"She's extremely good and efficient at completing her homework or school project if she's interested in the subject matter," a friend said about her 12-year-old daughter, "but then, after all that hard work, she'll forget to actually bring it to school if I don't step in, I'd say nine times out of 10". She went on: "Of course, if she's not interested, her brain simply switches off! Her locker at school is an absolute mess all of the time, and her room? I'm afraid to even go in there. If I ask her to tidy up or put the laundry away, she'll say she'll do it, only to either forget or somehow find herself unable to do it. It's not defiance. It's not that she doesn't want to do it. It's a real struggle, but it sure can be frustrating!"
This child was diagnosed with ADHD and the difficulties my friend observes are executive functioning issues. That's been quite the buzzword lately. If you hang around parenting forums of Facebook groups, especially those targeted at parenting children with certain disorders, including ADHD, you'll have heard the term.
What Is Executive Functioning?
Executive function is a rather broad concept that encompasses a person's ability to plan ahead, keep things organized, initiate and complete tasks (and in a timely manner, too!) and regulate your own behavior. These essential skills involve many different parts of the brain — the prefrontal cortex, caudate nucleus, and subthalamic nucleus among others — and cover quite a few different areas [1, 2]:
- Working memory.
- Inhibitory control.
- Cognitive flexibility.
- The ability to monitor the quality of your own performance.
- The ability to initiate tasks.
- The ability to organize things.
These overlapping, complementary, areas come together to enable people to engage in a multitude of everyday tasks that are still developing in children , but come quite naturally to most adults.
A well-functioning working memory will allow you to retrieve information from your brain and write it down, for instance, or read an instruction manual and then put together your new piece of IKEA furniture. Inhibitory control, which includes impulse control, prevents you from blurting out the first thought you have, or from eating those two cupcakes when you're on a diet. Cognitive flexibility allows you to accept and respond to change, by trying a second solution if the first one didn't work, for instance.
It's thanks to executive function skills that most people understand approximately how long a task will take to complete, plan what needs to be done, actually do those things, and finish the task before the deadline. It's also thanks to executive functioning that most people are able to filter out background noise and listen only to the person they were talking to. 
Quite impressive when you think about it, right? Working memory alone involves to very distinct processes, namely the ability to store information and the ability to use that knowledge to take action . If you've never had any issues in your day-to-day functioning, you may never have thought about just how complex an average person's cognitive processes really are.
When you struggle with executive function, you may, struggle with all or some of the previously described processes.
What Causes Executive Functioning Disorder?
It's most likely that executive functioning deficits have a wide variety of causes. It is not currently even clear to what extent the frontal lobes of the brain are responsible for these deficits, with some research suggesting that the processes involved in causing executive dysfunction may be cognitive and behavioral, rather than a result of brain anatomy . It has, however, been associated with a variety of other disorders.
Rather a few different studies found that executive functioning is significantly impaired in people with ADHD (and ADD, the same thing without the "hyperactive" component), and some have even proposed executive functioning weaknesses as the underlying cause of ADHD .
People on the autism spectrum are particularly likely to suffer from executive functioning deficits, finding it hard to plan, be flexible, multitask, quickly move from one task to another, or filter out stimuli that are irrelevant to the activity they're trying to engage in. Some studies suggest that executive dysfunction is, in fact, the origin of stereotypical autistic behaviors, like a great need for routines and repetition — to the point that it is one of the key signs of Asperger's in adults. 
I Think I Have Some Executive Functioning Deficits — What Now?
The first step is to have a word with your doctor, if your daily functioning is impaired enough that you feel you need it. Diagnosis is complex, since executive functioning encompasses so many different skills , but that doesn't mean your doctor cannot be helpful.
It'd be lovely if you could just pop a pill for that, hopefully without any side effects, but that's not the case, unfortunately. Stimulants and dopamine partial agonists/antagonists, such as risperidone and aripiprazole, have been used to manage such areas of executive function as attention and impulse control, but no medication or combination thereof has been found to improve all areas of executive functioning as of yet. 
Interventions that have been shown to increase executive functioning include:
- Computerized working-memory training.
- Aerobic exercise (really!).
- Mindfulness practice. 
Many people with executive functioning deficits also, anecdotally, greatly benefit from external systems that remind them to complete tasks. Whether you go for low-tech post-it notes or a partner reminding you to get that thing done, already, or high-tech options like setting alarms on your phone or computer, these reminders both, well, remind, and give you a little push in the back.