Honestly, Sociopath was a strange and unsettling read. At times it comes across almost like a novel, with reconstructed scenes and dialogues. Gagne makes the excellent point that there is a lot of grey around the diagnosis and even the definition of sociopathy. Is it the same as psychopathy, just further down the spectrum? The same test is used for assessment, but there is apparently a vast gulf between psychopathy and 'normal,' which is presumably where sociopathy sits. Gagne likes to define sociopathy as a kind of learning disability, but for emotions -- empathy, jealousy, compassion can be learned, but with difficulty (anger and happiness come more easily, at least for Gagne).
Gane talks al lot about 'apathy,' which I found quite confusing -- sometimes it's good, sometimes unbearable. I must admit I became a bit lost at times as Gagne described her strategies for relieving the weight of apathy, though her descriptions of the rising tension, which could only be relieved by 'bad' actions (stealing a car, stabbing a classmate with a pencil), reminded me a lot of Gabor Matè's account of the unbearable tension of distress experienced by the drug users he works with. Whatever the origin of these impulses, it seems clear that the brain uses a similar mechanism to try to relieve its pain.
By the end of Sociopath, I can't claim that I understand sociopathy much better than I did, but I do have more sympathy for this maligned minority.