One of the artists, Annie Cavanagh, describes her approach to making art with scientific images. For example, the one above started as a black and white electron micrograph and has been "falsely colored." That's the term for it, not an accusation. In some cases the color is added to make the image true-to-life, but in others, the color is more illustrative or purely decorative. I'm not sure orange/yellow/green neon is where I would have gone with caffeine.
What color is a caffeine buzz? Purple maybe?