Why TikTok Is So Addicting? (2024)

Using neuroscience to deconstruct what makes TikTok so addicting

Eliza Aguhar

8 min read

It’s no secret that there’s a relationship between the human attention span and modern technology. A study enlisted by Microsoft in 2015 found that the average human attention span is now 8 seconds.

I’ll repeat that: our average attention span is 8 seconds.

(I’m lucky if I haven’t lost you yet.)

According to Philipp Lorenz-Spreen, a Postdoc at the Max Plank Institute for Human Development, “Content is increasing in volume, which exhausts our attention and our urge for ‘newness’ causes us to collectively switch between topics more regularly.” In other words, the more content we’re faced with, the less our attention span is and the greater our urge is to look at new content.

More than that, a study done by the UC Berkeley Haas School of Business found that our brains reward ourselves for absorbing information the same way our brains reward ourselves from eating good food or earning money.

We have an internal reward system; when we get things we crave (like eating cake, for example), our brains release a neurotransmitter called dopamine, allowing us to feel pleasure and satisfaction as a reward for fulfilling our craving.

Dopamine essentially creates a reward-seeking feedback loop:

We crave something that gives us pleasure → we actively seek it out to feel that rush of dopamine again → we’re rewarded for getting the thing we crave → the dopamine wears out → and the cycle continues

Dopamine is the reason we feel motivated and affects our mood, sleep, memory, learning, and concentration, and according to UC Berkeley Associate Professor Ming Hsu, why we are curious.

“To the brain, information is its own reward, above and beyond whether it’s useful,” Hsu stated when asked about his findings. “And just as our brains like empty calories from junk food, they can overvalue information that makes us feel good but may not be useful — what some may call idle curiosity.”

But not all information is held equal. I’m not talking about the context of the information; I’m talking about how it’s presented to us.

To put it plainly, we are very visual. Motion attracts our attention because it helps us survive. We are hardwired to pay attention to motion because it’s the difference between living and being eaten by a bear or being run over by a car. It’s the reason why 5 billion YouTube videos are watched per day and the average American only reads for an hour and a half per year.

So, what do our brains deem as worth our attention?

To summarize and simplify, short videos. And lots of them.

If we were to summarize how to keep the human attention span, it may look something like this:

Short and engaging videos + large amounts of content = my attention

Knowing this, it’s no coincidence that TikTok is popular. The average length of the top 100 TikTok’s in 2019 was 16 seconds.

Even though the maximum length for a TikTok is 60 seconds, the most successful TikToks are only a third of that length. And with more than half of all TikTok users uploading videos and 1 billion videos viewed every day, there’s no shortage of content on the platform.

But this begs another question: with all that content, how does TikTok ensure that we only see the content that we like? Won’t we lose interest quickly because we can’t find content that satisfies our dopamine craving? How does TikTok sort through all those videos?

On TikTok, the ‘For You’ page is where the coveted TikTok algorithm curates the best TikToks (you guessed it!) for you.

Like any other recommendation list (like YouTube or Netflix), the For You page uses analytics from other videos you like to automatically queue an endless stream of videos for you to enjoy.

TikTok does this using machine learning, a subset of AI, to automatically learn which videos you appear to enjoy the most. The model evaluates every video uploaded and determines the probability that you will enjoy it using classification information (also known as labels) in the form of hashtags. Like all AI, the model becomes more accurate the more you train it. In other words, the more your watch, like, comment, share, or save TikToks with a certain hashtag, the machine learning model will better predict the videos you are most likely to enjoy.

Let’s say you really like videos of cute dogs (again, who doesn’t), so you only watch and like videos tagged #dogs. The machine learning model then takes this data and compares it to a newly uploaded video. If the video is labeled #dogs or another hashtag similar to it, the machine learning model can predict a high probability that you will like that video and queue it in your For You page.

Every now and then, a video with a trending hashtag will appear on your For You page to see whether enjoy videos tagged with different things. If you start watching and liking them, the machine learning model improves (or learns) and starts curating videos based on these new parameters.

Using AI and machine learning to optimize recommended videos isn’t something new, though — YouTube and Netflix do the same thing by using information from the videos, movies, and TV shows you search for and watch.

What’s different about TikTok is that it takes away your ability to choose which recommended video you see next.

Choice overload is a term coined by American writer and businessman Alvin Toffler which describes a situation where people are confronted with many similar choices, which causes them to be unsure and frustrated about which option to pick.

Ever wonder why you’re sometimes overwhelmed about which cereal to pick when there are dozens of options at the grocery store?

Yeah, that’s choice overload.

The idea of being conflicted on which cereal is best worth your money is similar to being conflicted on which TV show is best worth your time.

After you’re finished watching a video on YouTube or show on Netflix, you’re faced with a plethora of options on what to watch next. And because machine learning is used to curate recommended videos, chances are they’re all pretty similar, making it more difficult to choose which thing to watch next.

Unlike TikToks, content on YouTube or Netflix lasts significantly longer. Once you choose the next thing to watch, there’s a longer commitment to how long you are going to watch. So instead, faced with choice overload, you spend longer staring at all the thumbnails, trying to decide how you’re going to entertain yourself for the next 10 to 60 minutes.

TikTok takes the opposite approach. By automatically queuing the AI-curated videos on you For You page, as soon as your attention span has been exhausted on a video, a simple swipe up lets you move onto the next video. Don’t like that video? Not a problem — they’re short enough so you can swipe onto the next one without the same feeling of commitment as something on YouTube or Netflix. Plus, the machine learning model has more data on the types of videos that you like and the types of videos that you don’t. Taking away your ability to choose prevents you from experiencing indecisiveness and choice overload. So instead, you keep watching curated TikToks.

The constant stream of TikToks covers all the bases on what’s worth our attention span: they’re short, they’re engaging, there’s a constant flow of them, and they’re the content we enjoy watching which causes our brains to release dopamine, encouraging us to watch more videos. The combination results in hours on TikTok because your brain can’t seem to get enough of the dopamine rush.

An integral part of TikTok’s success is that it capitalizes on how humans are evolving because of modern technology. We like the path of least resistance, and that’s exactly what TikTok is giving to us — it’s formulated to work alongside our internal rewards system.

The type of content you see on TikTok isn’t revolutionary. We’ve all seen dances, lip-syncing, comedy skits, and other types of funny videos. But, TikTok presented it in different packaging, making it more attractive to its audience.

So, what makes TikTok addicting?

🔑 The videos are short enough so that it doesn’t exhaust our attention span but long enough to give TikTokers creative freedom;

🔑 The use of machine learning to curate videos that each unique user would enjoy gives viewers a dopamine rush when they watch a video;

🔑 An endless queue of curated videos minimizes the effects of choice overload and to prolong the dopamine rush caused by watching TikToks.

TikTok is a form of media content evolving with its audience. The same way that television disrupted radio and streaming disrupted cable TV, will TikTok revolutionize the way that we watch our entertainment?