Executive Function of Brain
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Transcript of Executive Function of Brain
Executive Function
PresenterDr. Anusa A MFirst year MD PG
Prepared by Prof. Rooban T,
Oral & Maxillofacial Pathologist
Introduction
What is Executive Function
Unified term for cognitive processes that
regulate,
control,
manage other cognitive processes such as
planning, working memory, attention, problem
solving, verbal reasoning, inhibition, mental
flexibility, task switching and initiation and
monitoring of actions.
What is Executive Function ?
Is a theorized cognitive system in psychology that
controls and manages other cognitive processes.
Responsible for processes that are also referred to
as executive functions, executive skills, supervisory
attentional system, or cognitive control.
Definition
“The CEO of the Brain”Saltus, 2003
This description focus attention on the
increase in frontal lobe synaptic
connectivity that begins to occur during
adolescence, eventually leading to
developmental improvements in self-
direction and self-control - Stuss &
Alexander, 2000
Directive capacities of the human brain –
Goldberg, 2001
Definition
Definition
“There are specific processes related to different brain regions within the frontal lobes. There is no frontal homunculus, no unitary executive function”
- Stuss and Alexander (2000)
“Multiple executive functions that govern human conscious perceptions, feelings, thoughts, and actions as constituting a collection of “co-conductors” of an orchestra in a highly collaborative manner with the others”
Definition
The ability to
Shift from one concept to another
Modify behavior, particularly in response to new
or modified information about task demands
Synthesize and integrate isolated details into a
coherent whole
Manage multiple resources of information
Make use of relevant acquired knowledge Stuss, 1992
Definition
Ability to plan ahead and organize behavior across time and space in order to fulfill goals and intentions
The ability to shift strategies and adapt to changing circumstances
Planning, decision making, directed goal selection, and monitoring of ongoing behavior
Also involved in self-awareness, empathy, and social sensitivity
Temple, 1997
Definition
Gioia, Isquith, Guy, & Kenworthy (1996) on
defining Executive Functions:
A collection of processes or interrelated functions
responsible for
Guiding, directing, managing cognition, emotion
and behavior, particularly in novel
problem-solving situations
Purposeful, goal-directed problem-solving behavior
Definition
Denckla (2001) “Clinical Descriptors—EF Terms from Cognitive Psychology:”
Supra-ordinate (Higher Order) Processes Meta-cognitive or Metamodal Capacities Control Processes (Initiate, Sustain, Inhibit,
Shift)▪ Set Maintenance▪ Self-Monitoring and Flexibility▪ Inhibitory Processes
Integrative Processes Sequencing/Organizing Processes
Models of Executive functions
EF Models
Top-Down inhibitory control Model
Supervisory Attentional Model system – Norman & Shallice, 1986 and further expansions
Working memory Model- Baddley, 1996, 2002
Self regulatory Model
Problem solving Model
EF Models
Conceptual Model, Lezak
Neurophysiological Model, Barkley, 1997
Miller and Cohen Model, 2001
Holarchical Model – McCloskey, 2004
Miyake and Friedman’s Model
Cascade of control Model, Banich, 2009
Supervisory Attentional Model System
Norman & Shallice, 1986 –
ContentionScheduling
(3)
TriggerDataBase
Special-purposeCognitiveSubsystems (1)
PerceptualSystem
SupervisoryAttentional System (4)
SchemaControl Units
(Action)
(2)
Supervisory Attentional System
Shallice (1981)
Supervisory Attentional System
Supervisory Attentional Model System
Shallice and Burgess, 1996 – expanded further
Working Memory Model
Baddley, 1996 and 2002
Visual Semantics
Episodic LTM
Language
Neurophysiological model of Self regulation
Barkley, 1997
The McClosky Holarchical Model, 2004
Self Activation
Initiation and “ramping up” of basic
executive functions related to an awakened
state of mind and to overcoming sleep
inertia.
Self Regulation
A set of control capacities that cue and
direct functioning across the domains of
sensation/ perception, emotion, cognition,
and action
Self Realization
Directs cognitive processes that engage in self-
awareness, self-reflection and self-analysis.
