Facebook's first president Sean Parker said Wednesday that the social media giant was designed to exploit "human vulnerability."

"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," Parker said at an Axios event in Philadelphia. "It's a social validation feedback loop. It's exactly the kind of thing that a hacker, like myself, would come up with because you're exploiting a vulnerability in human psychology." 

He went on to say the "[The inventors] understood this, consciously, and we did it anyway."

Parker says he now wonders about the consequences of Facebook on future generations. 

"God only knows what it's doing to our children's brains," he said. 

Mental health experts say it's having a negative impact. Andrew Malekoff, of the North Shore Child and Family Guidance Center, says those overly absorbed in the site often become isolated, anxious and disconnected. 

Malekoff says parents should consider putting limits on the time their children spend on social media.