The Anxious Generation: How the Great Rewiring of Childhood Is Causing an Epidemic of Mental Illness

by Jonathan Haidt

App designers often use a four-step process that creates a self-perpetuating loop, shown in Figure 5.3. Figure 5.3. The Hooked model. From Nir Eyal’s 2014 book, Hooked: How to Build Habit-Forming Products. In the book, Eyal warned about the ethical implications of misusing the model in a section titled “The Morality of Manipulation.”55 The Hooked model guides designers through the loop they need to create if they want to build strong habits in their users. The loop starts with an external trigger, such as a notification that someone commented on one of her posts. That’s step 1, the off-ramp inviting her to leave the path she was on. It appears on her phone and automatically triggers a desire to perform an action (step 2) that had previously been rewarded: touching the notification to bring up the Instagram app. The action then leads to a pleasurable event, but only sometimes, and this is step 3: a variable reward. Maybe she’ll find some expression of praise or friendship, maybe not. This is a key discovery of behaviorist psychology: It’s best not to reward a behavior every time the animal does what you want. If you reward an animal on a variable-ratio schedule (such as one time out of every 10 times, on average, but sometimes fewer, sometimes more), you create the strongest and most persistent behavior. When you put a rat into a cage where it has learned to get food by pressing a bar, it gets a surge of dopamine in anticipation of the reward. It runs to the bar and starts ...