Children often say it best.
My child said this as he heard me speaking about ADHD.
I asked him what he meant, and he said it’s what a room seems like to him. I asked him what an empty room seems like, and he described how he will notice the shapes, curves, and corners of the walls; bumps on the ceiling; light seeping under the door; and the texture of the floor, adding that carpet’s like a maze of threads. He concluded, “Even an empty room is filled with so much. It’s insane.”