Separation From Your Cellphone Boosts Your Cognitive Capacity

Separation From Your Cellphone Boosts Your Cognitive Capacity

By Carolina Kuepper-Tetzel

In a recent weekly digest, we explored the pros and cons about cellphones in the classroom. In today’s blog post, I would like to contribute to that discussion by presenting a new research study that looked into the effects of the mere presence of one’s cellphone while performing cognitive tasks (1). The findings of Ward et al.’s (1) experiments are intriguing and bear important practical implications. Let’s dive in and see what they did in their study, shall we?

Cellphone presence and cognitive capacity

The researchers used a simple and straight-forward study set-up. They invited students to participate in an experiment where students were randomly assigned into one of three conditions.

  • In the "other room" condition, students were asked to leave their belongings (including their cellphones) in the lobby before coming into the room where the experiment would take place.
  • In other two conditions, students were asked to take their belongings with them to the experiment room, and were either told to leave the cellphone out of sight, e.g., in their bags or pockets (bag/pocket condition) or place it face down on the desk within sight (desk condition).
Image from Pixabay

Image from Pixabay

All participants were asked to make sure to put their phones on silent with vibration deactivated. Then, participants worked on two cognitive tasks: One working memory task – called Automated Operation Span task (OSpan) – where people are asked to actively process information while holding other information in mind. For this specific task, they have to solve math equations while remembering random letters in the order presented. For the other task – the Raven’s Standard Progressive Matrices (RSPM) – participants had to identify the missing piece in a matrix pattern. This test is used to assess fluid intelligence and your performance depends to a large extent on the available attentional capacities to identify the underlying rule of the pattern matrix. Thus, both tasks are cognitively demanding and require people’s full attention. Consequently, any disruption in attention or additional process that takes away attention capacity harms performance in these tasks.

The researchers wanted to test the hypothesis that the mere presence of one’s own cellphone in immediate sight or reach would eat up attentional resources. They had two reasons in mind why this could be the case:

a) People may consciously draw attention and orient themselves towards the cellphone. Maybe thinking about what they are missing out on while doing the task at hand.

b) People may unconsciously inhibit automatic attention to the cellphone. The idea here is that the cellphone may attract automatic attention, but inhibition processes – which cost attentional resources – damp the orientation towards the desired object. Importantly, the authors argue that people are not aware of these inhibition processes, but they nevertheless can lead to decreased performance in cognitively demanding tasks.

What did they find?

Indeed, having one’s cellphone in sight (desk condition) led to lower cognitive capacity in both tasks (see figure) compared to the condition where the cellphone was in a different room (other room condition). If the cellphone was out of sight, but within immediate reach (bag/pocket condition), the results were more mixed: Here the researchers sometimes found a significant difference to the “other room” condition, but not always.


In order to explore if participants were consciously distracted by the cellphone and thinking about it (explanation a), the researchers asked all participants “While completing today’s tasks, how often were you thinking about your cellphone?” Participants reported that they had not been thinking about their phones at all. Thus, a verbalizable and conscious process harming the performance may not be the key to the finding. The more likely explanation for these effects is that automatic processes (maybe inhibition of automatic attention) are responsible for the detrimental effect of cellphone presence on cognitive capacity.

Image from Pixabay

Image from Pixabay

Cellphone dependence as moderator

In a follow-up experiment, the researchers looked at whether people who reported to be more dependent on their cellphone (“I would have trouble getting through a normal day without my cellphone.”) would experience stronger negative effects of having it within sight. Indeed, that is what they found – and this finding bears important practical implications.

Let me break down the findings more concretely:

  • For people who reported a strong dependence, putting the cellphone in the bag or leaving it in another room made a tremendous difference for their cognitive capacity: They performed much better in these two conditions compared to the one where the phone was on the desk.
  • For people who reported a weaker dependence, it made no difference where the phone was. Thus, their performance was not affected by the location of the phone.

Interestingly, the results stayed the same whether the cellphone was just on silent mode or completely turned off.

This is the first study that looked into the effects of mere cellphone presence and additional factors need to be taken into consideration in future research before drawing strong conclusions. However, it nevertheless is good food for thought and makes you reflect on how you may want to set up a good learning environment.  

Take home message for students

Image by Pixabay

Image by Pixabay

If you experience a high dependency on your cellphone, you will perform better on high-demanding tasks if you put away your phone so that it is completely out of sight. Quick fixes like putting your phone on silence, turning it completely off, or putting it face-down may not work as long as it is still in sight. Try to do leave the phone in your bag or in a different room. For example, when you are studying in the library it would be most natural to leave your cellphone locked away. To ease this process, you may want to do this as a group. For example, when you go to the library to study together, everyone leaves their phone outside and plan breaks where you go outside to engage with your phone.   

Take home message for teachers

As mentioned in the beginning, this research adds to the discussion whether to allow cellphones in the classroom or not. The authors point out that one key aspect may be that it should feel natural to students to be separated from their phones. Thus, if a there was a general school policy in place that invited students to leave their cellphones in dedicated lockers, it could work.


(1) 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, 140-154.