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Focus basics

Why Can't I Focus? Common Causes of Distraction

By LaserMind Team ·

A woman looking at her phone at a desk with a coffee cup
Photo: George Milton on Pexels

What "I can't focus" usually means

Focus is the everyday word for selective and sustained attention working together: choosing one task and staying with it while you ignore what competes for it. What is attention? explains the different kinds.

When focus fails, it tends to fail in one of three ways:

  • Something pulls you away: a notification, a colleague, a noise.
  • Your mind drifts to thoughts that have nothing to do with the task, although nothing around you has changed.
  • Your attention goes slack: you read the same paragraph three times, or miss things you would normally catch.

The causes below map onto these. Most of the research comes from laboratory tasks and short studies, so it can tell you what tends to matter for people in general, not which cause applies to you on a particular day.

Sleep loss

Lack of sleep hits attention hard. A meta-analysis of 70 articles looked at the effect of up to 48 hours without sleep on six kinds of cognitive task [1]. The effects ranged from large, for lapses in simple attention tasks (g = −0.776), to small and not statistically significant, for accuracy in reasoning [1].

A whole night without sleep is not the only concern. A 2017 meta-analysis of 61 studies in which people were allowed less sleep than usual, rather than none, found a negative effect on cognition overall, and on sustained attention in particular (g = −0.409) [6].

Short nights also add up without your noticing. In a laboratory study of 48 healthy adults aged 21 to 38, spending 6 hours or less in bed each night for two weeks produced deficits in cognitive performance equivalent to up to two nights without any sleep [7]. The participants' ratings of their own sleepiness rose only a little after the first days, which the authors read as a sign that they were largely unaware of how far their performance had dropped [7].

So if your focus is poor, your last few nights are the first thing to look at. Sleep and memory covers what sleep does for learning.

Phones and notifications

In a lab experiment, receiving phone notifications during an attention-demanding task disrupted performance even though the participants did not touch their phones [2]. The authors describe the disruption as comparable in size to the effects seen when people actively use a phone for calls or texts, and suggest that even a short alert can set off thoughts unrelated to the task [2].

Outside the lab, 221 people from the general population spent one week with their notification alerts on and their phones within reach, and another week with alerts off and their phones put away [8]. They reported more inattention and hyperactivity in the week with alerts on, and higher inattention went with lower self-rated productivity and well-being [8]. These were self-ratings, not performance tests.

Not every study finds a cost in performance. In a pre-registered experiment with students, a visible phone made people feel more alert to it and more distracted, and incoming notifications strengthened that feeling, yet none of this was related to how well they did on a stop-signal task, which measures holding back a response [9].

The evidence that notifications cost you something is reasonable but not uniform. How to focus better covers what to do about them.

The phone lying on the desk

A popular claim says that your own phone, lying silently nearby, drains your thinking. It comes from a 2017 paper whose two experiments suggested that the mere presence of people's own smartphones reduced their "available cognitive capacity", most of all in those most dependent on their phones [10].

Later work has not borne this out well:

  • A direct replication failed. A pre-registered replication of the second experiment used the same tasks (a working-memory task and a go/no-go task) and the same phone locations (on the desk, in a pocket or bag, or outside the room). It found no difference between the locations on either task [3].
  • One meta-analysis found no effect. Pooling 33 studies with 4,368 participants, it found no significant effect of a phone's mere presence on cognitive outcomes (d = −0.02), and the result did not depend on how dependent people were on their phones [4].
  • Another found a small effect on one ability. Across six meta-analyses covering 7,093 participants, the only significant pooled effect was a negative effect on working-memory capacity, smaller than the original idea predicted; results for the other abilities were null, and the studies varied widely in method and generally had low statistical power [11].

Taken together, the case against a silent phone's mere presence is stronger than the case for it. Notifications have more support, although it rests on a lab experiment and a field study of self-ratings.

A wandering mind

Using a phone app that contacted people at random moments during their waking hours, researchers collected reports from 2,250 adults on what they were doing and what they were thinking about [5]. Their minds were wandering in 46.9% of the samples, and in at least 30% of the samples taken during every activity but one [5]. People were also less happy when their minds were wandering than when they were not [5].

