There are two ways to feel nothing. Both ways are a matter of affectlessness, with each way having its own respective path to that point. The first way, of which I believe is the least common, is nearly a degree of ignorance. Stimuli are ignored by the subject whether it be through emotionally inebriated choice or pure laziness. I would think this affectlessness is presupposed by a state of depression: a true lack of vigor for living, and, so, caring. Perhaps the sin qua non of this type of affectlessness is a lack of frustration towards one's own self in this state, or rather, no desire to feel. I would call this state simply vacant. Vacant, as opposed to empty, because it implies something is supposed to be there.
The second path is much more peculiar, because it mirrors the first path in conclusion, but approaches in a converse dynamic. If the first state is considered a lack of stimulation, the second state can be considered as overstimulation. It, too, arrives at affectlessness through a means of threshold transition. Think about what happens when you hear a song that immediately captivates you. You may find yourself repeating the song over and over again to relive the 'high' it gives you. But, in this state of captivation, when other songs are played, they are perceived as aberrantly less. Your threshold of musical taste has transitioned in the state of captivation. I believe a similar thing happens in life. We go through experiences that positively or negatively captivate us and adjust our threshold of what affects us in the the future. To be concise, here's my main point: overstimulation, inherent in this modern era, has brought us to a point of pseudo-fullness, a simulacrum so far removed from authentic, substantial satisfaction, that we have captivated ourselves to the point of boredom, and thus ironically used our freedom to blindly render ourselves affectless.
