[Column] Short-form video addiction rewires and deteriorates the brain
How much short-form video content do we watch?
A 2024 survey of 1,000 Koreans aged 15 to 59 (2024 Digital Lifestyle Report, Mezzo Media) found that respondents spend an average of 44 minutes per day watching short-form videos. Teenagers had the highest viewing time, averaging 64 minutes per day. On a monthly basis, this translates into 52 hours per person. The trend is not unique to Korea: in China, the short-form video audience surpassed 1 billion in 2024, with viewing accounting for 95 percent of all internet use. In the United States, usage varies by state, but averages stand at 55 minutes per day on TikTok, 49 minutes on YouTube Shorts, and 33 minutes on Instagram Reels -- adding up to more than two hours daily (ZapCap, 2025).
As viewing times rise, so does the risk of addiction, making short-form video addiction an emerging social issue (Neuroimage, 2024). Research links it to insomnia, impaired learning and memory, visual deterioration, emotional regulation difficulties, and mental health issues such as depression and anxiety. These effects are particularly pronounced in children under 10 and adolescents.
What impact does heavy viewing have on the brain?
Although research is still developing, recent findings point to significant brain changes proportional to viewing time. Attention span shortens, concentration deteriorates, and both learning and memory weaken. After about an hour of viewing, individuals tend to recall only the most recent content, struggle to remember material from just minutes earlier, and have difficulty retrieving and explaining what they saw. In short, the brain’s ability to organize and store visual memories for later use declines.
Emotional processing is also affected. Short-form viewing primarily activates instinctive, one-dimensional emotions while reducing empathy, emotional understanding, and the ability to anticipate others’ reactions. Emotional control diminishes as well, leading to more frequent episodes of anger, irritability, and disproportionate despair or frustration. These effects are linked to reduced activity in the prefrontal cortex and weakened connectivity with the amygdala, impairing impulse control and regulation of negative emotions.
Among adolescents with signs of addiction, lethargy and reduced motivation emerge. They adapt passively, preferring automatically provided content over active pursuits. Experiences of deep engagement or strong emotional impact become rare, and perceptions grow shallow and superficial. This reflects changes in the brain’s reward circuitry, which becomes attuned only to the immediate rewards of video viewing. Dopamine release fails to occur appropriately in response to other forms of stimulation.
By contrast, long-form content -- such as films, dramas, or longer YouTube videos -- benefits the brain. It triggers higher levels of neurotransmitters like dopamine, serotonin, and adrenaline, activates the empathy network, and enhances sensitivity to subtle emotional cues after viewing.
Whereas short-form content fragments our experience of the world, reading or watching films fosters the ability to follow complex narratives and consider issues from multiple perspectives. For the health of our brains, moderation is key. After all, our lives are not short -- they are long.
Chang Dong-seon is the CEO of Curious Brain Lab and resides in Seoul. He studied Biology at Uni Konstanz, Neuroscience at the International Max Planck Research School, and Cognitive Science at Rutgers University. Chang's career includes roles as an Assistant Professor at Hanyang University and a Researcher at the Max Planck Institute for Biological Cybernetics. He also served as the head of the Future Technology Strategy Team at Hyundai Motor Group. His extensive expertise spans biology, neuroscience, and cognitive science. This column was originally published in Segye Ilbo in Korean on Aug. 13. -- Ed.