Another funny thing happens in the brain at that moment. The brain remembers the smell in a picture of the past. Smells cause memories to return. Some people respond emotionally to smells because of the thoughts that come to their minds with a smell. They smell a pine tree; they think of Christmas. They smell apples cooking and remember a particular party or a childhood memory of apple pies. They smell peanut butter and remember being in school and eating peanut butter sandwiches for lunch. In other words, smells cause many reactions. The brain's smell memory connection is an interesting phenomenon.