Likes and comments on photos and posts were meant to give us little dopamine hits to keep up coming back, Parker said. 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".
Parker admitted that when he was helping advise Facebook as it grew, he was unsure if he understood the consequences of what could happen when the network grew to the 2 billion people who are on its platform now.
"God only knows what it's doing to our children's brains", Parker said.
Parker left his post as president of Facebook in 2006 after less than two years but remains chairman of a Facebook segment dedicated to awareness and social causes, according to his LinkedIn account.
Facebook's first president Sean Parker leveled criticism at the social network he once headed, saying how the network was created to be addictive and is concerned about its effect on children. Top lawyers from Facebook, Twitter and Google testified last week before several congressional committees that probed the firms on how Russian actors used their platforms to interfere in the 2016 presidential election.
Facebook didn't respond to a request for comment on Parker's remarks. "And that's going to get you to contribute more content, and that's going to get you ... more likes and comments".
He added that he, as well as Mark Zuckerberg, Facebook CEO, were well aware of the results that would be produced as a result of the constant social validation.
Sean Parker also explained their thought process as they went about building Facebook and how other social networks are built.
Parker, 38, is now the founder and chair of the Parker Institute for Cancer Immunotherapy.
Parker isn't the only ex-Facebooker to raise concerns about the addictive nature of the social network and about tech's psychological and societal effects.