Neuroscientist Shannon Odell is back, and this time she’s inside your freaking computer. Based on the three main platforms — Facebook, Instagram, and Twitter — Odell analyzed all the way social media is affecting our brains. (Sorry, Google+, there just wasn’t enough data.)

You know Facebook; it’s the website from that Jesse Eisenberg movie. As it turns out, a lot of people use it. There are currently 2.2 billion users on Facebook, which is roughly seven times the population of the United States. It’s how most people find out their enemies from high school are pregnant.

The real reason most people love Facebook, however, is the coveted “like” feature. The like is thought to be directly connected with the social reward pathway in the brain. This isn’t a coincidence. Facebook researchers have figured out the perfect color, placement, and size of the like button to maximize the impact on your brain. If this sounds a little … manipulative, well, it is. But that doesn’t necessarily mean you need to delete your Facebook account. While users do show activation of the amygdala and the striatum when they’re using Facebook — two areas of the brain associated with addiction — there wasn’t enough significant activation in lower prefrontal areas of the brain, which are often associated with substance addictions. So you can rest easy knowing your Facebook usage is not as bad as your cocaine addiction.

Instagram, meanwhile, is the classy version of Snapchat your mom just discovered. The neuroscience behind posting pictures on Instagram is often associated with feelings of loneliness. Introverts, interestingly enough, are more likely to post, whereas extroverts like and comment on their posts.

But when it comes to scrolling, it all comes back to the like. Functional MRI studies of teenage brains show increased activation in the visual cortex of the brain when viewing a photo with a significant amount of likes versus the same photo with only a few likes. This suggests that our brains intuitively pay more attention to something that has been arbitrarily rated better socially, regardless of the content. When viewing their own content, there was increased activation in the reward pathways of the brain when their photos were accompanied with more likes. In other words, it just feels good to know your brunch pic is resonating with your friends.

Twitter is the modern-day equivalent of a young paperboy yelling newspaper headlines from a street corner. Getting your news from the internet is totally fine, but failing to filter out fake news is not. One study found, however, that users were less likely to be swayed by false information when it was presented in a Twitter-like format. If your Twitter intentions are more focused on crafting the perfect retweetable content, then you’ll want to work out your temporoparietal junction. The TPJ is associated with mentalizing, or understanding how others think and feel. There is a significant increase in activation of the TPJ when dealing with the concept of viral or successful ideas. So, the science of the retweet boils down to empathizing with your fellow comrades, not from reading a dozen think pieces.

Social media isn’t going anywhere, and neither are our brains. So, do yourself a favor, and have Shannon Odell explain their relationships to you.