I once posted a highlight of my thoughts on how dogs use their nose to discriminate scents. It is my belief they detract scents before they discriminate. For now it is only a hypothesis and I hope in short time we will come up with some funds to experiment on a larger scale.
It is my general belief detraction is when the dog suppresses the most common elements first when given the task of finding something. From there it (for lack of better terms) it "logs" the targeted scents it is looking for AND "logs" new scent particles for further discrimination. If the substance has the scents that are similar to the target scent even if not a pure scent the dog can recognize it. We don't know exactly how a dog catalogs scents. For my own mind and understanding I have made a guess that seems to be holding up.
I will use color marbles represent scents and to better illustrate what I think:
Imagine the scents as marbles. The non-targeted scents represent the most marbles so they are pure white.
Now imagine any scent the dog is looking for as shades of red marbles. With a limit that individual dog uses to define "red". The street narcotics have the full range of red and can be represented from the brightest most pure form to the remaining “contaminates” of the scent as the shades. The psuedo represents perhaps ONE or TWO of those shades of red but not quite the full range of the exact street narcotic.
When the dog is trained to find the "shades" of a scent the dog looks for this representation. When the dog is trained to find only the most pure form of the targeted scent found in the real narcotic it detract the common scents and perhaps the cut off of the shades of the scent with it but finds what is needs and indicates.
If the scent is new and pure and the dog has experience with "other" pure scents like those found in psuedo it will based on its previous experiences "being a creature of optimism" and may try to indicate it.
I don’t know the exact process of how sigma chem. makes the psuedo narcotic "shades" but I do think it is an isolated fraction of the real scent.
When the dog is trained on street quality narcotics with all its impurities the dog catalogs the entire scent with impurities so it is looking for the close patterns and allowing more "marble variances" so when asked to find psuedo it says..."Um well...one "scent/marble" but where are the others?
Some will decide, especially those dogs proofed away from false finds, not to indicate the isolated scent.
Now, just the opposite happens (I think) for some dogs trained on psuedo.
The dog notices pure isolated forms and thinks, "Ah ha...PAY DAY!"
It is logical to assume some pure or chemical scents fool the dog. This is maybe because of the purity (too clean) or there are similar scent “shades” during the breakdown of certain substances like aspirin. It is possible, I believe, to further refine and proof the dog away from pure form substances when combined with the use of the real drugs but why bother with it.
The real narcotic is without question. I know others have had great success still there is too much icon worshiping in the dog world. Good trainers deserve respect a pioneers but not as gods or least you find yourself shelved. The question of psuedo use is in fact in question and it os only a matter of time before this question is enough “doubt” I think.
A dog teaches a boy fidelity, perseverance, and to turn around three times before lying down. - Robert Benchley
In order to really enjoy a dog, one doesn't merely try to train him to be semi-human. The point of it is to open oneself to the possibility of becoming partly a dog. - Edward Hoagland