Drifting matters for performance too. A meta-analysis of 88 correlations from non-clinical adult samples found that more mind-wandering generally went with worse task performance, and that the link was stronger for more complex tasks [12]. People with fewer cognitive resources tended to mind-wander more [12]. These are correlations: they show that drifting and weaker performance go together, not which causes which.

In itself, then, a wandering mind is not a sign that something is wrong. What you can practise is noticing that you have drifted and coming back. LaserMind's Breath Counter asks you to do exactly that. Breath counting has been validated as a measure of mindfulness: in four studies with more than 400 participants in total, people who were better at counting their breaths also showed less mind-wandering [13].

Try it on LaserMind

▶ Breath Counter & Pacer

Count your out-breaths from 1 to 10, and press "I lost count" each time you notice your mind has wandered.

Stress

A meta-analysis of 51 studies with 2,486 participants looked at what short bouts of stress, created in the laboratory with tasks such as giving a speech to a panel of evaluators or holding a hand in ice-cold water, do to executive functions [14]. Stress impaired working memory (g = −0.197) and cognitive flexibility (g = −0.300), and it impaired interference control, the ability to ignore distracting information (g = −0.208) [14]. It slightly improved response inhibition, holding back an action (g = +0.296) [14].

The effects were small, the flexibility estimate rested on only six studies, and most participants were young adults from Western samples [14]. These were brief, acute stressors: the studies do not show what weeks of ongoing pressure do to concentration.

Boredom, and tasks that are too easy or too hard

Boredom and attention are closely tied. In experiments, people who tend to get bored easily performed worse on a sustained-attention task, over and above questionnaire measures of depression and of attention problems [15]. Exploratory results also fitted the idea that attention failures can cause boredom, and that sustained-attention tasks may themselves be boring [15].

How hard the task is matters in both directions. When people studied English–Spanish word pairs that were easy, matched to their level, or difficult, they mind-wandered least on the matched material; stronger learners drifted more on easy pairs and weaker learners on difficult ones [16]. Words studied while the mind was wandering were remembered less well [16]. In a reading study, people mind-wandered more on difficult texts than on easy ones, and mind-wandering hurt comprehension more for the difficult texts [17].

So drifting off can be a sign that the task is pitched wrong for you right now, not only that you are tired.

Noise and your surroundings

A Bayesian meta-analysis of 65 studies found that background noise, speech and music all had a small but reliable negative effect on reading performance [18]. Speech you can understand and music with lyrics were the most distracting, and the disruption was generally similar for adults and children [18].

These studies measured reading in experiments, so they cannot tell you how much a particular café or open-plan office affects your working day.

Several causes at once

On a bad day, several of these may be at work at once: a short night, say, followed by a dull task in a noisy room. The evidence is not equally strong for each. Sleep loss and mind-wandering rest on meta-analyses and a large study of daily life; notifications on single studies with mixed results; boredom and task difficulty on small lab studies; and the silent phone on the desk has the weakest case of all.

Finding your own pattern

This page is about causes. For what to do about them, step by step, see How to focus better.

A useful first step is to notice when your focus slips and what was going on at the time. The Deep Work Timer lets you name one task, work on it for 25, 50 or 90 minutes and tap "I got distracted" each time you notice your attention has wandered. At the end it shows your focused minutes and the distractions you noticed per hour. The count is your own tally, not a test: compare it only with your own earlier sessions, and keep a note of what was happening on your worst and best days.

Try it on LaserMind

▶ Deep Work Timer

Name one real task, set a block and tally each time you drift. Jot down what pulled you away.

When to talk to a doctor

Everyone has days when they cannot concentrate. Talk to a doctor or another qualified professional if:

  • difficulty concentrating has lasted for weeks, even though you are sleeping reasonably and your surroundings are workable;
  • it is affecting your studies, work, relationships or safety, for example when driving;
  • it is new, getting worse, or began after a head injury, an illness or a change of medicine;
  • it comes with other changes, such as persistent low mood or worry, severe daytime sleepiness, memory problems or feeling unwell.

If trouble concentrating comes on suddenly together with confusion, a severe headache or other new symptoms, get urgent medical help.

Concentration problems can have many causes, including physical and mental health conditions and the effects of medicines, and only a proper assessment can sort them out. LaserMind's exercises and tools are practice, not diagnostic tests.

