There is almost always a jigsaw puzzle in some stage of completion on my dining room table.

Sometimes I might complete the puzzle over a weekend, and other times it takes a few weeks.

I never feel pressure to finish a puzzle; I trust I will complete in time.

My brother-in-law Eric loves jigsaw puzzles too but insists on finishing the puzzle in a single sitting.

He gets crazy eyes, will gladly forgo sleep or food or the call of his bladder to complete a puzzle.

I always thought this was a charming idiosyncrasy.

Then I learned about Lithuanian psychologist Bluma Zeigarnik.

In 1920s Berlin, Zeigarnik noticed waiters seemed to remember multiple orders while the chefs prepared the food, but then completely forgot the orders once they had served them.

Zeigarnik delved deeply into studying how humans respond to unfinished tasks.

Turns out, not well; our brains crave closure.

Her research is now known as the Zeigarnik Effect, a phenomenon that describes the human tendency to feel stressed when we leave a task unfinished.

This “psychic tension” only abates once we complete our task and are satisfied with the results.

As long as we leave the task incomplete, our brain is in an uncomfortable position, and so the task takes center stage in our thoughts until we resolve the task.

If the ending is unsatisfactory, it will continue to bug us mentally until we fix it.

Had Eric discovered we were missing a puzzle piece when we neared the end of our undertaking, he would have been severely irritated.

That’s because each person demonstrates the Zeigarnik Effect uniquely.

What drives one person crazy doesn’t even occur to the next.

I am OK to leave a puzzle unfinished, but if David and I disagree about something, I can’t think about anything else until we resolve our conflict, spending my metal bandwidth to rehash what we already said and rehearse what I will say to bring the argument to a close.

My daughter feels the Zeigarnik Effect in the lure of Netflix binging.

Each episode of Riverdale or Stranger Things ends with a cliffhanger, and then seamlessly segues into the next episode.

The episode ends, but the story doesn’t.

This setup is by design; Netflix used the Zeigarnik Effect to create a seamless interface experience and encourage binge watching.

Writers compose “earworm jingles” on the same principle.

If the jingle is catchy, you’re more likely to sit through an otherwise dull commercial because your brain wants to hear the complete song.

David’s Zeigarnik Effect shows up when he is unsatisfied with the ending of a book or movie.

I remember when we watched the HBO series “The Sopranos;” the series finale left viewers up in the air.

Did Tony die? Did he survive? Why was “Don’t Stop Believin’” playing on the jukebox?

David felt cheated and talked about the finale for days; he was frustrated that there was no closure.

I couldn’t care less. I liked the idea that we could draw our conclusions about the fate of Tony Soprano.

I am both anticipating and dreading the end of “Game of Thrones;” if it doesn’t go David’s way, I’ll be forced to hear about it for weeks.

So how can we use this phenomenon to our advantage?

Well, it seems that interrupting a task makes it cement more firmly in your mind.

The longer you go before completing a task, the more neurons (or brain cells) you’re delegating to that task.

Over time, this helps to encode that information in your hippocampus, the part of the brain responsible for making, storing and retrieving memories.

Zeigarnik suggested the mere satisfactory completion of a task often leads to people forgetting it.

I think back to college math tests, where I crammed the night before without a break, took the test, and then promptly forgot everything I had “learned” about geometry the night before.

I imagine my brain metaphorically dusted its hands of the task, ready to move on to the next thing.

The take-away is to take breaks when trying to learn a new skill or complete a project.

Science suggests that for every hour you work, a five-minute rest will improve your efficiency and productivity when you return to your task.

Taking frequent breaks throughout your workday is a boon to your mental health.

Maybe leave this article on your boss’s desk Monday?

Erin Smith is the owner of the OM place in Winchester, the author of “Sensible Wellness” and the online host of the OM channel. Follow her on Twitter @erinsmithauthor.