You've probably experienced this: you come home to a plate of freshly baked cookies in the kitchen, and when the scent of chocolatey goodness hits your nose you're instantaneously transported back to your grandmother's house.
The phenomenon is called odor-evoked biographical memory, but how exactly does it allow for specific scents to magically bring back a memory?
"There's a big difference between the way your body handles sight, sound, taste and touch and the way it processes smells," Hank Green, host of the YouTube series SciShow, says in a new episode (above).
Unlike other senses, when a smell is processed in the brain, it travels directly to the amygdala and the hippocampus -- regions that both deal with emotion and memory respectively. This allows for the scent to be stored in your brain as a memory along with a certain experience or emotion.
Now, go call your grandma and reminisce!