What the research says

◆ SupportedSleep loss impairs attention: most of all simple attention after up to 48 hours awake [1], and sustained attention after repeated short nights [6][7]. Mind-wandering is common in daily life [5] and goes with weaker task performance [12].
◇ ConditionalNotifications disrupted attention in one lab experiment and raised self-rated inattention in a week-long field study, but did not affect a stop-signal task in another experiment [2][8][9]. Brief lab stress had small effects on working memory, flexibility and interference control [14]. Background speech, music and noise had small effects on reading [18]. Material that is too easy or too hard was linked with more mind-wandering in small studies [16][17].
✕ Not establishedThat a silent phone lying nearby harms focus [3][4][11]. That any exercise, app or timer, including LaserMind's, can tell you why your concentration is poor.

What research has not established

  • Most of the evidence comes from short laboratory experiments, often with students or young adults. The sleep meta-analysis covered total sleep loss of up to 48 hours, which is more extreme than most people's short nights [1].
  • The notification evidence rests on single studies with mixed results, and the field study used self-ratings rather than performance tests [8].
  • The phone-presence studies varied widely in method and generally had low statistical power [11].
  • The link between mind-wandering and performance comes from correlations [12]. The stress studies used brief laboratory stressors with mostly young Western participants [14].
  • Studies usually look at one cause at a time, while in daily life they overlap. None of them can tell you which cause applies to you.
  • This article is general science education, not medical advice. Your Deep Work Timer tally is a personal record, not a validated measure of attention, and LaserMind's Breath Counter has not itself been tested as a measure.

Frequently asked questions

Is it normal for my mind to wander this much? Yes. In the large experience-sampling study, people's minds were wandering in 46.9% of the moments sampled [5]. What is worth noticing is whether drifting is getting in the way of things you need to do, and when it happens most.

Should I keep my phone in another room? The evidence that a silent phone harms your thinking is weak [4][11], while notifications have somewhat more evidence against them [2]. Moving the phone away still makes sense if you know you will be tempted to check it.

Can LaserMind tell me why I can't focus? No. Our exercises and tools are practice, not tests for any condition. If you are worried about your concentration, speak to a doctor or another qualified professional.

What the research says

Last evidence check 2026-10-17
ⓘ Background

Switching between tasks costs time and accuracy, even when you can prepare for the switch. Trained task [19]

ⓘ Background

In a lab experiment, simply receiving phone notifications, without answering them, disrupted performance on an attention-demanding task, an effect the authors describe as comparable to that of actively using a phone. Trained task [2]

Limited evidence

In one-day studies with university students, Pomodoro-style fixed breaks gave mixed results: one found less fatigue and distraction than self-chosen breaks with similar task completion, another found no difference in productivity, task completion or flow. Daily life [20][21]

Not supported

The popular idea that a phone merely lying nearby drains your thinking is weakly supported: one meta-analysis found no overall effect, and another found only a small effect on working memory. Daily life [4][11]

ⓘ Background

Breath counting has been validated as a way to measure mindfulness; studies of it as a training method are still few. Trained task [13]

