Synesthesia (also spelled synæsthesia or synaesthesia, plural synesthesiae or synaesthesiae)—from the Ancient Greek σύν (syn), “together,” and αἴσθησις (aisthēsis), “sensation“—is a neurologically-based condition in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway. People who report such experiences are known as synesthetes.

Thanks wikipedia.

This used to affect me a lot when I was younger.  Whenever I thought of numbers, they would have very specific colors.  3 was brown, red was 5.  I still think this crossing of senses plays some sort of part in the way I learn and see things.  It apparently takes many different forms.  For example you might associate chicken with a pointy object, or you see the alphabet in colors or different sounds evoke different colors or objects.  maybe you associate monday with blue or a certain emotion.  maybe september has some sort of spatial identity in your memory.  I also realized a lot of people don’t even realize that they have synesthesia in some form.  Do you?