Evoking memories.

It's funny how a certain smell, or sound, or place can evoke a memory in you. Today I went to a church that is not my regular church. I went there because I had been invited to go and talk about the work I do. During the service several of the songs sung were ones that could be found on a set of CD's that were played quite a lot when my mum and auntie were in hospital and the hospice. The memory of place and emotion that came flooding back to me were overwhelming and unexpected. I have sung those songs since, so why was it that in this strange church they evoked such a strong actually and emotional memory.