Death. Nobody can escape it, and nobody knows when it’s coming. Or do we? Many people speaking of their loved ones who have passed away will tell you that they have noticed a change in behavior some time prior to their death.
People who are near death exhibit a change in behavior sometimes even weeks before it actually happens. While some argue that this is a pure coincidence, there are those who are certain that people know when death is near.
One thing is certain though: Science has proven that we are able to smell death. We don’t necessarily have to know what that smell actually is, but we certainly react to it.
If you thought that your sense of smell is conditioned by what you can consciously interpret, think again. It turns out that we are capable of detecting a wide spectrum of smells, many of which we don’t know how to interpret, but react to in very particular ways.
In fact, humans are able to detect chemo signals, which can be identified as threats, fear, attraction. These ‘smells’ can be so subtle that we may not recognize them as actual smells, but we definitely react to them.
Such is the case with smelling death. When a body starts decaying, the decay results in a scent produced by a chemical called putrescine. The scent of this chemical results in animals exhibiting necrophobic behaviors, and these responses are thought to have evolved at least 420 million years ago.
Certain animals associate the smell of putrescine to two kinds of danger: the first being that a predator is nearby; and the second that certain pathogens present can put them in a life danger if physical contact is established.
In both cases, these animals respond by avoiding or leaving the area. Now, scientists wanted to see if humans possessed the same ability of detecting, and the same behavioral response to the smell of putrescine.
A study done on the behavioral effects putrescine has on humans has shown that we are no different from the way animals behave when exposed to the scent. They did four different experiments, which included putrescine, ammonia, and water.
In the first experiment, the scientists tested the participants’ vigilance after a brief exposure to the scent of putrescine. The results showed that the participants showed a heightened vigilance, or in other words, they reacted more quickly, compared to those exposed to ammonia and water.
The research team conducted this experiment on an unsuspecting group of people, who were given the task to rate a smell on its intensity, repugnance, and familiarity. However, what they wanted to see is how fast the participants would walk away at an 80m distance.
The result of this experiment showed that the participants who smelled the putrescine, tended to walk away more quickly from the site, proving that the smell evoked a strong motivation to escape.
Escape– and threat-related cognition
In another experiment, the research team gave the participants to complete a word stem-completion task after being exposed to the smell of putrescine.
The results showed that the smell of putrescine caused the participants to complete the word stems with a frequent use of escape words. The smell also led to an increased use of threat words.
Defensiveness and hostility
The last experiment exposed the participants to a very subtle scent prime that they couldn’t detect. In this experiment, the participants were given a text to read, after which they were to evaluate the author.
Although they were not able to detect the smell of putrescine, the participants showed defensiveness and even hostility toward the author. This result showed that non-conscious exposure to the smell evoked a defensive behavior in the participants.
This study proved that people are indeed affected by the smell of putrescine, the ‘death’ chemical, both consciously and subconsciously. It turns out that we are indeed able to literally smell death and react to it in a very particular way.
Have you sensed death in someone you know some time before they passed away? Perhaps we all do, but we are unable to interpret our default reactions as those of feeling death.
Creepy. Isn’t it?
Source: Wisman, Arnaud, and Ilan Shrira. “The Smell of Death: Evidence That Putrescine Elicits Threat Management Mechanisms.” Frontiers in Psychology 6 (2015): 1274. PMC. Web. 24 May 2017.