Short videos have become one of the leading sources of information and entertainment for internet users worldwide. Reflecting the scale of this trend, TikTok alone had an estimated 2 billion active users in 2025, spanning generations from Gen Z to older adults.

The cognitive implications of this phenomenon have been linked to brain rot, a term describing cognitive deterioration associated with the digital age. It is characterized by declining cognitive performance, attention deficits, and emotional desensitization resulting from prolonged exposure to low-quality digital content.

Frequent viewing of short videos has been associated with adverse psychological outcomes, including depression, anxiety, and problematic or addictive patterns of use. More recently, researchers have raised concerns that excessive use of short videos may selectively reorganize resting-state brain activity, with potentially harmful effects on cognitive and emotional functioning, particularly attention regulation and executive control.

Despite these concerns, fast-paced short-form videos are increasingly being incorporated into educational settings because they are believed to improve motivation and engagement of the users. However, this trend often overlooks conflicting evidence regarding their effectiveness for learning and the cognitive costs associated with their use, including poorer working memory, reduced verbal processing, and diminished activation of semantic networks.

Attention Processes

The brain has a limited capacity to process information at any given time. Attention acts as a vital filter and control mechanism, allowing neural networks to prioritize relevant data, suppress distractions, and direct energy to what matters most.

Attention is generally divided into two complementary processes.

• Bottom-up attention (stimulus-driven) is directed by external stimuli, automatically drawing attention to features that stand out because of their intrinsic properties.
• Top-down attention (goal-directed) is guided by prior knowledge, intentional goals, and voluntary control.

Neurophysiologic research has provided important insights into the neural circuits underlying both bottom-up and top-down attention. These studies showed that attention influences not only the average firing rate of neurons but also neuronal variability and the degree of correlation between neurons in specific brain regions.

Effects on Memory

A functional MRI study compared neural activity in 57 participants during memory retrieval after exposure to either short, fragmented videos or longer, continuous videos. Researchers analyzed changes in the blood oxygen level-dependent signal during a memory task to examine how short-form video viewing influenced cognitive retrieval. The findings suggested that fast-paced, fragmented content impairs memory by reducing neural coordination in the claustrum, caudate nucleus, and middle temporal gyrus (MTG) during memory recall, as follows:

• Participants who viewed short videos showed poorer memory performance, accompanied by reduced activation of the left claustrum, caudate nucleus, and MTG during memory retrieval, as well as weaker functional connectivity between the caudate nucleus and the claustrum.
• Reduced activation of the claustrum may reflect difficulty reconstructing a coherent mental representation during memory retrieval after viewing short videos. The researchers suggested that the continuous narrative structure of longer videos promoted the formation of more cohesive memory traces, allowing more efficient reconstruction of an integrated mental scene during recall.
• The caudate nucleus is a vital part of the brain’s prefrontal-striatal network. The caudate nucleus plays a central role in multiple cognitive processes. Reduced activation among participants who watched short videos may indicate impaired top-down attentional control and less effective goal-directed processing during memory retrieval.
• The MTG is crucial for semantic processing, lexical and conceptual retrieval, and the integration of multimodal information. Exposure to fragmented short-form videos reduced activation during memory retrieval and poor memory performance, suggesting that fragmented content interferes with deep semantic processing and contextual integration.

Taken together, these findings support the detrimental behavioral effects of fragmented short videos on memory and identify three potentially interconnected mechanisms: impaired information integration, reduced cognitive control, and disrupted semantic processing.

Participants who learned from short videos also showed significantly poorer immediate memory performance and experienced a higher rate of forgetting when explicitly asked to recall the material.

Short videos elicited greater neural synchrony in temporal and frontal regions associated with bottom-up attentional processing. Functional connectivity analyses further showed that exposure to short videos weakened communication among visual, attentional, and cognitive control networks.

Clinical Implications

• The widespread use of short-form videos on social media, characterized by rapid content shifts and constant fragmentation, has led to their increasing use in learning environments.
• Learning through short-form videos may impair memory by disrupting the brain networks involved in information integration, cognitive control, and semantic processing.
• Neurobehavioral studies suggest that viewing short-form videos on social media is associated with reduced neural synchronization during memory retrieval and poorer memory performance.

This story was translated from Univadis Italy, part of the Medscape Professional Network.