The science of fear
Published: Thursday, June 21, 2012
Updated: Tuesday, July 17, 2012 12:07
In an effort to learn how human beings feel fear, scientists have discovered the chemical composition of fear pheromones released by fish.
It is concluded that fear is perhaps the most primitive of our feelings, it exists so that we can stay away from danger.
Scientists Ajay Mathuru and Suresh Jesuthasan from the Biomedical Sciences of Singapore have recently conducted research regarding how fish perceive fear.
Recently, scientists have been studying how animals communicate during dangerous situations.
Through research Mathuru and Jesuthasan believe that when a fish is injured, it releases certain chemicals that produce alarm in others.
In other words, fish might be able to “smell” fear.
This theory is not new to the science field, since the famous ethologist Karl von Frisch studied the behavior of minnows in an artificially fearful environment.
Frisch theorized that a chemical substance is released when fear arises, yet he never concluded the chemical composition of this substance and only called it scary stuff.
Recently, Jesuthasan and his colleagues conducted an experiment where they isolated sugar molecules called chondroitins from the outer mucus of zebra fish.
These molecules are broken the same way that if they are when a fish is injured.
They were added to the water, where the zebra fish quickly reacted in the same way to previous experiments.
At a low concentration the fish reacted by being slightly perturbed, but when a high concentration was present they froze in fear for an hour or longer.
In other words, the fish sensed the substance and perceived they were in a dangerous situation.
In animals, they send danger signals to their fellow fish, these signals are called fear pheromones. Many lower animals, such as ants and honeybees release fear signal pheremones.
These fear pheremones are not well understood, there are still question about what their chemical make up is, where the pheremones are produced, and how the pheremones are precieved.
Each species have specific fear pheromones.
What may be picked up as a danger signal to one species might not even be recognized by another.
This experiment may lead to a higher understanding of fear in other animals and even humans said Lisa Stowers, a neuroscientist at Scripps Research Institute.
The understanding of fear and panic in humans may lead to better treatment of patients who are more prone to panic attacks and anxiety.
In humans, the theory that fear pheromones exist within us is still controversial among scientists.
In zebra fish, the part of the olfactory bulb, the nerves that smell this fear pheremone, is connected to the part of the brain called the habenula.
This part of the brain may have a key role in the regulation of fear.
While little is known about this part of the brain in humans, now that this new discovery has been made, new paths towards the study of fear in humans have been made.
Perhaps in a few years we may finally know if we have fear pheromones just like observed in animals.