When we experience something with several senses at the same time the memory formed after this experience will be stronger. For example, if one day, I speak to someone for the first time while listening to a song, I may remember him or her the next time I listen to this same song. Our brain associate senses and memories, actually, the senses are our sensors, the front door of any experience that will lead to a memory. Our senses are capable to revive emotions, places and moments with high intensity.
The smell is directly linked with the limbic system, which is a zone of our brain where emotions and memory are managed. When a familiar smell is perceived, it can reactivate extremely precise memories, often linked to childhood.
The different sound we can hear, and particularly the music can stimulate a huge brain network, including the medial prefrontal cortex, which is a brain zone involved into identity and emotions. That's why, when we listen to a song we listened in childhood, we can more easily remember the context : the people we were with, what we were feeling... And with some old people, even if they're suffuring from memory disorders a music can revive forgotten memories.
