What happens to your brain when you scroll on social media

Ever wondered what’s happening inside your brain when you get stuck scrolling through social media feeds? You may be aware of the thoughts and feelings that are popping up, but what about the way your brain is actually changing shape as you flick your finger down that screen?

A respected neuroscientist* has explained the ways that doom scrolling is reshaping our brains – and how it could be affecting the health and development of younger people in a major way.

Associate Professor Susannah Tye, research group leader at the Queensland Brain Institute, said using social media directly affects the chemistry of the brain, reinforcing addictive behaviour and making it difficult for important skills like critical thinking and sustained focus to develop.

Our brains don’t finish developing until we are well into our 20s. The prefrontal cortex*, which is the part of our brain responsible for things such as reasoning, impulse control and long-term planning, doesn’t finish maturing until at least the age of 25 – maybe even later for some people.

“I think there’s a lot of potential for damage to be done during formative* years, and we haven’t even begun to understand how that’s affecting vulnerable kids, including neurodivergent* kids who may be at greater risk for adverse* outcomes,” Assoc Prof Tye said.

THE BRAIN CHEMISTRY OF SOCIAL MEDIA
Assoc Prof Tye said that when someone went on TikTok or Instagram and started scrolling they got a dopamine hit straightaway.

Dopamine is a neurotransmitter* released by the brain when something is important and enjoyable. It’s key in the way we form habits and is central to the brain’s reward system. When our brain releases dopamine during moments of pleasure – it’s the brain’s way of saying, "you should do this again and again."

“The way our brains are wired is whenever something jumps out at you, the neurotransmitter dopamine will be released, and that signals to your brain that this is important, and it helps you pay attention and respond to it,” she said.

“But we also get dopamine when things are pleasurable, so drugs of abuse stimulate a massive amount of dopamine which is released into the brain and this artificially hijacks attention and motivation systems, which can lead to addiction.”

She said social media was a “mix” of the two.

“It’s capturing our attention with a lot of moving pictures and bright lights and sounds,” she said.

“And then it is designed to be rewarding and reinforcing, so it’s training the brain to keep repeating that through a cycle of habit formation.

“It’s sort of triggering all the release of those chemicals that reinforce habits.”

Medical director at Stanford University Anna Lembke has likened smartphones to drugs. She compared them to a modern-day hypodermic needle that delivers a big dose of digital dopamine 24/7.

WHY DO WE GET ADDICTED TO BAD NEWS?
But why do we doom scroll when the experience is often negative and brings on anxiety?

Assoc Prof Tye said that although most of us associate dopamine with pleasure, the more accurate way of looking at it was as a neurotransmitter that signals importance.

“We often think of dopamine as the reward neurotransmitter, released when drugs of abuse or high sugary foods give you a high … but what most people don’t understand is that stress or negative events also stimulate dopamine in just the same way,” she said.

”It’s actually released when something is important, irrespective of being good or bad – the neuroscience term for that is ‘salient*’.”

She said young people were particularly vulnerable and the long-term consequences of social media use on their developing brains was unknown.

Assoc Prof Tye said that with everything we understand about the dopamine system, it was likely that doom scrolling was quietly reshaping the brain and making our brain health worse over time by keeping us in a constant fight or flight* mode.

When we are in this fight or flight mode, or “survival brain”, the stress hormones adrenaline* and cortisol* are constantly being released in response to a perceived danger, which can lead to anxiety, depression and other health problems.

But it gets worse. The more you do something, the better the brain gets at it, making it harder to break out of the cycle of stress and anxiety. This becomes even more dangerous for young people who haven’t developed that part of the brain that deals with complex problem solving.

“When people, especially young people, spend large amounts of time in fast, emotionally reactive loops online, they’re repeatedly strengthening the limbic*, ‘survival brain’ circuits involved in rapid, impulsive responses,” Assoc Prof Tye said.

“Because of neural plasticity* (the brain’s ability to adapt), the networks we use most become stronger, and the ones we neglect weaken.

