Taking refuge in your base function
When we are stressed, or uncertain as to what to do, or impatient, or depressed, I think we are inclined to take refuge in what we know best, our base function.
Here are some examples of how that may work:
:Te: - finding something to do that you can do well (even if not really what has to be done in the circumstances); reading about something you consider useful; talking to others about it.
:Fi: - connecting to people; contacting old friends or connecting to new ones; perhaps starting a new friendship/relationship
:Ne: - getting into a brand new subject of interest
:Se: - decisive action to re-establish sense of dominance over a situation, sometimes something as simple as telling someone off
:Si: - doing something sensorially pleasant, perhaps just relaxing in a pleasant environment doing nothing
:Ni: - giving oneself time to reflect over things, or finding ways to connect to inner impressions; mind-wandering into the past, imaginary worlds, "writing books" in your mind
(from the point of view of the external observer, :Ni: and :Si: may lead to identical activities. For instance, a walk in the woods: for :Si: it would be the immediate pleasant surroundings, for :Ni: because the quietness may facilitate getting into the inner reflective mood)
:Fe: - going to environments where the emotional atmosphere is the one they want to be at the moment? Typical example: going to a party to raise your mood?
:Ti: - plunging into things like mental exercises or mathematics (this is a bit lame but I couldn't think of anything better)