it's amazing how the brain associates sounds with memory. i can listen to a song for the first time in three years, and it will bring back memories of the first time i heard it, or a summer when i listened to it often. it can often trigger the olfaction cells to bring back memories of certain smells too.
i get a deep-rooted aversion to whatever ring tone i use for an alarm on my phone. it was over three summers ago, but i still shudder involuntarily if i hear a particular Nokia ring tone; it was the music that so rudely jarred me awake at a quarter to seven to go rouse a bunch of cranky teenagers to set the tables in the camp dining room.