A strange TikTok trend called 'sludge content' has Gen Z hooked. Here's what you need to know.

• TikTok has a mindless new obsession called "sludge content."
• The content is usually two or more unrelated videos cropped together.

Gen Zers, already known for being overstimulated, are fixating on a TikTok trend that is making them even more so.

Multiscreen videos, dubbed "sludge content," have been sweeping the platform. Creators make them by cropping together at least two unrelated clips. The result is disorienting, but some users can't get enough.

In response to a video of at least 10 overlaying clips, one user said: "My mind feels whole."

However, not everyone agrees the videos are soothing. Some argue the new trend is irritating. Commenting on an explainer video, one user said: "This is all I get and I'm so over it!!!"

Several creators on the platform are mocking the trend for being Gen Z-specific.

Meme videos shared on the platform show people trying to retain younger people's attention by holding screens showing the "Subway Surfers" game. One video, which is captioned, "When you're pitching and start losing the Gen Z crowd," shows a man holding a laptop screen featuring the game playing while he presents.

As well as "Subway Surfers," common clips used in sludge videos include screen recordings of various smartphone games and the TV show "Family Guy."

The origin of the videos is unknown but some think they keep viewers watching content for longer. TikTok's algorithm appears to prioritize videos that have a longer retention time, meaning the longer a video is watched the more overall views it is likely to get.

The idea is that if a viewer gets bored with one clip, they might turn their attention to the other. Others just put the new trend down to mindless escapism.

Andreas Schellewald, a doctoral researcher of social media at Goldsmiths, University of London, told NBC News: "It functions as something playful, that can take your mind off things and doesn't require you to dive deep."

"You can sit there and watch things unfold in front of your eyes," she said.