text: Applies to other senses as well. If you stare at a picture for long enough it also tends to lose it's meaning. Everything only has meaning when it is put into context with something else, how it interacts with other objects. Take an object out of it's normal context, isolate it and it loses something. Take that same object and place it with objects that it would normally never be seen with and it takes on a whole new meaning, this was the idea of the art movement of Surrealism and a mechanism for exploring the technique of lateral thinking. When a word is repeated over and over it loses it's meaning because the brain kind of 'loses interest' in it's normal activity of associating the word with other words and meanings leaving it with nothing but the literal input of the sound of the word itself.