All the comments discussing the moral implications of harming insects are focusing on the wrong part of how useful this information is.

As the link says, this research indicates that we can use insects to do basic research on Neuropathic pain. Insects, being easy and fast to breed, and easy to manage in large quantities, makes this especially useful for research.

Now they can try all sorts of methods of tackling the problem, from drugs to gene therapy.

It's not, of course, proof that successes will translate to mammal or human models, but it's an excellent way to do some initial concept filtering.