Excessive Smartphone Use May Significantly Impact Cognitive Function and Mental Health
A groundbreaking study suggests that overusing smartphones and other electronic devices can have serious effects on our mental well-being and cognitive abilities. Conducted by researchers from the Universities of Alberta, Georgetown, Texas, Boston, and British Columbia, this study, recently published in PNAS Nexus, also highlights a potential remedy: disconnecting from electronic devices, even for short periods, can yield mental health benefits comparable to those provided by clinical therapies commonly used to treat mental health issues.
The Investigation and Its Findings
This month-long, randomized, controlled clinical trial aimed to explore how a consistent inability to access the internet via smartphones—blocked through a specialized mobile app—might influence cognitive functioning and psychological health. The core question was whether digital deprivation could produce measurable benefits.
A total of 467 participants were enrolled and divided into two groups. One group was prohibited from connecting to the internet for two weeks to assess how such deprivation could affect various psychological variables. The control group maintained their usual, unrestricted internet access, which allowed the researchers to objectively monitor adherence. The experiment was challenging for participants; out of those who agreed to install the app designed to block web access, only 266 succeeded, and just 119 managed to abstain from using the internet or keep the restriction active for a minimum of 10 days.
Among those who adhered to the restriction, the results were telling. The intervention not only cut average daily internet use from 314 minutes to 161 minutes but also led to notable mental health improvements. Specifically, participants showed significant gains in attention span—reversing a decade-long decline associated with aging—and 91% reported improvements in at least one area of mental health.
Participants also experienced higher life satisfaction, decreased depressive symptoms, and enhanced concentration. These positive outcomes are attributed to increased face-to-face social interaction, more time spent on physical activity, and greater engagement with nature. Additional benefits included a heightened sense of control over one’s behavior and better sleep quality.
While only about a quarter (25.5%) of participants fully complied with the two-week internet ban, even those who partially adhered reported substantial mental health improvements. This suggests that even a reduction in internet usage can be beneficial, reinforcing the idea that complete disconnection isn’t always necessary to see positive effects.
Implications and Recommendations
The researchers posit that cutting back on internet and smartphone usage could produce effects similar to, or even surpassing, those of antidepressant medications used in treating certain mental health conditions. This highlights the importance of moderating screen time and adopting strategies to disconnect periodically.
They advocate for the development of partial disconnection strategies—such as limiting social media access or establishing offline intervals—as practical tools to promote healthier lifestyle habits without fostering dependence on digital devices. Such approaches could serve as effective ways to balance the advantages of digital connectivity with the equally important need for authentic personal relationships and passions.
In conclusion, reducing screen time and limiting digital engagement may serve as powerful, accessible tools to improve mental well-being and cognitive health, potentially offering a natural alternative or complement to pharmacological treatments.
Source
Castelo N, Kushlev K, Ward AF, et al. “Blocking mobile internet on smartphones improves sustained attention, mental health, and subjective well-being.” PNAS Nexus, 2025, Volume 4, Issue 2, pgaf017. Doi: https://doi.org/10.1093/
