In his book Brain Rules John Medina says:
Visuals have x10 the impact on people as words, they are more memorable and emotional. It just so happens that memory and emotion are the two things that drive decisions.
We have talked before about the importance of sketching. We have shared how we employ sketching on client projects as well as when designing our own tools. Yet we still see folks using the painful requirement specs to communicate their ideas. We are huge fans of Dan Roam and the work he's done bringing attention to visual thinking and problem solving. Below is a great video of an explanation he gave illustrating the power of visual problem solving:
Instead of writing down requirements, visualize the problem you're trying to solve. Once you visualize it you can motivate other people by visualizing it for them too!