A psychiatry professor who specializes in autobiographical memories says that directly engaging the sense of smell may help derail runaway negative thought patterns and reduce feelings of depression.
Previous studies have noted the potency of targeted smells on memory recall. However, this new study is the first to identify a link between smells associated with positive autobiographical memories and reduced feelings of depression.
Hunting for a Link between Sense of Smell, Memory Recall, and Depression
In modern psychiatric medicine, depression is often treated with prescription medications. More holistic approaches often include exercise, meditation, and even customized nutrition plans, while more experimental approaches include using targeted electrical signals or consuming magic mushrooms. Some research even indicates depression could be treated with placebos alone. Either way, nearly all approaches include some form of talk therapy.
In many of the popular approaches, the clinician will attempt to guide the patient to recall more positive memories. While this approach has been shown to work in some situations, the continued prevalence of both medicinal and holistic options indicates it has its limitations.
When studying autobiographical memories, Dr. Kymberly Young found it interesting that patients suffering from depression often had a much harder time recalling positive memories than those not battling depression. Dr. Young was also aware of research that showed activating the region of the brain known as the amygdala with strong odors could trigger memories that patients described as feeling more vivid and more real than memories triggered by word cues. Somewhat surprisingly, the University of Pittsburgh professor found almost no work that combined these approaches to aid positive memory recall in patients fighting depression.
“It was surprising to me that nobody thought to look at memory recall in depressed individuals using odor cues before,” said Young.
Clinical Trial Shows Promising Results
In an effort to better understand the link between the sense of smell and memory recall as a means of treating depression, Young and a team of researchers asked study volunteers to smell the contents of opaque glass vials that contained potent yet familiar scents. This included things like the smell of oranges, coffee, shoe polish, and Vicks VapoRub.
After smelling each vial, the researchers asked the study participants to describe any triggered memories. Significantly, the volunteers were asked to include both positive and negative memories. As hoped, the work yielded some significant results.
First, memories triggered by smells were described as more potent and more vivid than memories triggered by word cues. This finding was consistent with the professor’s own previous research into memory.
Second, memories triggered by smells were often very specific. For example, the smell of oranges might trigger a recent memory of eating an orange with a friend rather than a general memory of having eaten oranges before.
Third, the study subjects were more likely to recall positive memories as opposed to negative ones, something the researchers noted was a significant finding.
Finally, and perhaps equally significant, the study found that volunteers who reported feelings of depression had dramatically improved recall using smell cues rather than word cues.
When added together, the researchers say these results showed that “scents are more effective than words at cueing up a memory of a specific event and could even be used in the clinical setting to help depressed individuals get out of the negative thought cycles and rewire thought patterns, aiding faster and smoother healing.”
Brain Scans and Treatments for Depression
Although the study, which is published in the journal JAMA Network Open, was admittedly low-tech, Young says the results clearly show a strong link between vivid, positive memory recall and targeted smells. Also significant, the study reaffirmed that strong smells were more effective in triggering positive memories than word cues used in talk therapy.
Next, the researchers hope to employ real-time brain scans so they can observe the activity in the amygdala when volunteers smell potent smells, especially smells that trigger positive memories.
Moving forward, the team says there is still more work to be done before clinicians begin using potent smells to trigger positive memory recall or even to derail runaway negative thoughts in patients battling depression. Still, they are already encouraged by the study’s initial results and believe that a better understanding of memory and the issues faced by patients battling depression will inevitably lead to improved treatment options.
“If we improve memory, we can improve problem-solving, emotion regulation, and other functional problems that depressed individuals often experience,” Young said.
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.