The term executive functions refers to the higher-level cognitive skills you use to control and coordinate your other cognitive abilities and behaviors. The term is a business metaphor, suggesting that your executive functions are akin to the chief executive that monitors all of the different departments so that the company can move forward as efficiently and effectively as possible. How we organize our lives, how we plan and how we then execute those plans is largely guided by our executive system.
Executive functions can be divided into organizational and regulatory abilities. Organization includes gathering information and structuring it for evaluation. Regulation involves evaluating the available information and modulating your responses to the environment. Seeing a wonderful dessert in front of you may be tempting to devour, but your executive system might remind you that eating it would conflict with your inner goals, such as losing weight.
- Organization – attention, planning, sequencing, problem-solving, working memory, cognitive flexibility, abstract thinking, rule acquisition, selecting relevant sensory information
- Regulation – initiation of action, self-control, emotional regulation, monitoring internal and external stimuli, initiating and inhibiting context-specific behavior, moral reasoning, decision-making
Anatomy of Executive Functions
Executive deficits have been associated with damage to the most forward areas of the frontal lobes (located just above your eyes), as well as the cortical (i.e., parietal lobes) and subcortical structures that connect to the frontal lobes. The executive system involves the prefrontal cortex, basal ganglia and thalamus.
The frontal lobes are the last areas of the brain to fully develop. This area of the brain was evolutionarily late to appear and is much larger in human beings than in our closest nonhuman primate relatives. The frontal lobes typically account for about 40% of the human brain.
Disorders of Executive Functions
Because these skills integrate information at a higher level across cognitive domains, damage to the executive system typically involves a cluster of deficiencies, not just one ability. The loss of that administrative control affects the ability to organize and regulate multiple types of information and often causes behavioral change.
Damage to the executive system often leads to:
- Difficulty organizing
- Difficulty in planning and initiation (getting started)
- Inability to multitask
- Difficulty with verbal fluency
- Trouble planning for the future
- Difficulty processing, storing, and/or retrieving information
- Mood swings
- Lack of concern for people and animals
- Loss of interest in activities
- Socially inappropriate behavior
- Inability to learn from consequences of past actions
- Difficulty with abstract concepts (the inability to make the leap from the symbolic to the real world)
- Unawareness or denial that their behavior is a problem
Assessment
The instruments used to assess executive behavior draw on the cognitive skills described above, such as mental agility, planning, organization, inhibition, and freedom from distraction. Widely used tests include the Word Fluency Task, Stroop Test, Wisconsin Card Sorting Tes,t and the Trail Making Test.
Executive function deficits can occur as the result of a variety of neurologic conditions, including traumatic brain injury, neurodegenerative diseases including frontotemporal dementia, cerebrovascular disease, as well as a number of psychiatric and developmental disorders, including obsessive-compulsive disorder, Tourette’s syndrome, depression, schizophrenia, attention-deficit/hyperactivity disorder, autism, and addiction.
