system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do kids fall out of the bed/why don't we fall out of the bed?
gpt
I would say that it's because their proprioceptive senses are underdeveloped. This is the sensory capacity that allows us to perceive the movement and positioning of body parts related to other parts and external objects (such as a bed). The reason adults don't (usually) fall out of bed is because we have more solid mental maps of our bodies and the space they require as well as the average bed and the space it allows.