Why Behavioral Psychology Makes Apps So Addictive

Variable Rewards Drive Behavior Change

In the 1950's B.F. Skinner researched rewards—when to give them and how often to give them. In Skinner's classic studies, rats were given a pellet of food (the reward) after they pressed a lever. Through this process, he was able to train the rats to press the lever on their own, and eventually to desire to press the lever. By varying this process, he and other researchers identified the effects of using different reward "schedules". For example, should you reward someone every time they do the behavior you are looking for? Or just some of the time? Learning schedules are frequently used to motivate user behavior in digital products.

Believe it or not, the most powerful schedule of reinforcement follows a variable schedule of rewards. Skinner observed that lab mice responded most voraciously to random rewards. The mice would press a lever and sometimes they’d get a small treat, other times a large treat, and other times nothing at all. Unlike the mice that received the same treat every time, the mice that received variable rewards seemed to press the lever compulsively. Moreover, the rats who had once received the variable rewards continued to press the lever the longest after the rewards stopped.

Believe it or not, giving users exactly what they want will make them less engaged over time.

Bizarrely, having a less predictable outcome - Will I get what I'm hoping for? - is actually more enjoyable. This is because our brains are wired to search endlessly for the next reward, never satisfied. Recent neuroscience has revealed that our dopamine system works to keep us searching through desire. The hunt itself is rewarding, and it explains why so many of our favorite mobile apps and social networks are so addictive.

Variable Rewards Are Embedded In Your Favorite Technology

Once you pay attention, you'll see that variable rewards are embedded in products all around you. Let's take a look at some you might recognize.

Email is a Variable Reward

Isn't email the worst? This never-ending do-to list can be a major time drain. Nonetheless, many of us find ourselves compulsively checking email throughout the day, sometimes without even noticing. Waiting in line, during commercials, or sitting at a stoplight? Your email somehow ended up open, didn't it? 

What gives? Email itself is very much a variable reward: sometimes it will have something wonderful in it ("A friend just RSVPed for your party!") while other times it will contain the mundane ("Your latest electric bill is here") or undesirable ("Account overdraft fee charged.") This uncertainty itself is a bit thrilling. There's that momentary pause while your email loads when you anticipate what you will discover. 

Video Games Naturally Leverage Variable Rewards

If you think email is addictive, what about mobile games that utilize variable rewards. Consider Candy Crush. The mobile mega-force, which involves matching sweets, is essentially a game of luck. Your success is dependent on which colors you have randomly been given, not your ability. This means that we lose more often than we win and we never know when the next triumph will come. Rather than discouraging us from playing, this actually makes the game even more enticing than if won easily. You can never predict when you’re going to win, but you win just often enough to keep you coming back for more.  

Facebook's News Feed Uses Variable Rewards

Similarly, your Facebook News Feed is full of variable rewards. Some of the content is interesting, and some of it isn't. Pictures of your best friend at a new winery? Awesome. Pictures of your distant cousin's garage sale? Less so. Because the good and the bad are mixed together, you have to continue scrolling to find the next "hit" of interesting information. This is incredibly important for a product like Facebook, whose goal is to keep users on their product as long as possible (in order to view more ads).

As you can see, variable rewards are all around us, and they are especially prevalent in some of our favorite products. 

Next up, when should you add variable rewards to your product? And how do you do it? See some the top tips from the team at PhD Insights.