Insects have a very advanced sensory system that responds to stimuli. They are capable of reacting to stimuli such as infrared and ultraviolet lights, vibrations, and ultrasound waves. It has been shown that many invertebrate animals like them feel and avoid dangerous stimuli that cause pain.
All this points to the fact that insects do indeed feel pain.
However, it does not mean that they feel pain in the same way that human beings feel it since their nervous system is different. Although their nerves are also distributed throughout the body, there may be parts that they do not reach and where, therefore, they do not feel pain. There is still much to research and learn about these small animals but various studies have already been carried out in relation to this topic.
The pain is a biological response experienced by living beings having the central nervous system. It can also be an emotional experience, which works subjectively and is different for each individual.
It is a set of neurophysiological mechanisms that send a message to the central nervous system when a part of the body is exposed to pain. Nociceptors are the nerve endings that detect the stimulus that causes pain and analyze its origin, intensity and duration. The nociceptive signal is transformed into an electrical signal called transduction so that the brain can interpret it and activate its defense mechanisms.
Insects have a central nervous system, although it is much simpler than ours and that of other larger animals. In addition, they also have the sensory organs that react to pain so they are capable of feeling it, although it is not yet known exactly in what way or with what intensity.
To find out if animals feel pain, we use the analogy, comparing our reactions and theirs to a negative stimulus. These reactions can be, for example, the flight or the increase of the heart rate.
One of the latest studies on insect pain has scientifically shown that these animals can also experience persistent pain after a healed injury. The research was carried out on the fruit fly and left evidence that it can experience chronic pain, in a similar way to humans.
In this study, the nerve in a fly’s leg was damaged and allowed to heal. Once it healed, they could see that all the legs had become hypersensitive. This happens because pain-inhibiting neurons block pain, changing the intensity with which it is felt and making the animal more alert and protective.
Insects feel pain and are also based on past experiences, avoiding approaching stimuli that had previously caused them pain.