As far as I can tell, all that specific machine does, is figure out whether an animal already has a preference for the substance in the reward slot, or if it is susceptible to training for the reward slot. It may be useful in the sense that it can tell if an animal prefers something by its smell or senses, but it doesn’t seem like that much of a big deal.
In the old 1950s addiction experiments, it wouldn’t have made any difference at all. The rats would have figured out in probably less than a day that they can’t get water unless they chose one of the two good spigots on a four spigot apparatus. That’s not telling us anything about addiction. And once the rat figured out the smell of the drug, it’d always immediately go for the “hot” spigot if it’s addicted, or not go for the hot spigot if not. But that doesn’t tell us about how animals get addicted at all, but just what they’ll do in completely isolated circumstances once addicted.
It has no (or little) value (relative to what we already know) as an experimental apparatus once we have addicted rats. And getting into addiction isn’t the important area of study. Getting out of addiction is the real problem, right? So we want apparatus that’s able to replicate a rat’s normal life, with controllable modifications. Stuff a rat or human analog might encounter in real life. Not solitary confinement. That’s rare in both humans and rats. Solitary confinement isn’t normal. We need study modalities that don’t involve such cruelty to social creatures.
