That kind of seems to be a red herring, though, in the absence of such buttons. It's an empirical matter and one that is worth paying close attention to, but it seems to me that for a large number of people the ego, the super-ego, the pre-frontal cortex, and the many shards of Azathoth are all different and difficult to differentiate. I know that I internally use the notion "I [egosyntonicly and upon reflection] want to do X" ("I desire taking action X or set of actions X", "We, the spaciotemporal coalition of mind fragments who are currently reflecting, want to do X") when I at least partially mean "I want to signal virtue Y", "I want to be seen as a person who does things like X", "I am afraid of being seen as a person who doesn't do X", "I am afraid of being seen as a person who doesn't possess virtue Y", "I am afraid of being seen as someone who doesn't believe virtue Y is desirable", "I am afraid of not doing X", "I want to believe that I want to do X", "I am afraid of the consequences of not believing that I want to do X", et cetera ad nauseum. (Same for "I want to be (adjective)", "I want to be a (adjectival noun)", "I want to possess (concrete or abstract noun)", et cetera.)

ETA: (I use "am afraid of" where perhaps I should use "find aversive", the latter being more general and more accurate. Fear is a similar but narrower phenomenon, I think, more Near and less Far than the most common kinds of aversion.)

The point being that each of those interpretations of my "want" emphasizes a mechanistically and possibly neuroanatomically different source of attraction and/or aversion, the conglomeration of which is difficult to break down into pieces and thus difficult to analyze to determine the 'biggest' causal factors therein. It is unclear to me whether or not the Pareto principle applies to the analysis of the sources of egosyntonic aversion/attraction, and it is also unclear if empirical introspection is enough to truthfully identify the biggest causal factor in the event that the Pareto principle does in fact apply.

EATA: I remember thinking that a modernized and skillfully interpreted version of Jungian psychology would be useful for doing this kind of introspection.