Emotions like fear is not limited to humans alone. Even very minute insects like a fruit fly can demonstrate the same feelings when confronted with the same conditions. This is according to a new study by California Institute of Technology (Caltech).
The researchers did it by studying the phenomenon by dissecting the emotion idea into individual basic parts which is called emotion primitives.
“There has been ongoing debate for decades about what ’emotion’ means, and there is no generally accepted definition,” said lead researcher David Anderson. “We put forth the view that emotions are a type of internal brain state with certain general properties that can exist independently of subjective, conscious feelings, which can only be studied in humans,” he added.
William T. Gibson, the lead author explained that emotions can be segregated into primitive emotions same way as secondary colors such as orange can be separated into two primary colors which are red and yellow. The emotions primitive studied in flies can be explained in the same context of a stimulus associated with fear in humans for example those of a gunshot.
If you happen to hear of a gunfire, the sound itself will induce negative emotions. This primitive feeling is identified as valence, might as well be, because your behavior will be altered for several minutes after undergoing the experience. This is emotion primitive is called persistence.
Repeated experience to the same stimulus could also result in a greater emotional response- another primitive aptly called scalability. If for example you heard 10 gunshots instead of one, you will display more fear than just hearing one gunshot which is another primitive called generalized to different situations.
You might be doing anything when you heard the gunshot again. You won’t be able to finish eating because of that gunshot and the fear of it. The researchers opted to study all these stimuli by observing the insects in the presence of what they call fear-inducing stimulus.