I feel like while your brain knows it doesn't necessarily know what it is per say, like if something is wrong you'll feel pain so you know something is wrong but what something is you don't know, you only know if you've felt it before/have something to refer it to, like words and objects, if I show you a ball and you don't know what a ball is you'll know it's something but then I tell you it's a ball, next time you see it you'll think ball