Set of processes which allow us to control thoughts and actions
Goal directed
Important aspects in the definition
- Executive function (EF) is a function / ability sustained by various mechanisms and processes
- Effortful processes (as opposed to automatic processes)
- Top-down processes (modulating low-level, bottom-up processes)
- Goal-directed processes (linked to the individuals’ intention)
- Acts on thoughts and actions
Situations where the processes are used:
- Novel situations
- Situations requiring flexibility
- Not used in everyday automatic behaviour
HISTORICAL PERSPECTIVE
Alexander Luria:
The frontal lobe is essential for controlling and regulating behaviour (brain damaged patients during the
war)
We still think now that the PFC is important but other regions also play a role (parietal, subcortical)
Peak EF development during ages 4 -7: supported by many studies
Many tests used today are inspired by the tests he created
BOUNDARIES
EF at the frontier between Working Memory (WM), Attention and Self Regulation
WORKING MEMORY AND EF
Baddeley
Maintaining the goal of the task
Maintaining information and resisting interference from distracting information
Maintaining information and manipulating information
As opposed to maintaining passive information
ATTENTION AND EF
Posner
Endogenous attention (Top-down, conceptually driven)
Exogenous attention (Bottom-up, stimulus driven)
EF:
Selective attention
Divided attention
Voluntary shifts of attention
As opposed to alertness or stimulus driven orienting (pop out effects)
, SELF REGULATION AND EF
Effortful control / emotion regulation
More emotional component : controlling behaviour and emotions
“hot” EF as opposed to “cold” cognitive control
TASKS USED TO ASSESS EF
GENERAL PRINCIPLES:
A task requires:
- Non-automated processes
- A novel solution (problem of familiarisation with the task)
Often a costs is measured whereby the performance is compared across two conditions
- Condition without cognitive control (baseline) (rules out difficulties with lower level processes)
- Condition with cognitive control
STROOP TASK
Read names of colours written in different colours
Word is read automatically so cognitive control is needed to inhibit reading response
But what if you can’t read? Is it appropriate for children?
VARIATIONS ON THE STROOP TASK:
Simon Task : red and green responses, red and green targets on screen
- If red target appears on the same side as red response - fine
- If red target appears on the same side as green response, have to inhibit pressing the button
underneath it and look at the colour
Luria Tapping task: do the opposite number of taps as the experimenter
- Have to inhibit automatic response to mimic
Flanker task: which way is the middle fish facing?
- Congruent: all facing the same way
- Incongruent : middle fish facing different way
Day / Night task: say the opposite of what you see
GO / NO GO TASK
See numbers, if red numbers press red, if green letter press green
Build up that response
Then if you see a letter, don’t press
See colour before you realise it’s a letter so have to inhibit response
75% go trials, 25% no go - to build up automatic response to colour
For children - bear and dragon, do what the bear says but not what the dragon says
WISCONSIN CARD SORTING TASK
Tricky for young children
So developed the Dimensional change card sort (DCCS) for children
Colour game / shape game