Chapter 11: Exploiting addiction

Consider some of the following criteria against your own behaviour, and your friends and family:

  1. Using something for longer than you intended.
  2. Trying to cut down, but not quite managing it.
  3. Usage requires you to spend a lot of time recovering (from sleep deprivation, for instance).
  4. Feeling cravings when you’re not using it.
  5. Usage causing you to fail to fulfil your obligations (at work, school or home, and so on).
  6. Continuing to use it even though it interferes with your relationships (for example, recurring arguments with or resentment towards your partner).
  7. Using it in hazardous situations (such as while driving).
  8. Choosing not to attend social or recreational events so you can use it instead.
  9. Feeling withdrawal symptoms when you can’t use it.

This list is paraphrased from the DSM-5, the book used by US psychiatrists to diagnose mental health disorders – in this case, substance abuse disorder.1 But it’s easy to look at this list and think about compulsive behaviours in games and other digital products. It must look familiar if you know someone who has developed an unhealthy habit with League of Legends, Call of Duty, Twitter, Facebook or whatever else. This is known as behavioural addiction – where there are no drugs involved – but the phenomena are very similar.2

In fact, some neuroscientists claim they have found evidence that all addictions share the same biological origins in the human brain.3 Whether you’re abusing a drug or just can’t stop playing League of Legends, they argue that it’s the brain’s reward system that’s being tapped into – specifically, the mesolimbic dopamine pathway.4

It’s easy to exploit addiction for profit if you’re willing to overlook the negative impacts. Some products are designed from the ground up to be as addictive as possible, and they use various forms of manipulation and deception to do this. To quote the first president of Facebook, Sean Parker:5

How do we consume as much of your time and conscious attention as possible? […] we needed to sort of give you a little dopamine hit every once in a while because someone liked or commented on a photo or a post or whatever… It’s a social validation feedback loop… You’re exploiting a vulnerability in human psychology… [The inventors] understood this, consciously, and we did it anyway.
— Sean Parker, 2017

Surprisingly, one of the most effective ways to make something addictive is to design it so that recipients don’t always get what they want, and to only let them get it in an unpredictable way. This is called a ‘variable reward schedule’ or ‘intermittent reinforcement schedule’.

This was famously demonstrated by psychologist BF Skinner in 1938.6 He conducted experiments with rats and pigeons in which he presented them with a lever to press. When the animal pressed the lever, they received a food pellet or some other reward. Skinner discovered that when the reward was given on a variable schedule (that is, in an unpredictable way), the animals were more likely to keep pressing the lever than when the reward was given on a fixed schedule (in a predictable way). This is best understood in the context of the dopamine cycle, shown below.7

Five words joined by arrows in a cyclic form: ‘Seek’ leads to ‘Anticipate’ and from there to ‘Trigger’, ‘Reward’ and ‘Want’, which points back to ‘Seek’.
Simplified diagram of the dopamine cycle

It’s believed that the variable schedule works because the animals never know when the next reward is coming. This creates a sense of excitement and anticipation that keeps them engaged in the behaviour for longer periods of time, which is now understood to relate to the dopamine cycle (shown above). A predictable schedule breaks the cycle because...

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Since 2010, Harry Brignull has dedicated his career to understanding and exposing the techniques that are employed to exploit users online, known as “deceptive patterns” or “dark patterns”. He is credited with coining a number of the terms that are now popularly used in this research area, and is the founder of the website He has worked as an expert witness on a number of cases, including Nichols v. Noom Inc. ($56 million settlement), and FTC v. Publishers Clearing House LLC ($18.5 million settlement). Harry is also an accomplished user experience practitioner, having worked for organisations that include Smart Pension, Spotify, Pearson, HMRC, and the Telegraph newspaper.