Critics often criticize Facebook regarding privacy concerns. Most recently, the social network is working on combating fake news, fake accounts, and managing revenge porn. Not to mention the fact that Russia spent thousands of dollars in advertisements to manipulate Americans before the election. Mark Zuckerberg has been working on fixing all of that, but he may not have expected to receive criticism by Facebook Ex-President Sean Parker at an Axios event.

Sean Parker told the audience that he would not be surprised if Zuckerberg blocked him from Facebook after the interview. He delivered a fascinating look at how the company was designed with a single mission in mind. “How do we consume as much of your time and conscious attention as possible?”

It was from that point on; Facebook created a system of “likes,” which was base don giving users “a little dopamine hit” in the form of positive reinforcement. Parker worries about how the resulting social media platform changed the culture and human psychology.

“The unintended consequences of a network when it grows to a billion or 2 billion people and … it literally changes your relationship with society, with each other … It probably interferes with productivity in weird ways. God only knows what it’s doing to our children’s brains … It’s a social-validation feedback loop … exactly the kind of thing that a hacker like myself would come up with, because you’re exploiting a vulnerability in human psychology.”

The positive reinforcements, in turn, motivate people to post more often, which generates more page views for Facebook and, therefore, more ad revenue for the company. Research has shown this to be true. A May 2016 study by UCLA researchers discovered that a teen’s brain reward regions become excited when teenagers see high numbers of “likes” on their photos.

While the study did not suggest social networks were as addictive as heroin, researchers did note that a large number of “likes” had a larger effect on the teens than just a few. So much so that social media can impact behavior. Researchers in the UCLA study, Lauren Graham explained, “If your teen’s friends are displaying positive behavior, then it’s fabulous that your teen will see that behavior and be influenced by it.”

Following the success of Facebook, other developers have gone on to use this idea of narcissistic tendencies to make money. For example, the rise of Instagram, Snapchat, and other platforms are additional ways for users to distract themselves from reality. Parker admits that he and Zuckerberg “understood this consciously” – suggesting they realized they were taking advantage of a person’s need for approval from others, “and we did it anyway.”