Odor Can Help Trauma Even Though It Can Cause It

Fear. Humans and animals both feel it, whether it’s a danger to your life or something that makes you afraid. Many ways fear can be triggered, and one way is through Odor. There is a phenomenon, and it is called the Proustian Moment. This means that memories from the past were hidden and long forgotten. They are brought back to the present all at once. In one moment, due to the trigger of smell attached to the memory (Walsh 1). This was said in the article, What the Nose Knows by Colleen Walsh; smells are handled by the olfactory bulb, which then informs the other parts such as the limbic system and the amygdala. Both emotion and memory take a role in the fear that Odor triggers. 

A study was discussed by Dr. Grella, who outlines how Odor does impact memories. From the article, Odor modulates the temporal dynamics of fear memory consolidation. The smell allows the memory to recall the memory that one has, which is feared. An experiment was done on female and male mice testing their c-Foss and recall levels from the dorsal and the prelimbic cortex. Some mice were tagged with Odor, and others were non-odor associated. They concluded that Odor does influence fear of memories (Grella 2). 

With Odor triggering the fear memories, it can cause PTSD/Trauma. It can occur after a while or a couple of years because Odor is connected with fear when encoded. Although smell can trigger Trauma, it has been said that smell can also treat Trauma. The article, Smell Changes Memory Processing and Could Treat Trauma by Medical New Today. An experiment was done on mice just like Dr. Grella had done. A group of mice was electrically shocked, but half of the mice were exposed to an almond scent. The following day, the researchers discovered that when they brought out the almond scent, they remembered the small shocks they were given from the previous day. The same experiment was done 21 days later, but something different had occurred. Due to the smell, the almond scent, the activity was shifted from the prefrontal cortex to the hippocampus making it more hippocampus-dependent. This can allow ways to engage and disengage the hippocampus and with the help of drug or behavioral treatment. This can enable them to help suppress fear memories, which can help those who suffer from PTSD and Trauma. 

I did not expect this when I was reading the article. I was shocked that smell itself is the problem and can also help the situation. With that saying, it can be said that those that do have fear-induced memories due to Odor can improve their PTSD/Trauma in the future with the help of Odor itself (3).

By: Eesha Chohan

Links: 

1. Walsh, Colleen. “How Scent, Emotion, and Memory Are Intertwined - and Exploited.” Harvard Gazette, Harvard Gazette, 27 Feb. 2020, https://news.harvard.edu/gazette/story/2020/02/how-scent-emotion-and-memory-are-intertwined-and-exploited/. 

2. Grella, Stephanie., et al. “Odor Modulates the Temporal Dynamics of Fear Memory Consolidation.” Learning & Memory (Cold Spring Harbor, N.Y.), 2019, U.S. National Library of Medicine, https://pubmed.ncbi.nlm.nih.gov/32179657/. 

3. “Smell Changes Memory Processing and Could Treat Trauma.” Medical News Today, MediLexicon International, https://www.medicalnewstoday.com/articles/smell-changes-memory-processing-and-could-treat-trauma#1.