This document discusses subliminal messages and stimuli. It defines subliminal messages as messages that influence or affect someone on a subconscious level without being consciously aware of them. Subliminal stimuli are exterior factors that are strong enough to trigger neurons in the brain but not strong enough for the conscious mind to detect. Common types of subliminal messages discussed include audio tapes, back masking, silent messages, and visual images. The document also explores how brands now appeal to all 5 senses with "subliminal actions" and questions where to draw the line between transparency and subliminal brand communication.