Great reply! I agree with much of what you say. Regarding the variable nature of triggers. Firstly, I believe that we could have an infinite number of triggers. But, I do think there to be 2 main triggers: anticipating negative reactions (**external stimulus**), and anticipating communication failure (**internal stimulus**). I think that there are two factors that determine whether the brain allows or prevents the execution of (a part of) a speech plan. 1. how highly activated the speech plan is (although, this doesn't seem to be a problem in stutterers I believe) 2. how high the execution threshold is (this fluctuates based on our interpretation of stimuli in that specific moment for that anticipated motor program or word) In my opinion, triggers result from past experiences of one’s speaking leading to negative consequences: they increase our tendency to negatively evaluate our speech performance or listener reactions. Additionally, triggers are.. as far as I understand it, paradoxical in nature - based on how we interpret the neutral stimulus on a moment-to-moment, or word-to-word basis. I see it like this, every (fraction of a) second the neutral stimulus (e.g., "feared word") might transform into a conditioned stimulus (i.e., a trigger) - based on the net positive associations we attribute to them (e.g., based on the perception of the importance and accuracy required for our speech).  If the negative associations outweigh the positive ones, it becomes net negative (i.e., poorly fine-tuning of the release-threshold mechanism to increase the execution threshold). If there are more positive evaluations than negative evaluations the release threshold goes down, and it becomes easier to execute the speech plan. Contrary, if it's net negative, the release threshold increases too high to sufficiently activate the speech plan. We then perceive an error in the speech plan. Trying to execute the speech plan when they are not ready to be executed - results in us being unable to say the word. If we believe that the speech plan contains errors - then we might respond to it in different ways: (1) We might cancel the speech plan: we give up and decide to substitute different words (2) Or, likely in most cases, we do not cancel speech plans, but rather we just keep trying to execute the same speech plan. If we succeed (if the speech plan does indeed eventually become sufficiently activated) then we say the planned utterance fluently. If we fail (if the speech plan never becomes sufficiently activated) then stuttering occurs. Often we reformulate or repeat the same speech plan until it ends up error-free. However, this strategy is not effective to make the speech plan free of perceived errors. (resulting in speech blocks that are highly unnecessary). Resulting indirectly - as a consequence - in speech blocks (i.e., the inhibition of speech motor execution which is the failure of the speech plan to execute). I believe, that most likely, the real problem appears to be - that we have a tendency to evaluate our speech plan with the goal of the brain allowing or preventing execution of the speech plan (i.e., an appriopriateness regulator, for example, to make it more socially appropriate).  I think that we likely wouldn't have much of a problem with the subjective feeling of loss of control and the inability to initiate or move forward with articulation - if (1) we didn't have this tendency, (2) we didn't attempt to avoid the perceived stimulus for speech execution to proceed, or (3) we simply forget our mistakes to reduce negative associations (and instead, remember the good parts). Here is a practical example - how I see it: Let's say that I have to say my own name, or a certain word starting with the letter Z ("a feared, anticipated word"). This stimulus ("a feared word") is characterized by a lack of faith in my ability to speak: leading me to perceive that my speech is not good enough - which may then cause myself to mistrust my (feed-forward) motor-programs and instead to rely excessively on auditory feedback (automatic processes become controlled processes). In this way I may become excessively perfectionistic and sensitized to my speech that doesn’t conform to my ideal - increasing the release threshold too high where I'm unable to say the planned word.