What Is the Zeigarnik Effect? Close the Mental Tabs at Work

Why do you go home thinking about the single report you did not finish, the email you did not answer or the decision you postponed, even after completing dozens of tasks during the day?

Modern psychology explains this experience through the Zeigarnik Effect. The Zeigarnik Effect describes the tendency for unfinished tasks to remain more active in the mind than completed ones and to continue occupying a person’s attention.

Unfinished work is not merely remembered. It may consume mental energy, make it harder to direct attention to new tasks and increase the fatigue experienced at the end of the day. Constantly shifting priorities, consecutive meetings, messages, emails and notifications can create an increasing number of “open tabs” in the mind.

The main problem in modern working life is therefore not always the number of tasks waiting to be completed. The deeper problem may be the need to keep too many tasks mentally open at the same time.

What Is the Zeigarnik Effect?

The Zeigarnik Effect is a psychological concept describing people’s tendency to remember unfinished or interrupted tasks more easily than completed ones.

The concept is named after psychologist Bluma Zeigarnik, who studied the phenomenon during the 1920s. Her initial observation concerned restaurant staff who could remember the details of unpaid orders remarkably well but quickly forgot them once the bill had been settled.

The observation was later examined through experimental research. The findings suggested that unfinished tasks could remain mentally active because the brain continued to treat them as unresolved processes.

A completed task can be mentally closed. An unfinished one may continue consuming attention and memory resources, even when the person is not consciously thinking about it.

Why Do Unfinished Tasks Occupy the Mind?

The brain may treat unfinished tasks as open processes that still require a resolution. When a task begins, the person creates goals, possible actions, risks and decisions related to it. If the task remains incomplete, this mental structure may not fully close.

The person may therefore continue thinking about the task even after physically leaving work.

Unfinished tasks may create mental strain through:

• Continuing to think about work outside working hours

• Returning mentally to the same subject repeatedly

• Remembering the previous task while beginning a new one

• Planning unfinished work during rest periods

• Carrying the uncertainty created by incomplete tasks

• Remaining alert because of the fear of forgetting something

• Feeling as though nothing was truly completed during the day

This does not always mean that the person manages time poorly. The underlying problem may be a working system that keeps too many tasks open simultaneously.

What Is Attention Residue?

Attention residue occurs when part of a person’s attention remains attached to a previous task after they switch to another one without completing it.

Researcher Sophie Leroy used this concept to explain why task switching can be more cognitively costly than it appears.

Imagine that you are writing a report and stop to respond to a message. Although you have physically moved to the message, your mind may still carry the report’s final sentence, unresolved problem or pending decision.

If you then move from the message to a meeting, mental traces from both the report and the message may follow you into the new task.

The person may not be performing three tasks simultaneously, but the mind may be carrying residue from all three.

How Does Attention Residue Affect Performance?

Attention residue may reduce the mental resources available for the new task. A person may appear to be working while being unable to devote their full attention to the current activity.

This may affect:

• The ability to maintain focus

• Problem-solving capacity

• Decision quality

• Creativity

• Learning and remembering information

• The ability to notice mistakes

• Deep thinking about complex subjects

• Mental resilience

Frequent task switching can create a sense of movement in the short term. Movement, however, does not always mean progress.

Many employees touch numerous subjects throughout the day without feeling that they have explored any of them deeply enough. The end-of-day feeling of “I worked all day but completed nothing” may be associated with attention residue.

What Is the Difference Between Workload and Cognitive Load?

Workload concerns the amount of work a person needs to complete. Cognitive load refers to the mental capacity used to understand, remember, prioritise and manage that work.

Two employees may have a similar number of tasks but experience very different levels of cognitive load.

Work may feel more manageable when tasks are clearly defined, priorities are visible and employees can progress without constant interruption.

By contrast, shifting priorities, unclear expectations and frequent interruptions can make even a smaller number of tasks feel mentally exhausting.

