Yes indeed, I very much enjoyed reading Usler's (PhD) research: "*Why Stuttering Occurs: The Role of Cognitive Conflict and Control*" (2022). I [summarized ](https://www.reddit.com/r/Stutter/comments/15cl7wd/tips_to_improve_stuttering_from_the_research/) it and turned it into a [model](https://www.reddit.com/r/Stutter/comments/18p4piy/happy_new_year_cheat_sheet_helpful_interventions/#lightbox). As far as I’ve read, researchers discuss this defensive mechanism using various terms. Most of them refer to it by different names, such as inhibitory mechanism, threshold mechanism, release threshold, defensive mechanism, etc. Evan Usler had actually created a [scientific diagram ](https://drive.google.com/file/d/1SH7PFQ0K-8wud77vzL6cBHILXrPhE78X/view?usp=sharing) that visualizes a **threshold** mechanism. In Evan User's research, he states: >*"This dynamic may create a vicious cycle in which excessive use of cognitive control via the BIS (behavioral inhibition system) creates more cognitive conflict than it resolves, resulting in an increasingly destabilized speech motor system, increased anxiety and arousal, and greater instances of stuttering-like disfluency*" "*A speech block occurs if cognitive conflict passes a THRESHOLD resulting in shutting down initiation of the speech motor program at the onset of articulation. This behavioral inhibition system leads to maladaptive activation of the right-hemisphere in people who stutter. People who stutter* exhibit widespread hyperactivity across neural correlates of inhibitory control*." "***Why are stuttering-like disfluencies perceived as a loss of control?** *The mechanism of freezing is a defensive behavior involving the sudden stopping of speech movement to a perceived threat. The freeze response is accompanied by motor inhibition and reduced heart rate (i.e., coactivation of sympathetic and parasympathetic arousal) and decreased responsiveness to external stimuli. This freeze response may best be conceptualized as a hypersensitive and maladaptive emergency brake if articulation begins before cognitive conflict is resolved.*" >"Saying one’s name should be a well-learned and effortless task, but the communicative responsibility of such an act often results in excessive use of controlled processes for execution. Developmental stuttering is associated with a chronic state of heightened **cognitive conflict** and control during speech. **Cognitive conflict** refers to inconsistencies between action-based cognitions, such as decisions, motivations, or expectations, that interfere with goal-directed behavior. **Cognitive conflict** includes “low-level” incongruent representations in language processing (i.e., linguistic conflict) and “high-level” inconsistencies in motivational state. Linguistic conflict may result from activation of competing semantic or phonological representations during language processing. For example, adults who stutter exhibit an inhibitory control deficit that impairs lexical selection. Motivational conflict (i.e., approach-avoidance conflict) involves simultaneous yet opposing motivations to approach and avoid a situation, such as giving a public speech despite fear of social evaluation. If motivational conflict is not resolved before the onset of articulation, an emergency braking of the motor system occurs during speech initiation (aka blocks and prolongations). Over time, anticipatory anxiety, physical tension, and the feeling of loss of control become habitual in response to the chronic cognitive conflict and transient freezing of speech initiation."