Cues cognitive processes to access
accumulated information about self and apply
it in specific situations to initiate, sustain, or
alter behavior.
Self Determination
Foresight/Long-Term Planning and Goal Generation
Directs the use of cognitive processes to construct
visions of the future and plans for action over longer
periods of time.
Directs reflection on the past for purposes of
improving or altering behavior and thinking in future.
Self Generation
Pose speculative questions related to the meaning and
purpose of life and/or the ultimate source(s) of reality
and physical existence, mind-body relationships, spirit,
and soul; contemplates existence beyond the physical
plane.
Directs the generation of a philosophy of life used to
guide self-awareness, self-realization and the other levels
of executive function processes; serves as a basis for an
ultimate source of intentional behavior direction.
Trans-Self Integration
Directs the engagement of mental processes that
enable realization and experiencing of a trans-self
state of ultimate or unity consciousness.
In most spiritual traditions, this state is considered
the highest achievement of human consciousness
and therefore very different from the maladaptive
states characteristic of clinical diagnoses of
dissociative states.
IV. Self Generation
III. Self Control:
Self Determination
Goal Generation
II. Self Control: Self Regulation
Initiate
Modulate
Execute(BehaviorSyntax)
Focus Attn Sustain Attn MonitorCheck
Interrupt/Stop
Inhibit
Perceive Organize
Manipulate Store
Retrieve
I. Self Control: Self Activation
Mind-Body Integration, Sense of Spirit
Awaken, Attend
Anticipate
Hold Balance
Correct
Generate
Time Sense
Pace
V. Trans-self IntegrationSense of source, Cosmic consciousness
Sensation/Perception Cognition Emotion Action
Self RealizationSelf
AwarenessSelf
AnalysisLong-Term
Foresight/Planning
Gauge
Shift
Associate
Choose
Focus Effort Sustain EffortFlexible
Plan
Time Mgt
Cascade of Control Model
Unified concept of all existing models
Bannich et al., 2009
Three levels Neurobiological Psychological Computational
Cascade of Control Model
• Bias to task relevant process
Posterior DLPFC
Executive Function Development - Lines and Levels
EF development
Brain and EF
Arenas of Involvement for EF
Variations in types of activities affected by
EF is a key concept in understanding what
we refer to as the arenas of involvement
in which the effects of executive functions
are manifested.
4 key arenas
Arena Implication
Intrapersonal Control one’s own internal states
Interpersonal Interactions with others
Environment Interactions with the environment around them
Symbol system Engagement with the tools of the culturally derived symbol systems used to process and share information
Arena of interaction and EF
Internal command vs External demand
INTERNAL COMMAND
Executive control can stem from a person’s own internal desires, drives, aspirations, plans, and proclivities
Easier and Less effort
EXTERNAL DEMAND
Executive control summoned by sources outside of the person, executive control is being initially cued.
Tough, more effort
Domain Implication
Perception Executive control of modes of input including perception of external (sensory)and internal (representational) stimuli
Cognition Executive control of thoughts & thought processes
Emotion Executive control of feelings & emotional processes
Action Executive control of modes of output including behavior in external world and storage & retrieval of internal representations
Domains of functioning
Other Executive Function Assessment dimensions
Contextual factors
Factor Explanation Mental Stance Consciously directed vs. non
consciously convectedLocus of Intention Internally commanded vs.
externally demandedMaturation Chronological age and degree of
neural developmentBiological Constraint
Medical conditions
Contextual factors
Factor Explanation
Multi-Cueing
Capacity
Simultaneous vs. sequential ordering of
multiple EF capacities, multitasking, EF
“syntax”
Task
Constraints
Constraints on how information is
processed when performing a task
Generalizatio
n
Setting specific vs. setting nonspecific
Energy Executive control stamina fluctuations
Temporality Temporal nature of any observed stamina
fluctuations
Information processing capacities
Time frames for reference
Factor Explanation Immediate Initial registrationExtended Immediate Active working memoryRemote and recent past
Retrieval from long term store
Areas of Academic skill
Tests for EF Wisconsin Card Sorting Test
WCST; Heaton, Chelune, Talley, Kay, & Curtiss, 1993
Delis-Kaplan Executive Function System
D-KEFS; Delis, Kaplan & Kramer, 2001
NEPSY: A Developmental Neuropsychological Assessment
Korkman, Kirk, & Kemp, 1998
Behavioral Assessment of the Dysexecutive Syndrome
BADS; Wilson, Alderman, Burgess, Emslie, & Evans, 1996
Behavior Rating Inventory of Executive Function
BRIEF, BRIEF-2, BRIEF-SR; Gioia, Isquith, Guy, & Kenworthy, 2000
Frontal Systems Behavior Scale
FrSBE; Grace & Malloy, 2001.
