum: putamen, nucleus accumbens)
(v) cerebellum
Symptoms: frontal lobe lesions
● “Stereotyped Behavior“ (Luria, 1973)
● Repetitive, aimless, unsuitable actions
● Utilization behavior (Lhermitte, 1983)
● Stimulus-driven stereotypical reactions
● Errors of perseveration / attentional inertia
The Case of Phineas Gage
● Dysexecutive Syndrome Symptoms:
oSocially inappropriate behavior oPersonality changes oDisinhibition oImpulsivity oInability to plan for the future oInability to follow rules
Frontal Lobe: Classification of Symptoms
● Motor (precentral)
o Voluntary motor behavior
● Sensory/Perceptual symptoms
o Taste (hedonic response to food)
o Smell
o Flavour
● Cognitive (prefrontal) oSpontaneous Behavior oPlanning/Strategy Formation oAttention oUtilization Behavior oMemory: Encoding & Retrieval oMemory: Implicit & Explicit oMemory: Autobiographical/Episodic oWorking Memory
Frontal Lobe: General Functions
●Mediate the ability to engage in abstract thought
●Allow planning and organization of behaviour logically and temporally
●Inhibit inappropriate social and emotional responses
Dorsolateral PFC
oConceptual Reasoning
oSpatial Reasoning
o“COLD COGNITION”
Ventromedial PFC/Orbitofrontal Cortex
oBehavioural Self Regulation
oReward & Emotions processing
o“HOT COGNITION”
Problems of self-control
Impulsivity:
The tendency to act prematurely and without foresight,
despite adverse consequences
Compulsivity:
A trait in which actions are persistently repeated,
despite adverse consequences
IMPULSIVITY ->
Poor motivational control
oOrbitofrontal Cortex (OFC) / Ventromedial PFC oNucleus Accumbens (N. Acc)
●COMPULSIVITY ->
Poor motor control
oPremotor Cortex (PMC)
oPutamen (Put)
