The Science of Social Media

Social media is one of the defining technologies of the 21st century, but what’s really going on behind the scenes?

Does social media make us more friends?

On average, people have five social media accounts and spend an hour and a half checking them every day. It’s billed as a way to make and strengthen connections with people, but, for all the social benefits, there is an argument that all of the time we spend online is taking away from the relationships that we make in the real world. According to evolutionary anthropologist Robin Dunbar, we can only maintain up to 150 friendships at a time. This is known as the Dunbar Number, and it’s based on the social groups that we evolved to live in; it’s the size of most villages recorded in the Domesday Book, for example. Beyond that number, we can’t maintain meaningful relationships because we don’t have enough brain processing power or enough time to work on maintaining the connections. Dunbar looked into social media friends in 2016 and found that, even though it feels like we have lots of friends online, these sites don’t actually help us to be more connected. People had around the same number of close friendships online and offline.

How do Snapchat filters work?

Selfie filters are based on the Viola Jones algorithm, which finds faces by scanning images for areas of light and dark, but Snapchat’s Active Shape Model can see in even more detail. The developers created a map of the average locations of key facial landmarks – like the edges of the eyes and lips – by manually marking their positions on dozens of photographs of real people. The points were then joined up to create a 3D model of a head. In the Snapchat app, the average map is laid over your face and compared to your pixel data so that the points can be tweaked to fi t your exact features. With your custom model completed, your face can then be textured and deformed.

Does social media affect our health?

Social media might seem light-hearted, but it has a darker side. In 2016, Childline delivered 12,000 counselling sessions related to online issues and cyberbullying, and a study of over 1,700 young adults by the University of Pittsburgh found that the more time people spend on social media, the more likely they are to be depressed. In a UK survey of nearly 1,500 teenagers and young adults, researchers found that image-focused sites like Instagram and Snapchat performed the worst when it came to anxiety and mental wellbeing. This doesn’t necessarily mean that social media causes mental health problems – it could be that people spend more time on the sites when they are feeling down or anxious. On the other hand, social platforms can also be used to raise awareness of mental health and to help people find somebody they can talk to.

Is social media addictive?

For some, social media becomes more than just a way to connect with friends; checking their feeds can turn into a compulsion and they become unable to control the amount of time spent on the internet. Internet addiction disorder, also known as problematic internet use or compulsive internet use, is unique to the 21st century, but it runs on biological impulses that have been around for millennia. Our brains are wired to seek reward – it’s what encouraged our ancestors to look for high-calorie sweet and fatty food, or to form lasting relationships with others – and it also drives addiction. The reward comes in the form of a chemical signal called dopamine, which is released in a part of the brain called the nucleus accumbens. Dopamine makes us feel good and drives us to repeat positive behaviours. However, some people can develop a tolerance to the dopamine rush, needing more and more to produce the same effect.

How does a meme go viral?

The word ‘meme’ was invented by scientist Richard Dawkins in 1976 to explain how ideas spread from person to person, replicating and mutating like genes. There isn’t a formula for success, but researchers at the University of Memphis found that shorter memes, memes with swearing, and memes that could be reproduced quickly using a template were the most likely to do well.

How does WhatsApp's end-to-end encryption work?

Since 2016, every message you send using WhatsApp has been end-to-end encrypted: this means that it can only be read by you and the recipient. It’s based on something called the Signal Protocol. When you start a chat it opens an encrypted session. This then calculates something called a ‘master secret’ using keys that are unique to you and the person you are sending messages to. The master secret is used to create a root key and a chain key, which in turn is used to make unique message keys for every message you send. When you hit the send button the message is scrambled and locked with the key. When it reaches your friend’s phone, they use their own private keys and the keys from the header of the message to unscramble it again.

How secure is the cloud?

It’s easy to imagine that our data is secured somewhere up in the air, far out of the reach of prying eyes, but ‘the Cloud’ is actually a euphemism for giant server farms that hold your documents and images on their physical hard drives. When you upload your data to the Cloud, it’s saved to these computers ready for you to download again when you need it next. The first part of Cloud security is down to the provider; they need to make sure that their infrastructure is secure both digitally and physically. To do this they encrypt critical data, employ security personnel to protect their servers, and develop digital security systems that deter, detect and counter any attempts to access private files. The second, and more vulnerable part of security is down to you. If people want your data they’ll go for it through the easiest route, and this isn’t usually by taking on the tech giants; it’s much simpler to gain access to your passwords. The easiest way to secure your data is to make your codes stronger, change them often and guard yourself against phishing scams. It never hurts to make a backup of your files, too.


 This article was originally published in How It Works issue 102, written by Laura Mears


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