Conditions with Executive Dysfunction
ADHD Conduct disorderDepressionBipolar disorderOCD Tourette syndromeHuntington's diseaseWilson's diseaseSchizophreniaAutismAsperger's syndromeNonverbal learning disordersTurner's syndromeFragile X syndrome
PhenylketonuriaFrontal brain tumorsTraumatic brain injuryAcquired brain injury, via toxins, anoxia, infections, etcComplex partial epilepsy of frontal originWilliams syndromeVelocardiofacial syndromeHydrocephalusFetal alcohol syndromeMetachromatic leukodystrophyCerebellar tumors
EF in AD/HD
Difficulties with the self- regulation cues of
Inhibit, Focus/Select, and Sustain.
Self-realization difficulties involving delayed
development of self-awareness, self-analysis,
long-term goal setting, and long term
foresight/planning
EF in Autism Spectrum disorder Include deficiencies related to
interpersonal arena.
Involve perception, emotion, cognition, action, difficulties with self-analysis and self-awareness
Severe deficits in self-determination
Decreased Fluency, Impaired Planning, Altered Flexibility
EF in ODD, CD
Multiple self-regulation and self realization
deficits.
Deficits are expressed in one arena of
involvement—the interpersonal arena—and
involve primarily the emotion and cognition
domains of functioning.
These difficulties are often accompanied by
difficulties with self-analysis and self-awareness
EF in Schizoprenia
Deficits include impairment in attention,
working memory and EF
Loss of verbal and visual learning and
memory, working memory, immediate,
selective and sustained attention,
perceptual/motor processing and motor
skills
EF in Schizoprenia
Amnesia, Loss of episodic memory only
Working memory and multi-tasking
impairments typically characterize the
disorder.
Deficits in response inhibition and
cognitive flexibility
EF in Parkinson’s disease
Problems with memory and thought
processes.
Increased distractibility
Problems in set formation and maintaining
and shifting attentional sets
Deficits in self-directed planning, problems
solving
EF in Parkinson’s disease
Working memory show deficits in the areas of: a) spatial working memory b) central executive aspects of
working memory c) loss of episodic memories d) locating events in time
EF in Fetal Alcohol Spectrum disorder
Decreased measures of planning ability, selective inhibition, concept formation and reasoning.
