Executive Function
What are Executive Functions?
In this youtube video, Dr. Adele Diamond talks about Child Development and the Brain - Insight to Help Every Child Thrive. She explains the role of executive functions in our lives.
http://www.youtube.com/watch?v=MQ_j1mjGLow
The key brain areas involved in executive function, the frontal lobes and in particular the prefrontal cortex, are among the last brain regions to mature. They continue to develop beyond adolescence and into adulthood.
The processes of executive functions are all related to how we manage ourselves and our resources in order to achieve a goal. It is an umbrella term for the neurologically based skills involving mental control and self-regulation.
Executive Functions are a set of higher order process tasks that include inhibition, working memory, shifting flexibly, planning, organizing and self-monitoring.
Scientists who study conscious control often refer to it as “executive function. Executive function has been linked to the business of making decisions and carrying them out, for example, trying to solve a problem.
Thinking about executive function in the context of problem-solving is revealing because it shows that executive function can be broken down into subfunctions. That is, in order to deliberately solve a problem, one needs to do several smaller things, in a specific sequence:
- Represent the problem: “What do I need to accomplish? What is preventing me from accomplishing it?”
- Come up with a plan for a solving the problem.
- Actually execute or carry out that plan.
- Evaluate the adequacy of the attempted solution.
Inhibition is considered a foundational skill. It starts during infancy when a child can delay eating a treat. It dramatically improves from ages 3 - 5, and the first leap in attaining inhibition appears in the preschool years. Age 4 seems to be a transitional period for the development of inhibitory control. A 4 year old can show simple inhibition (Luria’s hand game, Dimensional Change Card Sort DCCS, the Marshmallow Test). This is the time that a child is beginning to understand rules. Inhibition improves from ages 5-8 years, particularly for tasks that combine inhibition and working memory, but also at later years, especially with computer tasks but there are less dramatic changes.
Working Memory - By age 6, the executive component of working memory is sufficiently developed to be used during complex tasks that require coordination of the working memory components. There are linear increases in working memory from the ages of 4 - 14 years, and a levelling off between the ages of the 14 and 15 years old across all tasks. Working memory and attentional control undergo rapid development during the preschool years and have a substantial impact on children’s developing “approaches to learning” and corresponding academic achievement (Blair, 2006; Diamond,Barnett, Thomas, & Munro,2007) Working memory and attentional control play a key role in supporting emergent literacy and math computation and problem solving skills ( Fuchs et al,2005; Passsolunghi, Vercelloni & Schadee,2006; Swanson & Sachse-Lee, 2001).
Shifting is the ability to shift between mental states, rule sets or tasks. There appears to be a need for inhibition and working memory processes for shifting. At age 3-4 years old, the child can successfully shift between 2 simple response sets in which rules are placed in a story context or when demands on inhibition are reduced ( e.g. in a simple version of WCST; preschoolers can determine what a teddy bear's favourite shape is based on feedback and then after a set shift they can decide what a second teddy bear's favourite colour is based on differing feedback.) Shifting is unrelated to working memory and inhibition in preschoolers. The main improvement in set shifting occurs at ages 5 - 6 years old. Shifting reaches adult like levels at age 15. There is a linear improvement between ages 4 - 15.
Attentional skills, the ability to maintain or sustain attention on a particular subject as well as the ability to shift attention from 1 subject to another are positively related to both social-emotional and academic skills. Children with attentional disorders are more likely to have reading, language, and math deficits.
Many child friendly EF tasks are leading to a better understanding of the development of Executive Function. Children’s EF scores show major changes between ages of 4-6. Studies have shown that individual differences in EF before the start of school predicted both school readiness and children's success in numeracy and literacy. Helping children make gains in EF across the transition to school may have widespread benefits for children's behaviour, their self-concepts and their academic achievement. Soci-economic disadvantage, stress, low levels of cognitive stimulation, neglect and trauma all impact delays in Executive Function development.
Deficits in Executive Function can have major negative consequences on academic and social competence and have been implicated in a number of developmental disorders in childhood including ADHD and Autism.
References:
Blair, C., & Diamond, A. (2008). Biological processes in prevention and intervention: The promotion of self-regulation as a means of preventing school failure. Development and Psychopathology, 20(3), 899-911
Blair, C., & Razza, R. P. (2007). Relating effortful control, executive function, and false belief understanding to emerging math and literacy ability in kindergarten. Child Development, 78(2), 647-663
Passolunghi, M. C., Vercelloni, B., & Schadee, H. (2007). The precursors of mathematics learning: Working memory, phonological ability and numerical competence. Cognitive Development, 22(2), 165-184