References

  1. Lim, J., & Dinges, D. F. (2010). A meta-analysis of the impact of short-term sleep deprivation on cognitive variables. Psychological Bulletin, 136(3), 375–389. https://doi.org/10.1037/a0018883
  2. Stothart, C., Mitchum, A., & Yehnert, C. (2015). The attentional cost of receiving a cell phone notification. Journal of Experimental Psychology: Human Perception and Performance, 41(4), 893–897. https://doi.org/10.1037/xhp0000100
  3. Ruiz Pardo, A. C., & Minda, J. P. (2022). Reexamining the “brain drain” effect: A replication of Ward et al. (2017). Acta Psychologica, 230, 103717. https://doi.org/10.1016/j.actpsy.2022.103717
  4. Hartanto, A., Lua, V. Y. Q., Kasturiratna, K. T. A. S., et al. (2024). The effect of mere presence of smartphone on cognitive functions: A four-level meta-analysis. Technology, Mind, and Behavior, 5(1), 1–14. https://doi.org/10.1037/tmb0000123
  5. Killingsworth, M. A., & Gilbert, D. T. (2010). A Wandering Mind Is an Unhappy Mind. Science, 330(6006), 932–932. https://doi.org/10.1126/science.1192439
  6. Lowe, C. J., Safati, A., & Hall, P. A. (2017). The neurocognitive consequences of sleep restriction: A meta-analytic review. Neuroscience & Biobehavioral Reviews, 80, 586–604. https://doi.org/10.1016/j.neubiorev.2017.07.010
  7. Van Dongen, H. P. A., Maislin, G., Mullington, J. M., & Dinges, D. F. (2003). The Cumulative Cost of Additional Wakefulness: Dose-Response Effects on Neurobehavioral Functions and Sleep Physiology From Chronic Sleep Restriction and Total Sleep Deprivation. Sleep, 26(2), 117–126. https://doi.org/10.1093/sleep/26.2.117
  8. Kushlev, K., Proulx, J., & Dunn, E. W. (2016). "Silence Your Phones": Smartphone Notifications Increase Inattention and Hyperactivity Symptoms. Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems, 1011–1020. https://doi.org/10.1145/2858036.2858359
  9. Johannes, N., Veling, H., Verwijmeren, T., & Buijzen, M. (2019). Hard to Resist?: The Effect of Smartphone Visibility and Notifications on Response Inhibition. Journal of Media Psychology, 31(4), 214–225. https://doi.org/10.1027/1864-1105/a000248
  10. Ward, A. F., Duke, K., Gneezy, A., & Bos, M. W. (2017). Brain Drain: The Mere Presence of One’s Own Smartphone Reduces Available Cognitive Capacity. Journal of the Association for Consumer Research, 2(2), 140–154. https://doi.org/10.1086/691462
  11. Parry, D. A. (2024). Does the mere presence of a smartphone impact cognitive performance? A meta-analysis of the "brain drain effect". Media Psychology, 27(5), 737–762. https://doi.org/10.1080/15213269.2023.2286647
  12. Randall, J. G., Oswald, F. L., & Beier, M. E. (2014). Mind-wandering, cognition, and performance: A theory-driven meta-analysis of attention regulation. Psychological Bulletin, 140(6), 1411–1431. https://doi.org/10.1037/a0037428
  13. Levinson, D. B., Stoll, E. L., Kindy, S. D., Merry, H. L., & Davidson, R. J. (2014). A mind you can count on: Validating breath counting as a behavioral measure of mindfulness. Frontiers in Psychology, 5, 1202. https://doi.org/10.3389/fpsyg.2014.01202
  14. Shields, G. S., Sazma, M. A., & Yonelinas, A. P. (2016). The effects of acute stress on core executive functions: A meta-analysis and comparison with cortisol. Neuroscience & Biobehavioral Reviews, 68, 651–668. https://doi.org/10.1016/j.neubiorev.2016.06.038
  15. Hunter, A., & Eastwood, J. D. (2018). Does state boredom cause failures of attention? Examining the relations between trait boredom, state boredom, and sustained attention. Experimental Brain Research, 236(9), 2483–2492. https://doi.org/10.1007/s00221-016-4749-7
  16. Xu, J., & Metcalfe, J. (2016). Studying in the region of proximal learning reduces mind wandering. Memory & Cognition, 44(5), 681–695. https://doi.org/10.3758/s13421-016-0589-8
  17. Feng, S., D’Mello, S., & Graesser, A. C. (2013). Mind wandering while reading easy and difficult texts. Psychonomic Bulletin & Review, 20(3), 586–592. https://doi.org/10.3758/s13423-012-0367-y
  18. Vasilev, M. R., Kirkby, J. A., & Angele, B. (2018). Auditory Distraction During Reading: A Bayesian Meta-Analysis of a Continuing Controversy. Perspectives on Psychological Science, 13(5), 567–597. https://doi.org/10.1177/1745691617747398
  19. Monsell, S. (2003). Task switching. Trends in Cognitive Sciences, 7(3), 134–140. https://doi.org/10.1016/S1364-6613(03)00028-7
  20. Biwer, F., Wiradhany, W., oude Egbrink, M. G. A., & de Bruin, A. B. H. (2023). Understanding effort regulation: Comparing 'Pomodoro' breaks and self-regulated breaks. British Journal of Educational Psychology, 93(S2), 353–367. https://doi.org/10.1111/bjep.12593
  21. Smits, E. J. C., Wenzel, N., & de Bruin, A. (2025). Investigating the effectiveness of self-regulated, Pomodoro, and Flowtime break-taking techniques among students. Behavioral Sciences, 15(7), 861. https://doi.org/10.3390/bs15070861