A new study published in NeuroImage has found that individuals who often interact actively with short video platforms may experience subtle reductions in their ability to maintain alertness. The researchers found that high levels of active short video use—such as liking, commenting, or switching between content—were linked to decreased performance on tasks that require staying alert to sudden signals. This association appeared to be connected to how two brain systems communicate while at rest.
The widespread use of short videos on platforms like TikTok and Instagram Reels has transformed how people engage with media. These videos are short, fast-paced, and often embedded in personalized content streams. Many users interact with the content by commenting, sharing, or reacting in real time, behaviors the researchers refer to as “active usage.” Others watch videos without much interaction, termed “passive usage.”
Past studies have raised concerns that frequent social media use might weaken sustained attention or increase distractibility. But much of this research focused on general media use, not short video platforms specifically. The authors of the current study wanted to explore how different types of short video engagement might influence distinct components of attention.
They also aimed to understand how such behaviors might be reflected in brain connectivity. Their goal was to pinpoint whether there is a measurable “cost” to engaging frequently with short videos in an interactive way.
“When we designed this study, we noticed that most research on social media had focused on platforms like Facebook, which are still largely text-driven. Short-form video platforms, however, are a newer, highly visual type of social media that rely on algorithmic, personalized recommendation, so existing findings may not automatically generalize to this context,” explained study author Guanghui Zhai of Tianjin Normal University.
“At the same time, people in everyday life are already asking, ‘Are short videos destroying our attention?’, but it is unclear whether all usage patterns carry the same risk. Building on prior work that distinguishes active from passive social media use, we applied this idea to short videos and focused on behaviors such as liking, commenting, and sharing.”
“We were especially interested in whether this active style of engagement places different demands on the brain than simply watching, and in the almost unexplored question of how everyday short video habits relate to specific attention functions—particularly the alerting system—and to the underlying brain networks that support it.”
The research involved two related experiments. In the first, the researchers studied 319 participants who completed a detailed questionnaire on their short video usage. The questionnaire distinguished between active behaviors like commenting or liking videos and passive behaviors like simply watching without interacting. Participants also completed the Attention Network Test, a behavioral task that measures three key components of attention: alerting, orienting, and executive control.
The alerting component reflects the ability to maintain a state of readiness to detect sudden events. The orienting component involves shifting attention to specific locations or cues. Executive control refers to the ability to resolve conflicts between competing stimuli. During the test, participants responded to arrows presented on a screen, with varying cues and distractions, and their reaction times were recorded.
The results showed that participants who engaged in high levels of active short video use tended to perform worse on the alerting component. Specifically, they showed less improvement in reaction time when given a cue to expect a target, which suggests lower readiness to respond. This pattern was not observed for passive users.
The orienting component showed a small effect, where passive usage was linked to slightly better performance, but only among users who engaged in low levels of active use. No clear relationship emerged between short video use and executive control.
“In our data, people who more frequently engaged in active short video behaviors (for example, liking and commenting while watching) tended to show lower efficiency in the ‘alerting’ part of attention—the basic readiness to detect and respond to sudden signals,” Zhai told PsyPost. “This pattern did not appear for passive watching to the same extent.”
To better understand these behavioral findings, the researchers conducted a second experiment using brain imaging. They invited 115 of the original participants to complete a resting-state functional MRI scan. This type of scan measures how different parts of the brain communicate when a person is not doing any specific task.
The researchers focused on the brain’s default mode network and executive control network. The default mode network is typically active during self-reflection and internal thoughts, while the executive control network supports goal-directed behavior and attention.
They analyzed the data to see whether active or passive usage predicted patterns of connectivity between brain regions. One connection in particular stood out: between the right ventral prefrontal cortex, a region involved in evaluating important signals, and the right posterior cingulate cortex, a key hub in the default mode network. Participants with higher levels of active short video use showed stronger connectivity between these two areas. This connection also statistically explained the link between active usage and lower alerting efficiency, meaning it acted as a mediator.
“One thing that surprised us was how right-lateralized the key functional network turned out to be, and how strongly it was embedded in the default mode network,” Zhai explained. “We found that the critical pathway involved a right-hemisphere circuit linking the ventral prefrontal cortex and the posterior cingulate cortex—regions that sit at the intersection of detecting salient events and managing internal, self-related processing. This pattern suggests that the ‘cost’ of very active short video use may lie in how the brain balances internal social–emotional processing with readiness to respond to external signals.”
“The effects we found are modest but reliable at the group level, with standardized regression coefficients in the small-to-moderate range. This means we are not talking about dramatic impairments that you would notice immediately in everyday life, but rather subtle differences that become clear when we test many people with sensitive behavioral and brain measures. In other words, heavy active use of short videos is unlikely to ‘destroy’ attention on its own, but it may nudge the alerting system in a less efficient direction, especially when combined with other demands on attention and sleep.”
“At the same time, many studies have also shown that social media use can enhance subjective well-being and, in some cases, help relieve anxiety and depressive symptoms, largely through opportunities for social connection,” Zhai continued. “So from a practical standpoint, our findings support a message of moderation: short-form video is not inherently harmful, but very intensive and highly interactive use may come with small attention costs that need to be balanced against its potential benefits.”
“For the average user, the message is not that short videos are “purely bad,” but that very interactive, multitasking-style use may subtly tax the brain systems that help us stay alert.”
As with all research, there are limitations. Importantly, the study was correlational and cross-sectional, meaning it measured variables at one point in time. As a result, the researchers cannot say for certain whether active short video use causes reduced alerting, or whether people with lower alerting efficiency are more drawn to active use. The sample also consisted primarily of young adults in China, so the findings may not generalize to other age groups or cultural contexts.
Despite these limitations, the study contributes to a growing body of research exploring how digital media use intersects with core cognitive functions. By identifying a specific brain connection that may underlie reduced alerting among frequent active users, the researchers offer a starting point for future work aimed at understanding and potentially mitigating attention-related effects of short video engagement.
“Our next steps are to move beyond correlations by combining longitudinal and experimental designs,” Zhai said. “For example, we would like to track people’s short video behavior over time using objective logs, manipulate how often they engage in active versus passive use, and examine the consequences for attention, sleep, and mood.”
“We are also interested in testing whether simple ‘digital hygiene’ strategies—such as limiting active interactions before bedtime or during study time—can help protect the alerting system. Ultimately, we hope to provide nuanced, brain-based guidelines for healthier media habits rather than a blanket message to avoid short videos.”
The researchers hope their findings can inform the design of digital platforms and help users make more informed decisions about how they interact with media. For example, limiting active engagement during tasks that require high alertness—such as before driving or while studying—may help preserve attentional readiness.
“One message I would emphasize is that the same behavior can have both benefits and costs,” Zhai said. “Active short video use can foster social connection and a sense of being heard, but our data suggest that this comes with a small ‘sacrifice’ in the brain systems that keep us alert to the outside world.”
“By identifying a specific brain pathway linking active use to alerting—the functional connectivity between the right ventral prefrontal cortex and the right posterior cingulate cortex—we hope to show that these trade-offs are real, measurable, and grounded in everyday habits. Recognizing them can empower users to make more informed choices about when, how, and how much they engage with short videos.”
The study, “The sacrifice of alerting in active short video users: Evidence from executive control and default mode network functional connectivity,” was authored by Guanghui Zhai, Yang Feng, Xin Ling, Jiahui Su, Yifan Liu, Yiwei Li, Yunpeng Jiang, and Xia Wu.
