Executive Function Disorder and ADHD

In order to start your day, you get up with the goal of getting ready for work. During this process, you start to plan out your day in your mind as you think about your schedule. On your way to work, you might flip through radio stations and be forced to deal with new construction that affects traffic patterns and delays your arrival. When you finally arrive at work, your boss comes up and hands you a new project due at the end of the day. But, you roll with it.

The ability to complete these tasks requires the use of skills and mental processes that together are described as “executive function.”

During his presentation on the third day of the 2013 NEI Psychopharmacology Congress, David W. Goodman, MD, director of the Adult Attention Deficit Disorder Center of Maryland, Lutherville, Medical Director of Suburban Psychiatric Associates, LLC., Amherst/Orchard Park, NY, and assistant professor in the Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of Medicine, revealed that executive function is primarily involved in a number of key cognitive processes and is directly responsible for the correct response to inhibition, mental flexibility, planning, set shifting, working memory, and interference control. While the tasks and actions such as those described in the introduction are done almost by second nature by the general population, executive function (EF) is impaired in certain individuals, resulting in executive dysfunction (ED).

Up to 10 percent of the general population actually has executive dysfunction, according to Goodman. On its own, this can have a negative impact on quality of life. This effect is exacerbated when executive dysfunction occurs in individuals who have a disorder that already impairs functioning, specifically a disorder such as ADHD. As researchers are learning, when this occurs, it significantly impairs those with ADHD in terms of executive and non-executive functioning, and produces neuropsychological deficits that have been shown to persist even into adulthood. In fact, Goodman noted that research supports the theory that EF in childhood correlates with a wide range of negative effects later in life, such as expulsions or suspensions from school and lower reading scores. It has also been shown to have a negative effect on employment status as an adult.

Tests such as those associated with measuring inhibition and interference, working memory, fluency, and planning and problem solving tasks can measure EF. However, Goodman reminded the audience that while studies have shown, “abnormal scores on measures of EF are generally predictive of the diagnosis (ADHD); normal scores cannot rule out diagnosis.”

This was one of the key issues Goodman touched on during his presentation. He believes that simple “cold” testing (during which participants sit in a quiet room to take the test) cannot fully evaluate an individual with ED; to gain a full picture of the disorder, patients should be tested in a real world setting with distractions. Goodman listed several real-world tests developed by researchers that can give clinicians more effective measures of ED by requiring patients to make decisions and perform tasks that are more reflective of those that confront them during their activities of daily living, such as multitasking in a city test, the multiple errands test, executive secretarial tasks, and the “virtual supermarket” and “virtual library” tests.

Goodman said clinicians should not assume a patient with ED must also necessarily have ADHD. While ED raises the likelihood of a diagnosis of ADHD, it’s not a guarantee. It’s simply something clinicians should be aware of when treating patients with ADHD. Moreover, Goodman said that clinicians should be aware that increasing the dose of ADHD medication will not necessarily fix symptoms of ED in patients.