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Lo sviluppo delle Funzioni Esecu1ve
Lo sviluppo delle Funzioni Esecu1ve
• Execu1ve func1oning is very much aligned to our special gi;s as humans.
• When we talk about someone as being clever, it is almost always a comment about their crea1vity and their flexible problem-‐solving ability.
• We pride ourselves on our ability to adapt flexibly to the environment. We are also at 1me disappointed when we are deprived of our ini1ate an our ability to seemingly make our own decisions.
• Unlike other species (who run out stereotyped responses) we have many alterna1ves depending not only on the present circumstances but also on our es1mated future consequences of our ac1ons
Execu&ve func&oning is about adap&ng to changing circumstances in an independent and flexible way.
Some defini1ons . . .
• Execu1ve func1ons are intrinsic to the ability to respond in an adap1ve manner to novel situa1ons ... And can be conceptualised as having four components:
• 1) voli1on (capacity for inten1onal behaviour) • 2) planning • 3) purposive ac1on (the transla1on of an inten1on or plan into produc1ve, self-‐serving ac1vity requires the individual to ini1ate, maintain, switch and stop sequences of complex behaviour in an orderly and integrated manner)
• 4) effec1ve performance (Lezak, 2004)
Execu1ve func1ons are a collec1on of processes that are responsible for guiding, direc1ng and managing cogni1ve, emo1onal and behavioural func1ons, par1cularly during ac1ve novel problem solving (Gioia et al., 2000)
Some models ... • Baddeley and Hitch’s (1974) model of Working Memory used the unitary concept of the ‘Central Execu1ve’ as a supervisory cogni1ve process, presiding over the func1ons of the working memory system.
• Baddeley (1986) later suggested that his ‘Central Execu1ve’ be conceptualised in terms of the ‘Supervisory A]en1onal System’ (SAS) suggested by Norman and Shallice (1986).
However, execu1ve func1on has also been conceptualised as a collec1on of mul1ple, inter-‐related processes that func1on together as an integrated supervisory control system (Stuss & Alexander, 2000)
Anderson (2002) suggested a mul1-‐system model was
composed of four inter-‐related domains: a) Cogni&ve flexibility included skills of working memory,
divided a]en1on and u1lising feedback as a source of informa1on.
b) Goal Se3ng included conceptual reasoning, planning and strategic organisa1on.
c) A5en&onal control included selec1ve a]en1on, self-‐regula1on, inhibi1on and self-‐monitoring.
d) Informa&on processing included efficiency, fluency and speed of processing.
• Common across the various models and defini1ons, is the concept of execu&ve func&oning as a supervisory direc&ve system exer1ng regulatory control over other basic, domain specific neuropsychological func1ons, with the purpose of achieving a specified goal (Banich, 2009).
• The term ‘execu&ve func&on’ therefore refers to a complex set of cogni1ve abili1es, encompassing mul1ple processes that are involved in goal directed behaviour.
Corteccia prefrontale
• L’importanza delle FE emerge con lo studio dei veterani della II Guerra Mondiale
• Importan1 per il pensiero astra]o, di alto livello (competenze presen1 nell’adulto)
• A supporto di questo: studi anatomici che mostrano una maturazione di queste aree fino all’adolescenza.
• Si spiega così l’assenza di studi sullo sviluppo delle FE
FE e sviluppo
Misurazione: problemi e soluzioni
• Difficile definire opera1vamente FE: – il contrasto tra processi controlla1 ed automa1ci non è assoluto…ma i due poli sono gli estremi di un con1nuo
– Complessità dei compi1 per valutare FE* – Bassa corrispondenza tra processi e comportamento
Con i bambini potrebbe andare meglio….ma -‐ Limitazioni dovute al linguaggio
• Test di Stroop • FAS test di fluenza verbale • … Quindi i compi1 per testare le FE nei bambini devono essere molto semplici
Test per età evolu1va
• A. Luria (1966): – GO/ NO GO task
Test per età evolu1va
• A. Luria (1966): – Non verbal Stroop task: picture-‐based day/night task
Test per età evolu1va
• A. Luria (1966): – Fluency task: nomi appartenen1 alla stessa categoria seman1ca (animali, ves11..) piu]osto che nomi che iniziano con la stessa le]era
Test per età evolu1va
• A. Luria (1966): The hand game (control vs. conflict condi1on)
Corteccia prefrontale
Lo sviluppo delle FE
• 1) usando task appropria1 sappiamo ora che si sviluppano presto: es. PFC dorsolaterale so]ostante al compito piage1ano A non è B (a 12 mesi il bambino sa eseguire il compito)
• FE nei bambini si compongono delle stesse componen1 che negli adul1 (analisi delle componen1 principali, Welsh et al., 1991)
Birth -‐ 3 years • Move from infants who are reac1ve to everything in environment and easily distracted to a willful toddler with a goal in mind • EF begins to develop toward the end of the 1st year when “Object Permanence” develops • “An1cipatory Looking” and looking away from aversive s1muli are precursors to developing emo1onal control skills • 3-‐yr olds start to keep rules in mind & use them to guide their behavior. Can start to chose between 2 rules and guidelines 27
3-‐6 year olds should be able to….
• Preschoolers can begin to think about the past and plan for the future • S1ll difficult to have conscious control over emo1ons, despite knowing the “right thing” to do • Difficulty “choosing” to delay gra1fica1on or reward • Preschoolers start to be able to inhibit the less desirable choice • Follow 2-‐3 step direc1ons
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6-‐9 year olds should be able to….
• A]en1on becomes voli1onal • Able to handle delayed gra1fica1on • Develop beginning stages of problem solving (iden1fica1on, search for a cause, brainstorm solu1ons) – but frequently requires adult guidance for solving and preven1ng problems
• Completed development of “theory of mind” – perspec1ve taking skills
• Working memory significantly developing to hold up to 5-‐7 pieces of informa1on
• Can plan/sequence chores taking 10-‐15 minutes • Shi; mental sets/shi; a]en1on between mul1ple tasks
(Lucianna, 2003)
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9-‐12 year olds should be able to….
• Growth in verbal working memory skills • Able to select, shi; and maintain a]en1on sets • Able to reflect upon “hindsight” and developing foresight • Should be able to keep track of belongings away from home/school
• Self-‐regulate (behave when teacher out of the room, refrain from temper tantrum, refrain from rude comments)
• Reliably transfer materials to/from school • Keep track of scheduled ac1vi1es outside of school • Save money for a desired object, plan ways to earn money
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12-‐16 year olds should be able to….
• Help out with chores las1ng 30-‐60 minutes • Use a system taught to them for organizing assignments and homework. • Follow a complex school schedule with changing teachers and classrooms • Reliably es1mate the amount of 1me it will take to complete homework, chores, etc. • Inhibit rule breaking in the absence of visible authority
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16-‐20 year olds should be able to….
• Frontal cortex has a slow course of development – EF skills con1nue to develop into the mid-‐20’s • Should be able to formulate a long-‐term goal and steps needed to accomplish the goal. • Inhibit reckless and dangerous ac1vity and understand how this impacts their overall long-‐term goal
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