Can you study with your phone nearby? What the research says about multitasking

Many students study with a phone within reach. Many believe they can answer a message, glance at a video and still take in a chapter. The research on this is more interesting than the usual warnings suggest. Some findings are solid, some have not held up, and a few point to simple changes that do help.

What "multitasking" really is

What we call multitasking is mostly rapid switching between tasks. Psychologists have studied this for decades. In a well-known review, Stephen Monsell summarised the finding: responses are "substantially slower and, usually, more error-prone immediately after a task switch". This "switch cost" is reduced by a chance to prepare, but not eliminated. Experiments by Joshua Rubinstein, David Meyer and Jeffrey Evans found that the time lost in switching grew as the tasks became more complex.

So reading a chapter and replying to messages is not two tasks done at once. It is one task, interrupted again and again, with a small cost each time you switch back.

Are heavy multitaskers worse at focusing?

A famous 2009 study by Eyal Ophir, Clifford Nass and Anthony Wagner surveyed 262 university students about how many kinds of media they used at the same time. They then tested small groups of heavy and light media multitaskers. The heavy multitaskers were more affected by distracting information and were slower at switching between tasks.

The finding was widely reported, but later work made it less certain. In 2017 Wisnu Wiradhany and Mark Nieuwenstein ran two replications and a meta-analysis. They found only a weak association, which became non-significant once they corrected for the tendency of small studies to report larger effects. A 2018 review by Melina Uncapher and Wagner himself concluded that heavy media multitaskers tend to perform worse in a number of areas, but that many studies find no difference. It also left open the direction of cause: multitasking may change attention, or people who are already easily distracted may simply multitask more.

The honest summary is that there may be a link between heavy multitasking and weaker focus, but it has not been proven that multitasking damages the ability to concentrate.

Devices in class

Studies of real and simulated classes give clearer results. In a 2013 experiment in a simulated lecture, Faria Sana, Tina Weston and Nicholas Cepeda found that students who multitasked on a laptop scored lower on a test, and so did students who could see a classmate's multitasking laptop screen. The distraction spread to people nearby.

In 2019 Arnold Glass and Mengxue Kang tested this in an actual course of 118 students at a US university. Devices were allowed in some lectures and not in others. Quiz scores in class did not differ, but on the later unit exams and final exam, students did worse on material from the lectures in which devices were allowed, about a 5 per cent drop, or roughly half a letter grade. The drop appeared whether or not students said they had used a device themselves.

A study by Susan Ravizza and colleagues logged students' internet use on laptops in class. Non-academic browsing was common and was linked to lower class performance, even after the researchers accounted for motivation, interest and intelligence. Class-related internet use brought no benefit. This study shows a link, not proof of cause, but it points the same way.

Does a phone on the desk drain the brain?

In 2017 Adrian Ward and colleagues published "Brain Drain". In their first experiment, with 520 undergraduates, students whose silenced phones were in another room scored better on working-memory and reasoning tests than those whose phones lay on the desk. A second experiment found that turning the phone off made no difference; what seemed to matter was where it was. The effects were small.

This idea has been tested again, with mixed results. A pre-registered replication by Ana Ruiz Pardo and John Paul Minda found no difference between phone locations. Another study, by Hartmann and colleagues, found no overall effect of a phone on the desk on memory. A 2023 meta-analysis by Douglas Parry, pooling 56 effect sizes from earlier experiments, found a significant pooled effect only on working-memory capacity, and described the support as "limited" for an effect that is smaller than first thought.

So the evidence that a silent phone on the desk harms thinking is weaker than the headlines suggested. But nothing in this research suggests that having it there helps, and moving it to another room is an easy thing to try, although heavy phone users may feel anxious without it.

Notifications

Notifications may be a more direct problem, although the evidence is thinner and not all of it agrees. In a 2015 experiment, Cary Stothart, Ainsley Mitchum and Courtney Yehnert gave students a task that required sustained attention, while some of them received calls or texts on their own phones. The notifications "significantly disrupted performance", even when the students did not directly interact with their phones. The size of the effect was similar to that reported in earlier studies of people actively using a phone. A later study that played a generic smartphone sound, not each person's own alerts, found a difference of only about 3 milliseconds in response time and no difference in errors, so the evidence is not settled.

What seems to help

A few practical steps follow from this research, though the studies behind them mostly did not measure students' marks.

• Batch your notifications. In a two-week field experiment by Nicholas Fitz, Kostadin Kushlev and colleagues, people (mostly working adults, not students) who received notifications in batches three times a day felt more attentive, more productive and more in control of their phones. Those who turned notifications off entirely reported more anxiety, so switching everything off is not necessarily best.
• Put the phone out of reach while you study. Whatever the "brain drain" debate concludes, a phone in another room cannot interrupt you, and it removes the temptation to check it.
• Close other tabs and apps. The classroom studies link off-task device use with lower scores, and suggest that it can affect people nearby as well.
• Take short, planned breaks. A study by Atsunori Ariga and Alejandro Lleras found that attention in a long, dull task held up better when people briefly switched to a different mental task now and then. The breaks in that study were short recall tasks, not phone checks, so it does not show that breaks from studying raise marks, or which kind of break works best.

Some evidence also comes from schools. Louis-Philippe Beland and Richard Murphy studied English schools that banned phones and found that exam scores at age 16 rose slightly afterwards, with the gains concentrated among the lowest-achieving students. The schools chose their own policies, so it is not a controlled trial, and it may not carry over directly to other countries, but it suggests that the students most easily distracted may have the most to gain.

The bottom line

You usually cannot do two demanding things at once; you switch, and each switch has a cost. Using a device for other things during a class seems to lower later exam performance, for you and for those around you. One experiment found that notifications disrupted concentration even when people did not respond to them, although a later study using a generic alert sound found almost no effect. The claim that a phone simply sitting on the desk lowers your thinking power is less certain. The simplest plan is also a sensible one, though no study has tested it on students' marks: keep the phone out of sight and out of reach, check it at set times, and give the chapter your whole attention while you are on it.