How too much screentime affects brain health

 

Shot of a young woman using a mobile phone in her bed. [Getty Images]

Mildred Injera, 35, exemplifies how deeply smartphones have woven themselves into modern daily life. She rarely ventures outside her home, particularly during chilly weather, opting instead to devote countless hours to scrolling through platforms like TikTok, WhatsApp and Instagram purely for entertainment.

“As long as I have internet and my phone is working, I’m set for the weekend. Even on weekdays, screens bring me joy,” Injera shares. Her reliance on her device has grown so strong that she often neglects real-world interactions with neighbours, friends and family.

She admits that her phone frequently steals time she needs to cook, make essential calls, or keep up with personal commitments, such as attending weddings or family events. “I’m always setting reminders on my phone because I know I’ll forget to attend events or honour schedules,” she explains.

This habit also has financial consequences. Injera spends much of her income on data bundles to stay connected, sometimes even taking small mobile loans just to buy airtime and keep up with online trends and conversations.

“It doesn’t bother me to take loans just to stay online. That’s what satisfies me. I’d rather be on the internet, keeping up with what’s happening, than eat a meal,” she confesses.

Injera’s story is far from unique; it reflects a wider trend in the digital age, where screens dominate work, education, socialising and leisure. Many people now spend several hours daily on smartphones, computers, and televisions.

Yet, health experts warn that this surge in screen time is quietly affecting brain health, contributing to shorter attention spans, reduced concentration and a phenomenon increasingly called “brain rot”, a gradual decline in mental sharpness, focus, and drive.

Dr Karen Blackmon, a consultant neuropsychologist at Aga Khan University’s Brain and Mind Institute in Nairobi, notes that today’s digital environment is designed to captivate users by hijacking the brain’s reward system.

“Screens are part of our daily lives because many of us rely on them for work. The challenge arises when the same devices used for work also become our main source of entertainment and pleasure, especially through social media,” Blackmon says.

She explains that platforms are intentionally designed to trigger pleasure responses, making it hard to disconnect. The brain’s reward system, which evolved to reinforce survival and social behaviors, releases feel-good chemicals like dopamine when we are rewarded, such as receiving praise from a parent or teacher in childhood.

Social media mimics this process: likes, comments and notifications create similar dopamine surges, encouraging repeated engagement. While dopamine naturally supports motivation and pleasure, rapid digital hits can trap users in a cycle of chasing fleeting gratification.

“We get a quick hit of dopamine from notifications or likes, but the feeling is short-lived,” Blackmon says. “This keeps us checking for more, much like patterns seen in addictions such as smoking or drinking.”

Constant interruptions from notifications and switching between apps rewire the brain for instant rewards, making sustained attention harder. Tasks that require prolonged focus, studying, deep reading, or complex projects become increasingly difficult. Excessive screen time also affects emotional health.

Relying on online validation can trigger anxiety or disappointment when expected responses don’t appear, potentially leading to stress, low mood, or depression. This effect worsens when people abandon offline activities that stabilise mood, like exercise, face-to-face socialising, or time in nature.

Not all screen use is harmful. Purposeful digital activities, learning new skills via tutorials, creating content, or engaging in meaningful communication, can boost cognition and creativity. The problem lies in passive, endless consumption; mindless scrolling or binge-watching without intent. “If someone watches a YouTube tutorial and learns a new skill, it can stimulate the brain’s creativity,” Blackmon notes.

Fleeting gratification

“But passive scrolling can trap the brain in a cycle of quick rewards. It’s crucial to distinguish between healthy and unhealthy technology use,” Blackmon emphasises. Many people sacrifice sleep for late-night scrolling, disrupting rest, while starting the day with phones floods the mind with stimulation, reducing mental clarity.

Blackmon recommends morning sunlight to reset circadian rhythms and suppress lingering sleep hormones. Evening exposure to blue light from screens lowers melatonin, the hormone regulating sleep, so the brain needs darkness and calm for proper rest. Signs of emerging “brain rot” include persistent concentration struggles, chronic stress, loss of enjoyment in routine activities, compulsive phone-checking, and disrupted sleep.

Fortunately, the brain’s neuroplasticity allows recovery. Positive habits, regular screen breaks, outdoor time, exercise, in-person socialising, reading, and consistent sleep can reverse the damage.

Blackmon advises limiting passive entertainment to short sessions, perhaps an hour daily and taking movement breaks every 60–90 minutes during work.

Beyond limiting screen time, active cognitive engagement is essential. Planning events, managing finances, reading physical books, or learning new skills all help strengthen mental resilience.

“Challenging projects stimulate the brain in healthy ways. The best approach is to take on meaningful challenges with others, whether planning a social event, working on a project, or learning something new,” she advises.

Movement breaks

Dr Catherine Syengo Mutisya, a consultant psychiatrist, highlights global trends showing that countries like Sweden and Finland—once pioneers in digital education—are returning to pen-and-paper methods in primary schools over concerns about declining concentration and learning outcomes from excessive screen use.

“In psychology, we see that writing by hand activates the brain differently. Transferring thoughts from mind to paper engages cognitive functions more fully,” Mutisya explains.

She links rising attention issues, including ADHD-like symptoms, to heavy screen and social media use, a problem intensified during the Covid-19 pandemic when remote learning was widespread.

“During COVID-19, people relied heavily on digital platforms, including universities that moved most classes online. While technology enabled learning, prolonged screen time has affected concentration and socialisation,” she notes. Online interactions often create a false sense of connection, failing to replace physical presence and increasing feelings of loneliness.

Mutisya warns against over-relying on AI for quick answers, as it can bypass deep thinking and creativity developed through real-world problem-solving and face-to-face interactions.

“Technology is a great innovation that has brought solutions, but screen time needs to be balanced for everyone, regardless of age,” she stresses.

She recommends strict limits—no more than one hour of recreational screen time for children, with adjustments depending on purpose. Excessive use displaces exercise, socialising, and active movement. Working from home can worsen these issues, lacking the incidental social interaction and mental stimulation of commuting to an office.

Mutisya urges intentional breaks and disconnection after work. For professionals and students, multitasking with social media during tasks undermines both productivity and relationships.

Pediatrician Dr Michael Rich, director of the Center on Media and Child Health at Boston Children’s Hospital, highlights how developing brains form and prune neural connections, noting that digital media provides weaker stimulation than real-world experiences. He stresses the importance of a balanced mix of online and offline activities, including allowing boredom to nurture creativity and imagination.

Experts agree that setting mindful boundaries and cultivating enriched offline lives can restore mental clarity and well-being in today’s screen-saturated world.