Neuropsychology of Executive Function Flashcards
What are executive functions?
Controlling mechanisms of the brain, required for goal-directed behaviour, adaptive responses to novel situations, and regulation of emotion and behaviour
Give examples of executive functions.
▪️Planning
▪️Initiation
▪️Organisation
▪️Inhibition
▪️Problem solving
▪️Self monitoring
▪️Error correction
▪️Cognitive flexibility
What are the two broad categories of clinical executive dysfunction?
▪️Classical ‘cognitive’ executive change
▪️Wider changes involving emotion, social cognition, and reward response
What is the single process model of EF?
All EF processing occurs in the central executive
What is the multiple process theory of EF?
Executive functions comprise of a number of distinct components working together
e.g., sensory perceptual systems, trigger data base, contention scheduling, supervisory attentional system)
What is the supervisory attentional system?
▪️ Proposed action schemas - programmes for the execution of routine behaviours
▪️ Activated automatically in response to environment
▪️ SAS allows for inhibition of automatic responses and activation of appropriate action schema in non-routine situations
What processes are necessary for the SAS?
- Top-down control of action schemas (GDB)
- Monitoring of behaviour
- Specification of a memory trace required for GDB)
- Establishment of future intentions (goal planning, PM)
What can TBI tell us about executive dysfunction?
▪️ No unitary prefrontal syndrome - instead dissociable processes
▪️ Lesions remote from frontal cortex can also cause executive symptoms/failure
According to Stuss and Alexander, what are the three systems of attentional control?
▪️ Superior medial (energising, initiating/sustaining)
▪️ Left lateral (task setting)
▪️ Right lateral (monitoring)
What are the ventromedial and orbitofrontal cortices involved in?
Emotional and behavioural regulation
What are the frontopolar areas associated with?
Integrative/meta-cognitive functioning
What have fMRI and PET studies of EF found?
▪️ Activation is not specific to location nor task
▪️ Generally increases over whole PFC as any task becomes more complex
What is the only cognitive task that is SPECIFIC to dominant frontal lobe function?
Phonemic fluency
What are the main principles to considering when assessing EF?
▪️ Not exclusively frontal lobe function
▪️ Wide heterogeneity of prefrontal areas implicated in different tasks that can change with subtle manipulation
▪️ Frontal lobes mainly about the self
▪️ Multiple processes involved, more dissociation than association
▪️ No problem with test does not mean no problem at all
What is Struss et al’s three-factor model of executive tasks/skills?
- Energisation (process of initiation or sustaining responses, e.g., apathy)
- Task setting (e.g., planning, organising, learning new task)
- Monitoring (e.g., checking, staying on task)
What does the controlled oral word association test/phonemic fluency task assess?
Initiation and perseveration
What is the modified six elements task of the BADS?
▪️ Test of multi-tasking and time organisation
▪️ 10 mins to complete some of 6 tasks
▪️ 2 dictations tasks, 2 arithmetic, 2 picture-naming (A and B)
▪️ Cannot do parts A and B together
What is the Action Programme subtest of the BADS and what does it assess?
▪️ Get the cork out the tube with the water
▪️ Problem-solving
What might influence performance on neuropsychological assessment?
▪️ Language
▪️ Culture
▪️ Socioeconomic status through education, occupation, segregation, exposure to violence
What are the main limitations of standard tests in detecting executive and social cognitive problems?
▪️ May not detect change in premorbidly high-functioning individuals
▪️ Doesn’t mimic stress of everyday life
▪️ More sensitive to DLPFC deficits than OFC
▪️ Social cognitive deficits may dissociate from classical executive skills
What supplementary information can you use to assess social cognitive deficits?
▪️ Informant report
▪️ Informant standardised measures (e.g., DEX-R, BADS)
▪️ Social cognitive tasks (e.g., reading mind in eyes)
▪️ Experimental tasks (e.g., IGT, CGT)
▪️ Structured behavioural assessment schedules (e.g., multiple errands)
What are the three main social cognitive skills?
▪️ Theory of mind
▪️ Emotion recognition
▪️ Judging/modifying social behaviour with change in context (faux pas tests)
What is the social situations task?
▪️ 20 vignettes of social situations
▪️ Rate 1 or 2 behaviours in context of each vignette (from fairly normal to shocking behaviour)
What can the Iowa gamble task and Cambridge gamble task be used for?
▪️ Assess decision-making under ambiguity and risk and reward-based cognition
▪️ Particularly sensitive to VMPFC/OFC dysfunction in presence of intact performance on executive tasks in substance misuse, MS, and bipolar
What is EMOTICOM?
A battery of tests developed to evaluate emotion, reward/motivation, impulsivity, and social cognition
Useful to measure treatment-related change across these domains that may affect QoL, carer burden, and distress
How might the frontal paradox be evident in the multiple errands task?
Very deficient performance in those with frontal lobe damage despite intact performance on pencil-paper executive tasks
