I take it as obvious that signaling is an important function in many human behaviors. That is, the details of many of our behaviors make sense as a package designed to persuade others to think well of us. While we may not be conscious of this design, it seems important nonetheless. In fact, in many areas we seem to be designed to not be conscious of this influence on our behavior.
But if signaling is not equally important to all behaviors, we can sensibly ask the question: for which behaviors does signaling least influence our detailed behavior patterns? That is, for what behaviors need we be the least concerned that our detailed behaviors are designed to achieve signaling functions? For what actions can we most reasonably believe that we do them for the non-signaling reasons we usually give?
You might suggest sleep, but others are often jealous of how much sleep we get, or impressed by how little sleep we can get by on. You might suggest watching TV, but people often go out of their way to mention what TV shows they watch. The best candidate I can think of so far is masturbation, though some folks seem to brag about it as a sign of their inexhaustible libido.
So I thought to ask the many thoughtful commentors at Less Wrong: what are good candidates for our least signaling activities?
Added: My interest in this question is to look for signs of when we can more trust our conscious reasoning about what to do when how. The more signaling matters, the less I can trust such reasoning, as it usually does not acknowledge the signaling influences. If there is a distinctive mental mode we enter when reasoning about how exactly to defecate, nose-pick, sleep, masturbate, and so on, this is plausibly a more honest mental mode. It would be useful to know what our most honest mental modes look like.
If the ancient (proto-human) mental construction of 'self' was a remodeled and turned inside-out version of the 'other people' mental construction, the distinction between signaling to nobody and signaling to yourself may not be on as sturdy grounds as it seems.
The idea seems to make sense: Evolution doesn't jump in huge strides, so the progress from not-having-a-self to having-a-self must have been a cumulative one. The only place for similar parts to be worked on an advanced is within social behavior with your group, so that at least seems reasonable at the surface. Dennett suggests the role understanding our peers played in eventually training us in how to understand ourselves in 'Consciousness Explained', 'Darwin's Dangerous Idea', Dawkins mentions things like this in 'The Ancestor's Tale', and in Clegg's book 'Upgrade Me', he cites a similar human origin story.
So even when you are alone, you are still communicating and possibly signaling to an audience of one, perhaps. You are signaling to the entity you understand to be yourself the behaviors and actions you believe to be socially (personally) acceptable for you to perform within the confines of the private, one person audience.
It may sound strange but with the evolutionary underpinnings the 'self' may not be so wholly divorced a concept from the 'other people' as we thought. Since these behaviors only seem to indicate a change in expectations rather than a release of all social restrictions and responsibilities, I am not sure that these activities really signal a clearer and more rational state of thinking -- just a different audience, different game. Just being alone doesn't necessarily strip off the animal reasoning.
Perhaps less resources are devoted to the social game and that would be a legitimate reason to trust someone's reasoning more, but then there are benefits to social reasoning too.