Some people are capable of seeing the sound and hearing the color. In science, this perception of music in the form of regularly and spontaneously manifested color patches, stripes, waves is called sound-to-color synaesthesia (chromesthesia).
Synaesthesia is an individual neurocognitive strategy: a special method of cognition, which manifests itself, when an unusually close connection of thought process and feelings (cognitive and sensory projection) is present.