Factors that increase cognitive load include:

• Conflicting priorities

• Unclear task descriptions

• Constant notifications

• Consecutive meetings

• Projects without completion criteria

• Managers who frequently change direction

• Working on several projects simultaneously

• Messages and emails waiting for responses

• Repeatedly postponed decisions

• The expectation of being constantly available

Organisations should therefore evaluate not only the amount of work, but also how that work is mentally organised.

Why Is Task Switching Mentally Exhausting?

When the mind moves from one task to another, it does not simply begin a new activity. It also attempts to leave the previous context and construct a new one.

Each task contains a different set of information, goals, relationships and decisions. Switching tasks requires the mind to adjust to new rules.

When task switching happens frequently, a person may:

• Try to remember where they stopped

• Reload the goals of the new task

• Move between different working rules

• Keep unfinished tasks active in memory

• Spend energy repeatedly rebuilding focus

These transitions may appear brief individually, but their cumulative cost can become significant across the day.

The problem is not always doing several things at once. It is often leaving many tasks unfinished and returning to them repeatedly.

How Does Digital Work Increase Open Mental Tabs?

Digital tools make information and communication more accessible, but they can also create continuous interruptions.

Email, instant messaging, project management platforms, online meetings and mobile notifications may push employees to move between many subjects throughout the day.

Open mental tabs in digital work may include:

• Unanswered emails

• Unread messages

• Incomplete reports

• Pending approvals

• Postponed decisions

• Presentations waiting to be prepared

• Meeting notes requiring follow-up

• Multiple active projects

• Tasks without a clear deadline

• Constantly expanding to-do lists

When many tabs are open on a computer, the system’s available memory decreases. In a similar way, the human mind may struggle when carrying too many unresolved processes at once.

This analogy does not suggest that the human mind works exactly like a computer. It simply offers a useful way to understand how open tasks consume limited attention.

What Is a Culture of Completion?

A culture of completion is a working approach in which organisations value not only starting new tasks, but also bringing existing work to a meaningful conclusion.

In many organisations, productivity may be measured through the length of to-do lists, the number of meetings or the number of parallel projects. Yet starting many activities does not necessarily indicate that value is being produced.

A culture of completion prioritises:

• Limiting the number of priorities

• Making critical work visible

• Defining task completion criteria

• Giving employees uninterrupted working time

• Making completed work visible

• Closing existing tasks instead of constantly adding new ones

• Evaluating quality and outcomes as well as speed

• Reducing unclear responsibilities

Every completed task is more than an item removed from a list. It is also a mental process that can finally be closed.

Why Is a To-Do List Not Enough?

To-do lists are valuable because they make tasks visible. However, constantly adding items without completing them may increase mental strain.

A long list may create a sense of falling behind instead of providing control.

An effective task system should answer not only “What should I do?” but also:

• Why is this task important?

• When will it begin?

• What is the next concrete action?

• Who owns the task?

• When will it be considered complete?

• Which information or decision is required?

• Is the task still necessary?

• Which tasks will not be completed today?

Productivity is not only about adding tasks. It is also about removing unnecessary work and completing what matters.

How Can You Clear Your Mental RAM?

It is impossible to eliminate unfinished work completely. Working life will always contain ongoing projects, pending decisions and future tasks.

The goal is not to finish everything on the same day. The goal is to create a reliable system so that the mind does not need to carry every task continuously.

Transfer Tasks to a Reliable System

One of the central ideas in David Allen’s Getting Things Done approach is that the mind should be used for thinking, not for storing tasks.

Keeping every responsibility in memory may cause a person to remain constantly alert because of the fear of forgetting something.

Tasks can be transferred to:

• A physical planner

• A digital task manager

• Project management software

• A calendar

• A daily planning page

• A team task board

• A note-taking application

The reliability of the system matters more than the specific tool. When a person trusts that they can return to a recorded task, the mind may feel less need to repeat it constantly.

The task should include the next concrete action, not only a general title.

“Create the first draft of the first three slides” provides a clearer starting point than “Prepare the presentation.”

Define What Done Means

Many tasks remain open not because they cannot be completed, but because nobody knows what completion actually looks like.

