One of the key visual (and musical) elements of 2001's A Beautiful Mind was the mental epiphanies of the lead character, mathematician John Nash (Played by Russell Crowe). During filming, director Ron Howard decided that Nash's delusions should always be introduced first audibly and then visually. This provides a clue for the audience and establishes the delusions from Nash's point of view. However, the historic John Nash had only auditory delusions with the visual delusions used to help the audience see what Nash was thinking or focusing on. The filmmakers developed a technique to represent Nash's mental epiphanies based on real mathematicians descriptions of such moments as a sense of "the smoke clearing", "flashes of light", and "everything coming together". It was based on this description that the filmmakers used a flash of light appearing over an object or person to signify Nash's creativity at work.
In addition, the film's composer, James Horner (a frequent collaborator of Howard and producer Brian Grazer) contributed to this aspect of the character. In fact, a running discussion between the director and the composer was the concept of high-level mathematics being less about numbers and solutions, and more akin to a kaleidoscope, in that the ideas evolve and change. After the first screening of the film, Horner told Howard: "I see changes occurring like fast-moving weather systems". He chose this as another theme to connect to Nash's ever-changing character. Horner also chose Welsh singer Charlotte Church to sing the soprano vocals after deciding that he needed a balance between a child and adult singing voice as he wanted a "purity, clarity and brightness of an instrument" but also a vibrato to maintain the humanity of the voice. The result was a multilayered portrayal of Nash's mental state. Stay tuned!