Evidence that insects can also feel pain following injury or injury was found by a scientist at Sydney University, Greg Neely, and his team. This is the first research that shows that even insects experience chronic pain, which is a pain that can last over time, usually those caused by injuries and causing non-fatal damage.
The researchers carried out experiments on Drosophila, the so-called fruit fly, showing that the latter can also perceive a persistent pain that lasts after the wound has healed. In humans, the pain can be of two forms: inflammatory or neuropathic. In the insect, the researchers analyzed the neuropathic one, a pain that can occur in humans, for example, in case of spinal cord injury, neuralgia, diabetic neuropathy or accidental injury.
After damaging the nerve of an insect’s paw, the researchers waited for the wound to heal completely. Following the recovery, the researchers discovered that the other legs and the fly had become hypersensitive. As Neely himself specifies, this is to be explained by the fact that after the wound, the other legs, thanks to hypersensitivity, try to protect themselves so as not to suffer the same kind of damage.
Then, by genetically analyzing the gnat’s reactions, the researchers found that his brain receives painful messages via sensory neurons through the ventral nerve cord, a sort of version of our spinal cord, as Neely explains: “After the injury, the injured nerve discharges all its load into the nerve cord and kills all the pain brakes forever. So the rest of the animal has no brakes on his “pain”. The threshold of “pain” changes and becomes hypervigilant.”
The loss of pain brakes is extremely important for many animals in order to survive in many dangerous situations, the scientist specifies.
This research could serve, as the researchers themselves hope, for the development of new drugs or stem cell-based therapies in the treatment of chronic pain.