After sex, oxytocin — often referred to as the “cuddle hormone” — is released, especially in cis women and those assigned females at birth (AFAB). "Oxytocin gives us that warm and fuzzy feeling after orgasms that make many of us want to nap, snuggle, or get comfy," says Francis. "If open to connection, this hormone makes us feel connected or attached to the person we have just slept with."

Oxytocin also has pain-relieving properties that can help alleviate symptoms we may have been experiencing before or during sex, such as stress, headaches, or discomfort from rougher play.

The cerebellum is the area in the back and bottom of your brain that’s connecting to movement, coordination, and motor skills. In addition to physical movement, Francis shares, the cerebellum is involved in more complicated analyses of the world, like balance and even emotional processing.

"Activation in your cerebellum occurs throughout the sex to increase muscle tension, which is related to sexual stimulation,” says Francis. “This tension can create a pathway for orgasm."

Because so many of your muscles are used during sex, having sex activates the cerebellum. Francis adds there are many theories suggesting that after sleeping with someone, the activation in your cerebellum is involved in how you process your feelings about them. In other words, if you ever hooked up with someone and then realized you liked them more (or less) than you thought, it may be connected to your cerebellum.

If you ever had D.A.R.E. in grade school, you probably learned about getting high on life. Cheesy infographics aside, the neurotransmitter dopamine is known for making you feel happy. Not only is it released during pleasurable sex, but dopamine floods your brain during orgasm, too. That’s why the big “O” feels oh so good.

"Dopamine gives us the feeling of euphoric reward — it makes us feel like we have achieved something wonderful, like winning the lottery," says Francis. "Dopamine is one of the brain chemicals involved in addiction — it tells us, 'That was good, we liked that, we should do that again and feel good again.'“

Whether you’re getting it on with someone new or making love with your long-time partner, having sex fills your brain with dopamine, making you want to chase the feeling you’re getting.

Francis says that having sex doesn’t just activate the cerebellum, it engages your hippocampus, a part of the brain that’s associated with memory. Whether sex feels like a blur or you can recall every detail, the hippocampus is likely to blame. "Depending on the context, the hippocampus’ involvement in sex can either enhance or worsen your memory," says Francis.

While you may instantly forget individual sexual encounters, over time, having more frequent sex (and therefore more frequent engagement of the hippocampus) has been linked to an increase in memory. According to a 2018 study from the University of Wollongong in Australia of 6,000 adults, participants who got had sex more often displayed stronger short-term memory.

Have you ever had a toe-curling, screaming orgasm where you felt out of control — but in a good way? Francis shares that’s likely because having orgasms shuts down part of the orbitofrontal cortex of the brain, a region responsible for decision-making. Whether you moaned louder than you planned or your pelvis moved in a new way, Francis notes that during an orgasm, you may not really know what your body is doing.

"Although just for a moment, a pause in function of the lateral orbitofrontal cortex creates that out-of-body sensation sometimes experienced during orgasm," says Francis. "This may look like a spasm, a tic, a limpness, or just a sense of being overcome by your orgasm."

The orbitofrontal cortex shutting down also makes you feel fewer inhibitions, meaning you may feel bolder and daring between the sheets. This means you may feel less concerned about what you look or sound like in a given sexual scenario, and are more focused on what feels good for you.

Have you ever hooked up with someone you weren’t super into but then somehow, inexplicably, felt possessive over them? One of the hormones released after sex is vasopressin, which helps you regulate thirst, but is also involved in the development of attachment. How’s that for thirst trapping? Vasopressin, which is made in the hypothalamus, is released from the pituitary gland in the brain after sex.

"Increased vasopressin is correlated with devotion to and protection of the person you slept with and is believed to be the hormone that motivates us to be monogamous," clinical psychologist Jennifer Sweeton, Psy.D., M.S., M.A. tells Bustle. "Research has shown that individuals who report cheating in their romantic relationships tend to have a gene variation that keeps their vasopressin production low."

When you’re super into someone you may be inclined to look past some of their red flags or cringe-worthy habits. Suddenly their loud chewing doesn't sound so loud or their “screenplay” sounds really interesting. There's a reason you have a hard time producing a logical, analytical assessment of the people you slept with: the neural pathway involved in social judgment turns off during sex.

"This is likely why we have the saying that 'Love is blind," says Sweeton.

As Sweeton describes, when your social judgments are down, your focus may shift from thoughts to emotions. You may think about how your crush makes you feel more than how they dress or what job they have. Because of this, you may care less about external ideas for your relationship and just center on what’s in your heart.