Tim Urban, founder of the blog Wait But Whyis no stranger to procrastination. Like many of us, he has never been able to shake this destructive habit, and there's a pretty big reason why--he has become a master at it.

In a recent TED talk, Urban describes the process of writing his 90-page senior thesis in college, an experience that would normally require months of planning. But then, "the funniest thing happened," Urban explains. Although Urban had a year to complete the paper, he found himself working down to the wire. After months of not writing a single word, Urban woke up one day with three days until the deadline, so he did the only thing he could:

I wrote 90 pages over 72 hours, pulling not one but two all-nighters--humans are not supposed to pull two all-nighters--sprinted across campus, dove in slow motion, and got it in just at the deadline.

The thesis was very, very bad.

And, today, Urban is a professional writer ... who still procrastinates. (A confession: I do too.)

To better understand his own behavior, Urban went straight to an MRI lab to study the brains of a procrastinator and a proven non-procrastinator.

The difference? "Both brains have a Rational Decision-Maker in them," Urban explains, "but the procrastinator's brain also has an Instant Gratification Monkey," something that, Urban says, compels a procrastinator to interrupt productivity to go on YouTube binges or procrastinate in other ways.

And, it turns out, many of us are at the mercy of this Monkey, which only cares about doing activities that are easy and fun, at the expense of success.

Urban then discusses the one thing that wakes us up to do work when a deadline gets too close--the Panic Monster--but he ultimately underlines the idea that staying aware of the Instant Gratification Monkey is a job for all of us, whether we self-identify as a serious procrastinator or not.

"We need to think about what we're really procrastinating on, because everyone is procrastinating on something in life," Urban warns. Long-term procrastination--much less visible and much less talked about than the funnier, short-term, deadline-based kind, he says--is suffered quietly and privately, resulting in a huge amount of long-term unhappiness.

Consider thinking harder on the goals and dreams you're really procrastinating on, before you run out of time. Are you going to make major moves to accomplish something big today, or will you save that for tomorrow?

My personal suggestion? Don't wait.