A phone can interrupt reading without being touched
A phone sitting within reach can become part of a reading task even when its owner never picks it up.
Incoming messages can invite a quick glance, create an expectation of social contact or simply make it harder to remain absorbed in the page. A new experiment published in Scientific Reports on 9 November 2026 investigated these possibilities by comparing reading with no visible phone, with a visible silent phone and with a visible phone receiving WhatsApp notifications.
The researchers combined conventional comprehension questions and self-reports with measures of brain activity, heart activity and eye movements.
Their results suggest that active notifications, rather than the mere sight of a silent handset, were associated with poorer comprehension and greater anxiety in this small laboratory sample.
The findings are relevant to study rooms and workplaces, but they do not establish that every notification produces the same effect in everyday life.
What the researchers wanted to separate
Much discussion of smartphones and concentration treats the device as one undifferentiated distraction.
In practice, several different processes may be involved. A person might notice a handset on the desk, anticipate a message, hear or see an alert, feel an urge to respond, or actually interrupt a task to use an application.
Those experiences are not interchangeable.
The Brazilian research team designed three experimental conditions to distinguish at least some of them.
In the No Phone condition, the handset was not visible.
In Phone Off, it was visible but silent.
In Phone On, it remained visible while WhatsApp notifications were active.
The comparison matters because it allows researchers to ask whether having a phone nearby is sufficient to change reading performance, or whether the additional salience of notifications plays a larger role.
It is still a laboratory simplification of everyday phone use, not a complete account of digital distraction.
Who took part in the experiment
The study involved 36 WhatsApp users with a reported mean age of 22.54 years.
This is a relatively young and small group, which limits how confidently the results can be applied to schoolchildren, older adults or workers with different patterns of device use.
Participants completed a reading experiment under the three phone conditions while the researchers gathered several kinds of information.
Self-report questionnaires captured subjective experiences, including anxiety and perceived understanding. A comprehension assessment provided a behavioural measure of what participants actually retained or understood.
Electroencephalography, commonly called EEG, recorded electrical activity at the scalp.
Electrocardiography, or ECG, monitored cardiac signals, while eye tracking recorded aspects of gaze behaviour.
These tools are complementary rather than interchangeable: a person’s reported stress, their test score and a change in a physiological signal answer different questions.
Why multiple measurements are useful
A study relying only on a questionnaire could identify perceived distraction without showing whether performance changed. A study relying only on a comprehension test could identify a difference in scores but reveal little about the accompanying experience.
Adding physiological measures offers another window into what participants may have been doing during reading. EEG can reveal changes in frequency-specific brain activity, although a frequency band cannot be interpreted as a direct readout of a single mental state.
Eye tracking can indicate how visual attention is distributed, but stable eye movement measures do not prove that the reader’s thoughts stayed focused on the text. ECG adds a physiological channel that may help researchers consider arousal or autonomic responses.
Using several measures therefore allows findings to converge or diverge, and both outcomes can be informative.
In this experiment, the different measures did not all move together.
Notifications and comprehension
The clearest behavioural pattern reported by the authors concerned the Phone On condition.
Participants exposed to active WhatsApp notifications reported higher anxiety and lower subjective understanding, and they performed worse on the objective reading-comprehension measure than under the No Phone and Phone Off conditions.
That contrast supports the idea that notifications can impose a cost even without an overt switch to messaging.
It does not mean that a phone that is merely visible always undermines comprehension.
Indeed, the distinction between the silent-phone and notification conditions is central to the result.
The published abstract does not establish a universal percentage reduction in comprehension, and no such percentage should be inferred from the finding.
The experiment provides evidence of a difference under its specific testing conditions rather than a forecast of lost grades or productivity across a full school or working day.
What the EEG signal showed
The authors reported a significant increase in frontal beta-band EEG power, in the frequency range from 13 to 30 hertz, during the active-notification condition relative to the two comparison conditions.
They interpret this pattern as consistent with greater recruitment of cognitive-control processes to resist attending to messages.
That is a plausible interpretation, but it should not be presented as direct proof that a particular thought or inhibition mechanism was occurring.
Beta activity can be affected by several cognitive and physiological factors, and scalp EEG does not identify a unique mental process simply from a band-power change.
The result is best understood alongside the comprehension and anxiety findings: notifications coincided with a change in a frontal electrical signal and worse reading outcomes.
It is not a clinical brain scan or evidence of neurological injury.
What did not change significantly
An important counterweight to the positive findings is that the researchers did not observe significant differences in global EEG power or the reported eye-movement metrics across the three conditions.
This is not an embarrassment to the study; it helps specify its boundaries. A local frontal beta-band effect can coexist with an absence of a broad global EEG effect.
Similarly, readers can experience internal distraction or impaired comprehension without a dramatic change in the aggregate eye movements measured by a particular setup. A non-significant result should not be converted into proof of exact equality, especially in a small sample.
The measures may have been insensitive to subtle effects, or there may genuinely have been little difference in the aspects of gaze they captured.
Either way, the reported pattern is more selective than a claim that notifications disrupted every physiological and behavioural indicator.