“If our daily habits keep reinforcing reactive*, emotionally charged patterns of attention, we’re giving far less energy to the higher-order* cognitive networks that support critical thinking, complex problem-solving, sustained focus, and adaptive* decision-making.

She said this meant we were “losing the opportunity to develop and strengthen the neural* systems that protect and serve us” because they help us “think clearly and navigate complexity”.

“These skills are exactly what we need to navigate an increasingly complex and rapidly changing world,” she said.

She said more research was needed in this area but there were already many red flags.

POLL

GLOSSARY

• neuroscientist: a scientist who studies the brain and the nervous system as a whole
• prefrontal cortex: the region at the front of the brain’s frontal lobe that is responsible for decision making, planning, complex thought and personality. It brings together information from all parts of the brain to manage complex behavioural, emotional and thought processes
• formative: the years when you are still growing, learning and developing
• neurodivergent: having a brain that works differently to what is considered typical in society, often used in reference to people who are autistic, ADHD or dyslexic to name just a few
• adverse: worse or more difficult
• neurotransmitter: chemical messengers released by the nervous system that carry chemical signals between nerve cells
• salient: when something stands out in a very noticeable way
• fight or flight: an instinctive response to threat that gets you ready to either run away or fight for your life. When the body is faced with threat, the nervous system releases different chemicals and goes through different physical responses to get it ready for action. But if the threat isn’t a physical one and is from repeated stress or being bombarded with bad news all the time, you might get stuck in fight or flight and not be able to rest and digest, which is the nervous system state you need to be in to recover from all those stress hormones flooding through you. Mindfulness meditation, exercise and switching off from devices each day can help break the fight or flight cycle. Talking with an adult you feel comfortable with, like a parent or school counsellor, can also help
• adrenaline: a hormone that makes your heart beat faster and sends more blood to your muscles so you can react quickly to danger
• cortisol: a stress hormone that increases sugar in the blood to give you more energy when you are faced with danger and slows down your digestive system and other bodily processes so that you can direct all your energy into surviving
• limbic: the limbic system of the brain, responsible for the behavioural and emotional responses we need for survival
• neural plasticity: the brain’s ability to reorganise itself and form new neural pathways or strengthen its existing ones
• reactive: reacting to things without contemplation, as opposed to responding to things after careful thought and consideration
• higher-order: complex mental activities such as reasoning, problem solving and creativity
• adaptive: being able to change the way you think based on circumstances changing
• neural: relating to a nerve or the nervous system

EXTRA READING
Snap’s AI has teens in the dark
U16 social media ban explained
23,000 Aussie kids turn off socials

QUICK QUIZ
1. What is the prefrontal cortex responsible for?
2. When does it usually finish maturing?
3. Which neurotransmitter is released by the brain when you scroll on social media?
4. What does salient mean?
5. In what way does neural plasticity make it harder to break the habits of social media use and develop sound critical thinking skills?

LISTEN TO THIS STORY

CLASSROOM ACTIVITIES
1. Create a shock advertisement
Shock ads are ads that try to surprise or shock people so they stop doing something that could be bad for them — like smoking or speeding.

Your task is to create a shock ad that encourages kids your age to stop scrolling on social media. Your ad should:

• Be something kids would see while they’re scrolling
• Make them stop and think
• Encourage them to put their device down

You can present your ad by drawing a picture or storyboard; or creating a digital version (like a short video, image, or poster).

Time: allow 30 minutes to complete this activity
Curriculum Links: English; Digital Literacy

2. Extension
Choose a different target audience and produce a second shock advertisement. Think about how what shocks them about social media scrolling might be different to what shocks your original audience.

Time: allow 30 minutes to complete this activity
Curriculum Links: English; Digital Literacy

VCOP ACTIVITY
Vocabulary recycle
There is some vivid vocabulary being used in the article, and I am not just talking about the glossary words. Go through the article and highlight the high-level language that you are impressed by in yellow.

See if you can borrow two of these wow words to reuse in your own way.

Remember vocabulary is a great way to connect with the audience, but you need to think about who your audience is so you make great word choices.

Who will the audience be in your recycled sentences?