Close your eyes, take a deep breath \u2014 and imagine the aroma of warm apple cider, fresh baked pies, and a stuffed turkey roasting. If you\u2019re like most people, these fragrant holiday traditions will immediately take you back in time to happy celebrations spent with family and friends.\nThe holidays offer a rich source of smells that stir powerful memories of the past. In fact, the scents that waft from certain foods, plants, candles, and other items create an intimate link between our emotions and our past, says Rachel Herz, Ph.D., an expert in the psychological science of smell and the author of The Scent of Desire: Discovering Our Enigmatic Sense of Smell.\nWhy are scents so deeply connected to our emotions and nostalgia? It has a lot to do with the biology of our brain.\nOur sight, hearing, and other senses send signals to the \u201cthinking\u201d part of our brain for processing. But our sense of smell is directly linked to the deep part of the brain that stores memories and processes emotions. There, the brain forges a strong bond between scent and specific memories.\nHow It Works\n\nNeurons in your nose detect the odor and send signals to the brain.\nOlfactory bulbs in the brain decode the signals.\nThe olfactory bulb is part of the limbic system \u2014 an area so closely associated with memory that it\u2019s often referred to as the \u201cemotional brain.\u201d\n\n\nThe system includes the amygdala, which processes emotion, and the hippocampus, which is responsible for \u201cassociative learning\u201d.\n\nSimply put, we learn to associate a particular smell with a particular event \u2014 like the smell of baking holiday cookies at Grandma\u2019s house. The scent \u2014 as well as the memory and emotion it recalls \u2014 stick with us for life.\nFeelings evoked by holiday smells have special meaning to us because of the personal connection we have with them. Those aromas can instantly transport us down memory lane with multiple emotions and vivid mental images for the place or person we associate with the smells. Many of these memories trace back to our early childhood; in fact, some researchers believe our sense of smell and our reaction to them begin in the womb.\nSo this holiday season, raise a toast to the many heartwarming and unforgettable moments your sense of smell has inspired throughout your life. And here\u2019s to creating many more this holiday season!