When is a report finished?

• When the first draft is written?

• When it is sent to the manager?

• When revisions are completed?

• When final approval is received?

Without a shared answer, employees may repeatedly return to the same task.

A Definition of Done explains the criteria required to close a task.

It may include:

• The expected output

• Quality criteria

• The deadline

• The person responsible for approval

• The required file format

• The communication channel

• The points that must be checked

• The next stage to which the work will be transferred

Clear completion criteria can prevent employees from working in prolonged uncertainty.

Protect Time for Deep Work

Deep work is a period in which distractions are restricted and the person focuses uninterruptedly on one valuable task.

Popularised by Cal Newport, this approach is especially useful for analysis, strategy, writing, design, research and problem solving.

To support deep work:

• Focus blocks can be added to the calendar.

• Notifications can be temporarily disabled.

• Email checking can be limited to certain times.

• Meeting-free periods can be protected.

• Team members can be informed about unavailable hours.

• One primary objective can be selected for each work block.

• Necessary information and documents can be prepared beforehand.

Deep work does not require uninterrupted focus throughout the entire day. Even short but protected blocks may support mental performance.

Review Open Tasks Regularly

Transferring tasks to a system is not enough. If the system is not reviewed regularly, it loses credibility.

During a weekly review, the following questions may be asked:

• Which tasks were completed?

• Which tasks are still important?

• Which tasks are no longer necessary?

• Which responsibilities can be delegated?

• Which task is waiting for a decision?

• Which project lacks a clear next step?

• Which task would create the greatest mental relief if completed?

• Which open tab is being carried only out of habit?

Regular review prevents the task system from becoming a passive storage area.

How Can Leaders Protect Employees’ Attention?

Leaders influence not only employees’ schedules and workloads, but also their attention.

Constantly changing instructions, unclear priorities and repeated interruptions may consume a team’s mental energy. Clear goals and protected working time can make focus easier.

Limit Priorities

When every task is declared urgent, no task is genuinely prioritised.

Leaders should clarify:

• What is the most important goal right now?

• Which task can wait?

• Which work can be stopped?

• When a new task arrives, which current task will be postponed?

• Which result will define success?

Prioritisation involves not only choosing what to do, but also consciously postponing or ending other work.

Review Meeting Culture

Meetings may be necessary for decisions, collaboration and information sharing. However, purposeless or consecutive meetings can make deep work difficult.

A healthier meeting culture may include:

• A clear objective for every meeting

• An agenda shared in advance

• Only necessary participants

• Written updates for purely informational subjects

• Transition time between meetings

• Clear decisions and owners at the end

• Protected meeting-free work blocks

A meeting occupies more than calendar time. It also requires the employee to leave a previous task and later rebuild focus.

Evaluate Existing Work Before Adding New Tasks

Leaders may sometimes add responsibilities without reducing previous ones. This can cause employees to carry a growing number of open mental tabs.

Whenever a new task is introduced, leaders should ask:

“What existing task are we reducing, postponing or stopping to make room for this?”

This question makes both workload and cognitive load more visible.

Make Completed Work Visible

Organisational cultures often discuss new targets and remaining problems while completed work is quickly forgotten.

This can cause employees to feel that they are never catching up.

Making completed work visible may:

• Strengthen the sense of progress

• Support motivation

• Clarify success criteria

• Help mentally close open tasks

• Ensure employee contributions are recognised

A culture of completion is not only about producing outcomes. It is also about noticing them.

What Is the To-Do, Done and To-Think Approach?

Future working cultures may require more than to-do lists. Employees need to plan tasks, complete them and protect time for thinking.

A three-layer approach can be used:

To-Do

This layer includes tasks, responsibilities and projects that need to be completed.

It involves:

• Recording tasks

• Setting priorities

• Assigning owners

• Planning time

• Clarifying next actions

Done

This layer concerns bringing work to completion according to defined quality and time criteria.

It involves:

• Checking completion criteria

• Receiving necessary approvals

• Sharing the outcome

• Closing the task in the system

• Recording lessons learned

To-Think

This layer refers to consciously protected time for thinking, learning, reviewing and creating new ideas.

