PITTSBURGH — Certain scents from the past instantly conjure up memories from years ago. While the connection between the human olfactory system and memory is well-documented, new research now suggests familiar smells and the memories they bring with them may help fight off depression and negative thoughts.
Study authors from the University of Pittsburgh say catching a whiff of a familiar smell can help depressed individuals recall specific memories, potentially helping them fend off negative thought patterns and embrace a better mood.
Researchers say scents appear to be more effective than actual words when it comes to provoking a specific memory of a given event. They speculate that smells may even be useful across clinical settings as a means of helping depressed individuals rewire their thought patterns, ultimately facilitating faster and smoother healing.
Dr. Kymberly Young is a neuroscience researcher focusing on autobiographical memories. Early in her career, she discovered that engaging the amygdala, or the reptilian part of the brain responsible for controlling not only “fight or flight” responses but also placing attention and focus on important events, assists with memory recall. She also points to growing pre-existing evidence suggesting people with depression have a hard time remembering specific autobiographical memories. Meanwhile, among healthy people, odors tend to trigger more vivid memories. This is likely because smells engage the amygdala through nerve connections originating in the olfactory bulb.
“It was surprising to me that nobody thought to look at memory recall in depressed individuals using odor cues before,” says Young, senior author of the study and associate professor of psychiatry at Pitt, in a media release.
So, Dr. Young decided to test out if engaging the amygdala would help depressed people better access their memories more effectively. However, instead of using costly and often inaccessible brain scanner tests, the research team opted to go low-tech.
The study authors presented a group of participants with a series of opaque glass vials containing potent familiar scents. Scent examples included oranges, ground coffee, shoe polish, and Vicks VapoRub. After smelling the vials, participants had to recall a specific memory, either good or bad.
Dr. Young noted, to her surprise, that memory recall turned out to be stronger among depressed individuals who received odor cues instead of word cues. Those given odor cues were more likely to recall a memory of a specific event (for example, going to a coffee shop last Friday) than more general memories (that they have been to coffee shops before). Memories sparked by smells also tended to be much more vivid, feeling more immersive and real. Importantly, Dr. Young adds that even though she didn’t tell participants to specifically recall positive memories, they were much more likely to remember positive past events.
Moving forward, Dr. Young plans to conduct more technologically advanced studies using a brain scanner with an eye toward proving scents help engage the amygdala of depressed individuals in a stronger manner than words. In the meantime, she’s quite happy with the progress made by this latest report.
“If we improve memory, we can improve problem solving, emotion regulation and other functional problems that depressed individuals often experience,” Young concludes.
The study is published in JAMA Network Open.