Decreased set-shifting, planning and strategy use, attention and spatial working memory, longer reaction and decision time
EF in Bipolar disorder
Problems of attentional processing, EF and verbal memory
Impairment in visual memory, working memory and risk taking behavior, selective attention, attentional shifting, verbal planning, verbal memory, perseveration
Loss of processing speed, inhibitory control, response inhibition and strategic thinking
Executive Functions
Plan actions towards a goal
Use information flexibly
Realize consequences
Draw inferences
Independent of IQ
EF and Brain
Function Capacity
Implicated Brain area
Self-Activation
Reticular activating system, epithalamus, caudate nucleus, anterior cingulate, dorsolateral cortex
Self-RegulationPerceive Prefrontal cortex, ventromedial
prefrontal, paracingulateInitiate Orbitofrontal cortex, anterior
cingulate; dorsolateral prefrontal cortex; superior medial
EF and Brain
Function Capacity
Implicated Brain area
Focus/Select Anterior cingulate; dorsolateral prefrontal cortex
Gauge Anterior cingulate, dorsolateral prefrontal cortex
Modulate Cingulate gyrus, orbitofrontal cortex, basal ganglia
Interrupt/Stop
Orbital prefrontal cortex, anterior cingulate, amygdale; right inferior frontal gyrus
EF and Brain
Function Capacity
Implicated Brain area
Inhibit Middle and interior frontal gyrus, orbitofrontal cortex, caudate, nucleus, basal ganglia, striatum; left superior frontal cortex
Sustain Dorsolateral prefrontal cortex, orbitofrontal cortex, thalamus, anterior cingulate
Hold Dorsolateral prefrontal cortex, anterior cingulate gyrus, left frontal cortex, anterior insula, frontal gyrus, cerebellum, hippocampus
EF and Brain
Function Capacity
Implicated Brain area
Manipulate Dorsolateral prefrontal cortexOrganize Dorsolateral prefrontal cortex Store Left prefrontal cortex, basal gangliaRetrieve Hippocampus, dorsolateral prefrontal
cortex, ventrolateral prefrontal cortexForesight/Plan
Dorsolateral prefrontal cortex, orbitofrontal cortex, striatum, hippocampus, cerebellum
Generate Left inferior frontal gyrus, bilateral frontal cortex and superior parietal lobes; dorsolateral prefrontal cortex; anterior cingulated
EF and Brain
Function Capacity
Implicated Brain area
Associate Left dorsolateral prefrontal cortex Balance Cerebellar-frontal pathway, anterior
cingulatedTime Orbitofrontal cortex Pace Basal ganglia, dorsolateral prefrontal
cortex; anterior cingulatedExecute Dorsolateral prefrontal cortex, interior
parietal, striatum,basal gangliaMonitor Dorsolateral prefrontal cortex,
anterior cingulate; right lateral prefrontal cortex
EF and Brain
Function Capacity
Implicated Brain area
Correct Dorsolateral prefrontal cortex, orbitofrontal cortex
Self-RealizationSelf-Awareness
Posterior cingulate or paracingulate sulcus, anterior medial and ventromedial prefrontal cortex, parietal region, left and right basal temporal regions, left orbitofrontal cortex, frontal gyrus, limbic and insula regions
EF and Brain
Function Capacity
Implicated Brain area
Self-Determination
Orbitofrontal cortex, ventromedialprefrontal cortex
Self- Generation
Medial frontal gyrus, posterior cingulate, angular gyrus, dorsolateral prefrontal cortex, anterior cingulated
Trans- Generation
Prefrontal cortex, anterior cingulate, reticular and middle thalamic region, basal ganglia, dorsolateral prefrontal cortex
Prefrontal Cortex and EF
PFC is a major area for EF to occur though other areas are involved
4 important functions involved Selective attention Working memory Preparatory set Monitoring
Perpetual Memory
Acquired through sensory organs.
@ basic level- memory of elementary sense perceptions, in sensory and parasensory cortices.
@ higher levels, multimodal sensory memories, in "trans-modal" cortex
@ higher cortex - includes episodic and semantic memories to form declarative memory.
The highest level is conceptual memory, form of perceptual knowledge.
Fuster J., 2003
Thank You
Declarative Memory
Declarative memory is conscious memory.
Knowledge of facts and events episodic (time-related data of past
experiences) semantic (fact-related) data.
Declarative memory stores information about facts (who, what, when, where) and the relationship between them.
“explicit memory” or “cognitive memory.”
Nondeclarative Memory:
That cannot be accessed consciously. Motor learning, habits, and conditioning. Includes skills achieved through repetitious
exposure Involves multiple senses , systems Utilizes multiple motor and cognitive
pathways in its execution. Other names “implicit memory,”
“dispositional memory,” or “nonconscious memory.”
Types of memory
Short term or Working Memory Long term memory - stored, permanent
information Semantic Memory - general information involving
who, what, why
Episodic Memory- information associated with time and place where memory was formed
Procedural Memory - stores information on how to do something
Perceptual Memory - serves to identify objects and structure of language; memory through senses
Short term or Working Memory Short lived; unprocessed; 3 phase - central executive, the visuo-
spatial sketchpad, and the phonological loop
Phyletic memory is a basic form of memory from primary sensory and motor cortices and foundation of individual memory
Executive memory is the representation of motor acts and behaviors