Neural Mechanisms of Accumulation and Triggering What is the mechanism by which the brain/mind 'accumulates' a felt-sense to a point of 'triggering' an action?

For example, if unable to complete a task (e.g. opening packaging), a person can feel increased frustration for each attempt at the task.  Eventually, the level of frustration will reach a 'trigger-point' and a compensatory action ('will you open it for me?') can occur.

I see this in many areas of human life (though frustration is the most common/obvious example), so I would suspect that it's a general principle of neural action than a specific mechanism of tracking sensory perceptions.

Also, apologies for any unclear language or concepts.  I will happily rewrite if necessary.

[EDIT]:
For clarity, I'm more curious about the 'accumulation' and less about the 'triggering'.  Also, with regards to accumulation, I'm particularly curious about accumulation over longer time periods.  So, not just task-specific frustration (as an example), but also things such as life skills.  

So, another example: talking to a specific person, you notice that they have some behavioral quirk that irks you.  Over time, you feel more and more irked by this quirk.  (Hrmm.. irk, quirk, maybe I need different words...), to the point where you avoid interacting with this person due to their irksome quirk.

I am semi-assuming that the mechanism involves an increase in conscious or subliminal attention to the offending perception, thus creating a sensation of increased salience of the stimulus.  But...I don't want to assume too far, and I'm curious if the subject has been formally explored.
There is a model of neural mechanisms of accumulation and triggering in the domain of perceptual choice called the leaky competing accumulator (Usher and McClelland, 2001) model. It uses decision units that fire when sufficient evidence has accumulated. Ratcliff and McKoon (2008) pointed out that LCA associated with their Diffusion model accurately modeled the neural firing rates observed in monkeys before a decision was made (see section 10 of the article, a monkey moving his eyes to a target that competed with a non-target stimulus).

The processes described in LCA are also found in different theoretical account of decision making. You may find some models in this wikipedia page summarizing the decision field theory of Busemeyer &amp; Townsend (1993).

Your question mentioned a longer time scale than the one addressed by the above references. I don't know a model of accumulation/decisions that span over hours/days/years. For example, the one here, despite its promising title ('From perception to action: an economic model of brain processes'), is not interested in the temporal aspect of the decision (i.e. accumulation phase).