I was reading about an interesting phenomenon called synesthesia, in which “stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway.” This cross-over of senses often allows individuals to see letters, numbers, even days of the week in color; regardless of the color the letter is written in, individuals with this ability see a distinct color – “L” may be blue, “M” may be red. Some people with synesthesia also “hear” colors – sounds or music have a distinct color.
When I listen to music, it often evokes an emotion or feeling in me but definitely not colors. The emotion is usually tied to a past experience the music or song reminds me of. Research has shown that synesthesia is not the result of memories. There are several tests on a web site from the U.K., BBC - Science & Nature - Human Body and Mind, that one can take to determine if they have this blending of the senses. I definitely do not have it; I scored poorly on every one of them.
This entire web site is interesting and fun. It examines functions of the mind, personality, etc. in short surveys and psychology tests. And, the best part is that it actually gives you the results.