You're right in saying that even though if one were a sociopath, that they can force themselves to help others anyway and such regardless of the fact that they derive no pleasure from it. Now you said that there is greater pleasure in helping others and such. But for such a person here who is a sociopath, the greatest pleasure will and always will come from their own self-focused desires in life regardless of how much they choose to help others. This would be because if you were to have a severe mental disorder (which would be not having or having very little function of certain brain processes--in this case, having little or no empathy for others and having little or no pleasure in helping others and things like this), then no amount of helping others and such can ever give your life a sense of greater pleasure. Again, the greatest pleasure will always come from your own self-focus in life. I realize that choosing attitudes and actions in life create greater function in certain brain regions (in this case, the attitude and actions of a sociopath choosing to help others which would create greater function in processes in the brain that are responsible for deriving pleasure and such in helping others). But the fact of the matter is that people with severe mental disorders are very likely to never be able to fully recover such processes in the brain and never eventually have greater function in these processes of the brain. This would be because these processes are either so far diminished or damaged.