Shorts and Reels - Digital Cocaine for Our Brain?

Why we can’t stop – and it has nothing to do with weak willpower

Many people believe they are simply weak-willed when they catch themselves scrolling through Reels, Shorts or TikToks for too long again. But this is a mistake. The problem doesn’t lie in our character – it lies in our brain. More precisely: in a biological vulnerability that is systematically exploited by exactly these apps.

So why is it so much harder to concentrate on a book, be creative, practice an instrument or motivate yourself to exercise – but so easy to sink into a Reels frenzy? Why is it so hard for us to decide on a hobby that does us good in the long term – but so easy to stick with something that essentially leaves us empty? The answer lies in the brain. More precisely: in the way our reward system works with dopamine – and how differently it responds to quick stimuli and sustainable experiences.

Sometimes it’s frustrating: You actually want to do something that does you good. Continue reading a book. Finally start the sewing machine. Go jogging. And then you’re still sitting on the sofa, phone in hand, scrolling through Reels – and only notice it when half an hour has already passed. You don’t get addicted to Shorts because every video is so great – but because the brain teaches you in a sophisticated way to keep searching. How can it be that what strengthens us in the long term is so hard to start – and what leaves us empty is so easy to do?

Two Dopamine Pathways in the Brain

The answer lies, as so often, in the brain. More precisely: in the way it processes dopamine. Because dopamine – the reward hormone – is not only responsible for euphoria or motivation, but above all for a central question: “What was worth it – and what do I want again?” It works in two very different ways. One pathway is fast, impulsive and loves surprises. It responds to new things, stimuli, social signals, likes. The other pathway is slower, more patient. It activates when you stick with something, when you work concentrated, see progress, follow a plan (Douma and de Kloet 2020; Michaelsen and Esch 2021). One could say: One dopamine pathway calls “More of that!”, the other says “Good, keep going.”

The fast pathway: mesolimbic system

The first is the mesolimbic pathway – an evolutionarily ancient mechanism that ensures we store surprising positive events particularly strongly. So when we unexpectedly experience something good – a particularly funny video, a nice message or a viral hit – the brain releases dopamine so we remember: This action was worth it. But: The brain learns quickly. Next time, the dopamine release is no longer triggered by the event itself, but by the expectation that something good is about to happen. The reward shifts forward in time. So the dopamine peak occurs already when opening the app or on the first swipe (Ihssen and Wadsley 2021).

And now something paradoxical happens: When the actual reward – i.e., the next clip – then isn’t as good as hoped, the dopamine level even falls below the baseline. This is called a negative “prediction error” – the expected reward fails to materialize, and the brain responds with a small low (Wang and Wang 2025). This feels unpleasant. That’s why we swipe further. Not because the last video was so great – but because the brain wants to cover the disappointment as quickly as possible with a good experience. This is exactly how the scroll loop is created: Every swipe is an attempt to repair the dopamine low that has arisen from the disappointed expectation.

And this is a dangerous mechanism. Because unlike before – when reward was rare and you couldn’t order a ripe apple at the push of a button – you can swipe infinitely today. Each time with the feeling: Maybe the next clip is the one that makes me feel again what I felt the very first time.

The slow pathway: mesocortical system

In contrast, the mesocortical pathway works quite differently. It accompanies us when we read, build a piece of furniture or learn a new language. Here no quick euphoria arises, but a calm, stable feeling of progress, concentration and meaning. The dopamine release is smaller, but it carries us longer. This system activates when you stick with it, when you overcome, when you notice: “I’m growing with this task” (Fraser et al. 2022; Milbocker et al. 2024). The fast dopamine pathway is like refined sugar – sweet, quick, tempting, but in today’s dose completely unnatural and unhealthy. And just like with sugar, the low follows the kick. The slow pathway, on the other hand, is like a good, self-cooked meal: It takes time, it demands – but it satisfies and makes you content (Dresp-Langley 2023).

