New research published in Computers in human behavior It has been suggested that receiving a smartphone notification disrupts a person’s concentration for about 7 seconds. This study provides evidence that how often you check your phone and the amount of notifications you receive are better predictors of this distraction than your total daily screen time. These findings demonstrate that fragmented digital habits play a key role in how technology impacts human attention.
Previous experiments have shown that notifications impair task performance, but these studies often used artificial alerts that don’t reflect real-world conditions. Many past studies have also been unable to track the exact time of distraction or isolate the underlying psychological mechanisms.
The researchers wanted to separate out the different reasons why notifications attract attention. They aimed to determine whether people were simply distracted by the pop-up’s visual suddenness, a concept known as perceptual saliency. They also wanted to see if the distractions were due to study habits known as conditioning or the personal relevance of the messages.
“People receive a significant number of smartphone notifications every day (an average of more than 100 per day in our sample). It is well established that notifications can automatically grab attention, but the cognitive mechanisms underlying this capture and why some individuals are more vulnerable than others are unclear. “Little is known about whether this is the case. Our goal was to better understand both the mechanisms involved and the individual differences that may explain this sensitivity,” said study author Hippolyte Fournier, a postdoctoral researcher at the Department of Psychology at the University of Lausanne.
For the study, scientists recruited 180 college students with an average age of about 21 years. Participants were randomly assigned to one of three experimental groups. All participants completed the Stroop task, a classic psychological test that measures mental processing speed and concentration.
During the Stroop task, words representing colors appear on the screen, but the font color does not match the word itself. For example, the word “blue” may be printed in red ink. Participants must ignore the written text and identify the color of the font, which requires intense mental effort. While participants completed this task, researchers displayed smartphone-style notifications on their computer screens.
Scientists used deceptive settings to make the experience feel real. In the first group, known as the personal notification group, the researchers used a cover story to convince 60 participants that their smartphones were syncing with their computers. This setting led participants to believe that the pop-ups they saw during the task were actual personal messages.
A second group of 60 participants saw clear and realistic social media notifications, but they knew the messages were from someone else. This dummy notification group allowed researchers to test the effectiveness of learned habits, eliminating the element of personal relevance. The final group of 60 participants saw a blurry notification that popped up and moved like a regular alert, but contained no readable information.
This group of blurry notifications helped scientists isolate distractions caused purely by unexpected visual movement of objects. Before the experiment, participants completed a questionnaire measuring different types of anxiety, including social anxiety and fear of missing out. After the task, the researchers collected three weeks of objective screen time data from participants’ smartphones and tracked their daily usage patterns.
The researchers found that a single notification slowed participants’ cognitive processing by about seven seconds. Delays occurred in all groups, but were most pronounced in the personal notification group. This pattern suggests that distraction is due to a combination of visual pop-ups, learned relevance to the phone, and the personal meaning of the alert.
Within the personal notification group, the degree of distraction depended largely on how relevant participants felt the notification was. Alerts that evoked a strong emotional response or a strong desire to see the content caused delayed reaction times. The researchers also used an eye-tracking device to track participants’ pupil dilation during the task.
Pupil dilation is a physiological response that usually indicates increased arousal or deep mental effort. Scientists observed changes in pupil size that reflected behavioral delays. This provides evidence that emotion-related notifications cause measurable physical responses in the body.
By analyzing daily smartphone habits, the scientists found that total screen time was not a strong predictor of participants’ level of distraction. Instead, the number of notifications a person typically receives each day and how often they check their phone were stronger predictors. Participants who tended to have highly fragmented phone habits experienced the most severe attentional disruptions.
“Our findings suggest that notifications can disrupt cognitive processing for approximately 7 seconds, and that this disruption reflects multiple mechanisms, including perceptual salience, learned conditioning through repeated exposure, and their potential social relevance,” Fournier told PsyPost.
“Importantly, we found that beyond total screen time, the number of notifications received and the frequency of checking smartphones were associated with stronger disruption effects. This suggests that disaggregated smartphone use, not just overall screen time, may play an important role in how digital technology affects our attention.”
“While the delays we observed may seem small in isolation, their significance depends on how frequently notifications occur in daily life. Even short interruptions, when repeated dozens or hundreds of times a day, can have a significant impact on concentration and productivity. Therefore, their practical significance lies in their cumulative impact.”
Surprisingly, the primary personal notification group did not show a clear association between anxiety levels and degree of distraction. The data suggest that when notifications are viewed as positive or personally appealing, general anxiety does not significantly alter levels of distraction.
The researchers note that there are several limitations that should be kept in mind when interpreting these findings. Pupil dilation can be affected by physical movement or changes in screen brightness. This means that physiological data contains natural variation. Because notifications tended to be perceived as pleasant in this study, the experiment may not have fully captured how anxiety interacts with negative or threatening digital messages.
Scientists also caution against misinterpreting these findings as a sign that all social media use should be strictly prohibited. The goal of this research is to encourage more mindful and adaptive technology habits, rather than avoiding technology altogether.
“Given the intense public debate about social media use, our findings should not be interpreted as suggesting that social media or notifications should be avoided completely,” Fournier explained. “Rather, they highlight the importance of a deeper understanding of the cognitive mechanisms involved in order to promote more balanced and mindful use, especially for individuals who may be more vulnerable to attentional interruptions. The goal is not prohibition, but informed and adaptive use.”
Future research will examine how notifications became so attention-grabbing over time. Scientists also plan to investigate whether frequent social media use changes a person’s ability to stay focused on long-term goals. Another area of planned research involves understanding why people engage in repetitive scrolling behavior and how it relates to everyday emotional regulation.
“One of the challenges in this field is that it is difficult to study the actual effects of notifications (or social media use) on cognition in a laboratory setting while maintaining experimental control,” Fournier said. “In this study, we used a cover story that allowed us to measure the effectiveness of participants’ actual notifications in a controlled environment. This approach opens a promising avenue for future research aimed at studying digital behavior in a more ecologically valid manner.”
The study, “Attention Hijacked: How Social Media Notifications Disrupt Cognitive Processing,” was authored by Hippolyte Fournier, Arnaud Fournel, François Osiurak, Olivier Koenig, Flora Pâris, Vivien Gaujoux, and Fabien Ringeval.
