We all have challenging tasks we want to complete. Partly that's because finding and maintaining the mental energy required is so difficult. Interruptions can feel constant. Distractions can always seem just a moment away.

Getting started is hard. Restarting, once interrupted, is harder. Staying the course once under way?

That can be really hard.

In general terms, people who tend to get things done possess more of what neuroscientists term cognitive control: the mental function that allows you to connect your plans and goals with your actions.

In short, why you sometimes don't get important things done.

And, more important, how you can. 

That's the focus of Dr. David Badre's book On Task: why we struggle to stay focused on tasks, even ones we enjoy and really want to complete. Why we put off working on tough tasks, and turn to easy "wins" like checking off quick to-do items. 

How can you exercise greater cognitive control -- and in the process accomplish more of the things that really matter to you? 

Free up chunks of time

Say you need to solve a difficult problem, one that requires mentally sifting through a variety of data, knowledge, and options. (In neuroscience terms, the aggregate is called a "task set.") 

The tougher the challenge, the less likely you can hold that task set in your working memory. Especially if you're constantly interrupted. Or distracted. Plus, there's a switching cost; every time you focus on something else, the process of "resetting" yourself on that task requires significant mental energy and resources.

The more time you can free up, and the more you can minimize distractions and interruptions, the better the outcome. 

And if you can't finish, try to keep the environment the same the next time you focus on that task. According to Badre, since memory retrieval is affected by context, working on a task in the same contextual environment could aid retrieval and help you to more quickly reestablish your task set.

In this case, familiarity breeds productivity.

Gather what you need ahead of time

Some people see preparing to work on a huge task as a sort of "priming" ritual: The act of gathering tools, gathering information, setting up their actual or virtual workspace -- those actions help settle and ground them. 

If that's you, keep doing it.

Odds are, though, that's not you.

While your "prep time" may feel like an accomplishment in itself, all the tidying and straightening and preparing only serves to keep you from focusing on what you actually need to accomplish. 

And reduces the total amount of mental energy you have available.

Instead, prep ahead of time. Ideally, the night before. Make a list. Make some notes. Review information. Gather the materials you need.

Prime yourself to hit the ground running -- because a mind in efficient motion tends to stay in efficient motion.

Don't multitask

I know. We all think we're good at multitasking, even though considerable research shows we really aren't. (Some studies even say multitasking actually makes us stupid.)

When you're working on a difficult task, attempting to multitask reduces the amount of working memory available for the task that matters. Instead of giving it your all, you can only provide a fraction of your brainpower to the challenge -- in spite of the fact that it might feel like you're (mentally) working extremely hard.

So focus on just one thing.

And to make sure you can, turn off notifications. Shut down your email. Put your phone away. Do the best you can to make sure you're undisturbed.

Because the cost of multitasking -- the cost of switching -- is a cost you can't afford.

Develop -- and Stick With -- a Process That Works for You

I like to tackle my most important task first. (The first thing you do in the morning is often the most important thing you will do since it sets the tone for the rest of the day.)

Maybe you're at your problem-solving best when you take a walk. Maybe pen and paper works better than a device when you brainstorm. Maybe you are most effective when you get up early, or stay up after everyone else is in bed.

The key is to find a routine, a process, or a structure that allows you to be as productive as you can be. So don't just analyze outcomes; take a step back and analyze the process you use to achieve outcomes. That way, you'll develop and refine a system that works for you.

Which will be an investment in productivity that pays off for years to come.

Because, as neuroscientific research shows, the key to achieving huge goals is having the skill to execute an action -- as well as optimizing your focus, task control, and working memory capacity.

And to accomplishing the things you really want to accomplish.