Those conditioned on dopamine from the fast pathway initially perceive slow activities – like reading, making music, writing, crafting, helping – as empty, bland or too exhausting (Dresp-Langley 2023). Fortunately, however, the brain is plastic. It can relearn. And the more we feed the slow pathway – with real, meaningful activities – the stronger it becomes. Then the book becomes more exciting, the conversation more fulfilling, the jogging round more motivating.

How Shorts Trick Our Reward System

A short clip. Two seconds of tension. Cut. Laugh. Continue. Maybe this time a cute puppy. Or someone falling on their nose while dancing. Or a life hack that looks like it could have saved your life – if you had watched it completely. What makes these formats so dangerous is not just their content – but what they do to our reward system. More precisely: how they trick it. Because actually this system is made to alert us to real opportunities: a ripe fruit, a rare find, a surprising moment of social closeness. Things that can’t be predicted, and therefore trigger a small fireworks in the brain when they occur: Dopamine. Learning. Repeating.

Shorts copy exactly this principle – just in highly concentrated, algorithmically optimized continuous loop. Every swipe movement is a promise: Maybe the next clip is funnier. Maybe more touching. Maybe exactly yours. But unlike in nature, where reward was rare and laborious, here the “button” is directly under our thumb. And that changes everything. Because we no longer wait for reward – we trigger it ourselves. And so often, until the system becomes numb.

With a movie there is a buildup. There is tension, silence, development, surprising turns. You dive in, have time to feel along, to go along. Sometimes a movie is also simply boring – and then you switch off. With Shorts it’s the opposite: If a video bores, you scroll on immediately. No buildup, no pause, no enduring. The next stimulus is always just one swipe away – and that’s exactly what binds. Because every further swipe is a small decision – and every decision keeps the reward system on alert.

The brain remembers: I can actively act here at any time to generate a good feeling. And because it occasionally succeeds, we stay with it. Even if the actual content has long been secondary. Even if the fun already stopped five videos ago. This principle is called variable reward – a strategy you also know from slot machines, Tinder swipes, loot boxes or online shopping. It’s always about the same trick: We don’t know when it will get good. Only that it might get good. And exactly this “maybe” keeps us trapped.

This creates a behavior that is no longer driven by content, but by the system itself. Not from real joy. But from the feeling that somewhere out there something is still waiting that is worth it. And if it doesn’t come, the system is set up so that we disappoint ourselves – but still can’t stop.

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References

1. Douma, E. H., & de Kloet, E. R. (2020). Stress-induced plasticity and functioning of ventral tegmental dopamine neurons. Neuroscience and Biobehavioral Reviews, 108, 48–77. https://doi.org/10.1016/j.neubiorev.2019.10.015

2. Michaelsen, M. M., & Esch, T. (2021). Motivation and reward mechanisms in health behavior change processes. Brain Research, 1757, 147309. https://doi.org/10.1016/j.brainres.2021.147309

3. Ihssen, N., & Wadsley, M. (2021). A reward and incentive-sensitization perspective on compulsive use of social networking sites: Wanting but not liking predicts checking frequency and problematic use behavior. Addictive Behaviors, 116, 106808. https://doi.org/10.1016/j.addbeh.2020.106808

4. Wang, J., & Wang, S. (2025). The emotional reinforcement mechanism of and phased intervention strategies for social media addiction. Behavioral Sciences, 15(5), 665. https://doi.org/10.3390/bs15050665

5. Fraser, K. M., Pribut, H. J., Janak, P. H., & Keiflin, R. (2022). From prediction to action: Dissociable roles of ventral tegmental area and substantia nigra dopamine neurons in instrumental reinforcement. bioRxiv. https://doi.org/10.1101/2022.08.15.501890

6. Milbocker, K. A., Smith, I. F., & Klintsova, A. Y. (2024). Maintaining a dynamic brain: A review of empirical findings describing the roles of exercise, learning, and environmental enrichment in neuroplasticity from 2017–2023. Brain Plasticity, 9(1–2), 75–95. https://doi.org/10.3233/BPL-230151

7. Dresp-Langley, B. (2023). From reward to anhedonia: Dopamine function in the global mental health context. Biomedicines, 11(9), 2469. https://doi.org/10.3390/biomedicines11092469