During this time, leaders and employees may:

• Analyse complex problems

• Evaluate strategic decisions

• Consider future risks

• Learn from experience

• Develop new ideas

• Review working practices

Being constantly busy is not the same as producing value. Some work requires rapid responses, while other work requires uninterrupted thought.

Is the Zeigarnik Effect Always Negative?

The Zeigarnik Effect should not always be considered negative. Keeping an unfinished task mentally active may encourage a person to return and complete it.

Starting a small part of a task can also help break procrastination. Once the first step has been taken, the mind’s tendency to keep the process active may encourage continuation.

The effect may become exhausting when too many unfinished tasks accumulate.

The distinction is important:

• A limited number of open tasks may support motivation.

• Many vague and uncontrolled tasks may create mental strain.

• A task with a clear plan may feel more manageable.

• A task without a next step may occupy more mental space.

• A consciously paused task is different from one repeatedly interrupted.

The goal is not to complete everything immediately. It is to manage open tasks intentionally.

Let’s Reflect Together

You can ask yourself the following questions to identify the open tabs in your mind:

• How many unfinished tasks am I mentally carrying?

• Which of them are genuinely important?

• Which tasks remain only because of habit?

• Which task lacks a clear next action?

• Which single task would create the greatest mental space if completed today?

• Can I close the current task before moving to the next one?

• Is there protected time for uninterrupted thinking in my working day?

• As a leader, am I giving my team more work or more opportunities to finish?

• Does our organisation reward constant busyness or meaningful value creation?

• Which open tab do I need to close completely?

The purpose of these questions is not to add more tasks. It is to make the sources of mental strain visible.

Conclusion: Creating Mental Space Creates Space for the Future

Modern working life continuously encourages employees to do more. More meetings, more projects, more messages and more targets may appear to be natural indicators of high performance.

However, human attention, decision-making and learning capacity are not unlimited.

The Zeigarnik Effect explains why unfinished tasks remain active in the mind. Attention residue shows how traces of previous tasks follow us when we switch activities. Deep work reminds us that valuable results require uninterrupted attention.

The shared message is clear: when the mind is continuously interrupted, it does not only become tired. Its capacity to learn, create, decide and solve problems may also weaken.

Successful leaders of the future will not simply assign more tasks. They will protect their teams’ attention, mental energy and capacity to think.

The secret of productivity is not always doing more. It is completing the right work at the right time with full attention.

Open tabs slow down a computer. Open tasks can exhaust the mind. A culture of completion may help people create space not only in their calendars, but also in their minds.

Listen to the Improve Your Working Life Podcast

To explore this subject in greater depth, listen to our podcast episode “Close the Open Tabs in Your Mind: How the Zeigarnik Effect Sabotages Performance at Work.” The episode discusses the impact of unfinished tasks on mental energy, attention residue, deep work, a culture of completion and how leaders can protect their teams’ attention from a broader perspective.

Organisations that want to strengthen employee experience not only through work processes but also through holistic practices supporting physical and psychological well-being can explore Happ Health’s Corporate Health Solutions.

References

• Allen, D. (2015). Getting Things Done: The Art of Stress-Free Productivity. Penguin Books.
• Baumeister, R. F., & Tierney, J. (2011). Willpower: Rediscovering the Greatest Human Strength. Penguin Press.
• Kahneman, D. (2011). Thinking, Fast and Slow. Farrar, Straus and Giroux.
• Leroy, S. (2009). Why Is It So Hard to Do My Work? The Challenge of Attention Residue When Switching Between Work Tasks. Organizational Behavior and Human Decision Processes, 109(2), 168–181.
• Newport, C. (2016). Deep Work: Rules for Focused Success in a Distracted World. Grand Central Publishing.
• World Economic Forum. (2025). The Future of Jobs Report 2025.
• Zeigarnik, B. (1927). Das Behalten Erledigter und Unerledigter Handlungen. Psychologische Forschung, 9, 1–85.