One can deliberately modify one's experienced reality by studying and changing the generators in one's mind that construct sensory experience, such as learning to 'unsee' one's face in a mirror by shifting from perceiving it as a face to perceiving the underlying geometry, then reassembling it differently; most people don't do this frequently because the outer mind (intuition and gut feeling) is usually smarter than rational thinking and prevents such reality-hacking because it's protecting something important you don't consciously understand.