WhatsApp dependence and reported distress
The researchers also examined questionnaire measures related to WhatsApp dependence.
Higher dependence scores correlated positively with anxiety, perceived stress and general mental-health indicators reported in the study.
This finding concerns associations among measured characteristics; it does not establish that WhatsApp dependence caused a mental-health problem.
People who are more anxious might check messages more frequently, a third factor might influence both, or the relationship might operate in several directions.
The reading experiment and the dependence correlations therefore support different kinds of conclusions.
The experimental comparison speaks to short-term effects under controlled notification conditions.
The questionnaire correlations describe how reported tendencies and experiences varied across individuals.
Conflating the two would make the evidence appear stronger than it is.
How to understand the three conditions
The distinction among No Phone, Phone Off and Phone On offers a practical lesson about study design.
If the researchers had compared only a notification-heavy phone with no phone, any difference could have been attributed either to the device’s visibility or to the alerts.
The silent-phone condition provides a more informative intermediate comparison.
Nevertheless, the conditions do not isolate every possible aspect of a smartphone.
Participants may have differed in how important incoming messages felt, whether they expected a reply, or how accustomed they were to working with alerts.
The experimental setting itself may have influenced awareness of the phone.
The authors studied WhatsApp users rather than all smartphone owners, and the conclusions should not automatically be extended to every platform, notification type or task.
Reading prose for a comprehension test is also different from navigating, having a conversation or completing repetitive work.
Why the result matters beyond a laboratory
For students, the most immediate implication is that turning off notifications may be more consequential than merely moving a silent phone a short distance away.
For workplaces, it raises questions about how communication tools are configured during demanding tasks.
Constant message alerts may compete with activities that require sustained understanding, such as reading technical documentation, reviewing contracts or studying research.
However, the experiment did not test a classroom intervention, an employer policy or a long-term productivity programme.
It therefore cannot quantify the benefit of a notification-free study hour or determine the best notification policy for a whole organisation. A practical recommendation to reduce avoidable alerts during focused reading is consistent with the evidence, but should be framed as a low-cost precaution rather than a precisely measured intervention outcome.
Limitations that matter
The first limitation is sample size: 36 participants provide useful experimental evidence but relatively little room for precise subgroup comparisons.
The participants’ young average age and WhatsApp-user status also narrow generalisability.
Second, the experiment focused on a particular reading task and short-term exposure, not repeated real-world study sessions across weeks or months.
Third, subjective anxiety and understanding can be influenced by expectations, and physiological indicators require careful interpretation.
Fourth, not every measure showed a significant effect, so the findings do not support a blanket claim of universal attentional disruption.
Finally, a study of notification salience is not evidence that smartphones as a category are harmful.
The device can be a useful reading, accessibility and communication tool; the question investigated here is the additional cognitive demand created by active messaging alerts during a focused task.
What stronger evidence could look like
Larger experiments could recruit participants across age groups, occupations and levels of phone dependence.
Researchers might vary the frequency, urgency and sensory form of notifications, while keeping the reading material and testing conditions comparable.
It would also be valuable to distinguish a visible alert from a sound, vibration or expectation that an important message might arrive.
Longer field studies could assess whether changes observed in a controlled room translate into meaningful differences in sustained learning or work output.
Researchers should report effect sizes and uncertainty for comprehension, subjective experience and physiological measurements, rather than relying on whether a statistical threshold was crossed.
Replication would be especially helpful for understanding the frontal beta-band finding and determining whether it persists across equipment, tasks and participant populations.
What readers can reasonably take away
The study offers a focused finding: in a 36-person experiment, active WhatsApp notifications during reading were linked to worse comprehension, higher reported anxiety and greater frontal beta-band EEG power than conditions with no visible phone or a silent visible phone.
Global EEG power and eye-movement measures did not show significant differences.
This pattern is consistent with notifications imposing a short-term cognitive and emotional burden, but it is not a measure of permanent damage or a universal estimate of productivity loss.
People who want to protect uninterrupted reading time can reasonably consider silencing nonessential notifications.
The more important scientific lesson is that the way a phone demands attention may matter more than its simple physical presence.
Future research must establish how widely and how durably that distinction applies.
Related Research Today coverage examines research on quick-video rewards and interrupted studying and how social messages influenced collaborative learning intentions.
Source Information
Study title: The effects of smartphone presence during a reading task: a psychophysiological study
Authors: Júlia Loripe Guimarães, Raquel Byel Kim, Vinicius Panão Ferreira, Raymundo Machado de Azevedo Neto, Esaú Ventura Pupo Sirius, Shirley Silva Lacerda, Paulo Rodrigo Bazán and Elisa Harumi Kozasa
Journal: Scientific Reports
Publication date: 9 November 2026
Study design: Controlled three-condition psychophysiological reading experiment with questionnaires, EEG, ECG and eye tracking
Sample or scope: 36 WhatsApp users (mean age 22.54 years); no visible phone, visible silent phone and visible phone with active WhatsApp notifications
Key finding: Active notifications coincided with worse objective and subjective reading comprehension, higher anxiety and increased frontal beta-band EEG power; global EEG and eye-movement measures showed no significant differences
