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How the Little-Known Zeigarnik Effect Impacts Everyone Daily

Studies shed light on how unfinished tasks impact productivity.

Key points

  • The Zeigarnik effect occurs when the brain more readily recalls an interrupted task than a completed one.
  • Unfinished tasks create mental tension, it affects how well people perform other tasks in the meantime.
  • Studies show making plans improves productivity.
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The Zeigarnik effect isn't exactly what one might call a household name, despite the fact that it's quite common and often makes people incredibly unproductive. The effect is well known, however, to psychological professionals. What is it? It’s what occurs when the brain more readily recalls an interrupted task than a completed one. Bluma Zeigarnik was a Lithuanian-Soviet psychologist who discovered this effect.

Zeigarnik studied this recall phenomenon after her professor, Gestalt psychologist Kurt Lewin, noticed that a waiter remembered the details of still-unpaid orders better than those orders that had already paid. Zeigarnik performed a series of experiments to uncover the underlying reasons for this phenomenon. She first published her research in 1927 in the journal Psychologische Forschung.

Her research built upon one of Lewin's field theories that “a task that has already been started establishes a task-specific tension, which improves cognitive accessibility of the relevant contents. The tension is relieved upon completion of the task but persists if it is interrupted. Through continuous tension, the content is made more easily accessible, and can be easily remembered.”

The Zeigarnik Effect as a Study Aid

The Zeigarnik effect is a great tool when someone wants to memorize things. For example, the effect suggests that students who interrupt their study to perform unrelated activities (such as studying a different subject or playing a game), will remember material better than students who finish study sessions without taking a break. Therefore, a purposeful interruption that might seem like a waste of time when studying is in fact productive.

The problem with the Zeigarnik effect in terms of productivity is when it’s in operation for non-studying chores, such as creating and achieving new goals. Two researchers at Florida State University, E. J. Masicampo and Roy F. Baumeister, found in several studies that the mental tension created by unfinished tasks — what Lewin and Zeigarnik first recognized — persists to the point that it impacts how well people perform other tasks in the meantime. Essentially, unfinished tasks distract people from completing different new tasks.

Unfinished Tasks Decrease Productivity

Masicampo and Baumeister believed there was ample theory and evidence that unfulfilled goals persist in the mind, e.g., the Zeigarnik effect. They wanted to know whether this persistence caused distraction. It did. Their studies demonstrated that unfinished goals caused distracting thoughts and poor performance when study participants tried to achieve new goals. They found that the Zeigarnik effect immobilizes the brain’s various cognitive processes that usually promote goal pursuit. In a nutshell, unfinished tasks distract people, thereby making them less efficient going forward.

Masicampo and Baumeister further theorized that plan-making — writing out detailed to-do tasks for unfulfilled goals — could lessen the distracting impact of the Zeigarnik effect. Lo and behold, when they allowed participants to create specific plans for their unfinished goals before tackling new tasks, the various interference effects vanished. They found that committing to a specific plan for a goal likely not only facilitates achieving a goal but also frees up cognitive resources for other pursuits. Once someone creates a plan for an unfinished task, the brain suspends the cognitive activity related to attaining the unfinished task. The brain then resumes its goal-related cognitive activity at the planned future time.

Planning Isn’t Necessarily Writing a To-Do List

Planning seems to help the brain let go of the cognitive tension from unfinished tasks thereby creating room to accomplish new tasks, i.e., be more productive. To-do list zealots might take this as proof of concept. But that’s the wrong takeaway.

Daily to-do lists are not productive for everyone. There are those who swear by using to-do lists and religiously crossing every item off and then those who barely ever refer to theirs or create plans in their heads. What this research does mean is that creating detailed plans to accomplish goals, whether revisited or not, is helpful in relieving cognitive tension (stress) and achieving goals. These are two incredibly productive and worthy outcomes, no matter how one prefers to plan.


Lewin, Kurt (1935). A Dynamic Theory of Personality: Selected Papers. McGraw-Hill Book Company, Inc.

Zeigarnik, Bluma (1938). "Das Behalten erledigter und unerledigter Handlungen" [On Finished and Unfinished Tasks] Psychologische Forschung.

Masicampo, E. J. and Baumeister, Roy F. (2011). Consider It Done! Plan Making Can Eliminate the Cognitive Effects of Unfulfilled Goals. Florida State University.

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