The most basic way to get someone’s attention is this: Break a pattern. Humans adapt incredibly quickly to consistent patterns. Consistent sensory stimulation makes us tune out: Think of the hum of an air conditioner, or traffic noise, or the smell of a candle, or the sight of a bookshelf. We may become consciously aware of these things only when something changes: The air conditioner shuts off. Your spouse rearranges the books.
