Scent and Memory Among Older Adults
“And soon, mechanically, weary after a dull day with the prospect of a depressing morrow, I raised to my lips a spoonful of the tea in which I had soaked a morsel of the cake. No sooner had the warm liquid, and the crumbs with it, touched my palate than a shudder ran through my whole body, and I stopped, intent upon the extraordinary changes that were taking place. . . . I was conscious that it was connected with the taste of tea and cake, but that it infinitely transcended those savours, could not, indeed, be of the same nature as theirs. ”
The sense of smell has a unique connection to memory and emotion in the human brain. The olfactory pathway bypasses the the sensory processing structure in the thalamus through which all other sensory inputs flow. The olfactory cortex includes the amygdala, which is involved in emotion and emotional memory, as well as the hippocampus, which is involved in associative learning and memory. This means that the smelling activates emotionally-poignant memories very directly.
Nostalgia, the sentimental longing for one’s valued past, is a bitter-sweet experience that leads to improved affect, enhances self-esteem, strengthens self-continuity, and raises, optimism, social-connectedness, and perceived life meaning.
In 2000, researchers Chu and Downes used the above scene from Marcel Proust’s multi-volume novel In Search of Lost Time to motivate a set of testable scientific hypotheses about the role of scents in eliciting reminiscence. While many of the assertions about the structure and function of brain regions associated with olfaction remain, the field has since built consensus around a number of important functions of scent in evoking memory.
Autobiographical Memories Cued by Scent Are Emotionally Powerful
In a separate study published in 2000, Chu and Downes used either text-based cues or scents to elicit autobiographical memories among participants in their 60’s and 70’s. In the scent condition, participants were much more likely to recall autobiographical memories from ages 6-10, which is earlier than the previously documented bump in retrieval from age 10-29. In addition to being from an earlier life period, these scent-cued memories are rarer and less frequently thought about than memories cued by visual or verbal stimuli. Most importantly, scent-cued memories have more emotional content and those experiencing scent-cued memories are more likely to feel transported to the original time and place of the memory. Scent-cued memories are more likely to be positive and evoke positive emotional responses compared to memories from other cues.
Scents as Aids to Nostalgic Reminiscence
Results from a randomized controlled trial among 60 participants living in a long-term care facility published in 2020, showed that guided reminiscing about nostalgic scents led to reductions in anxiety and depressive symptoms compared to a control conversation about everyday issues. They also identified a relaxation response measured by heart rate variability.
Connected in this way to deeper emotional memory, scent among older adults may help people reconnect with a lost sense of faith and spirituality that are valuable supports during aging and in preparing for death.