Stuttering is a complex communication disorder defined by involuntary disruptions in the flow of speech, known as primary behaviors. These core disruptions include the repetition of sounds, syllables, or single-syllable words, the prolongation of sounds, or the complete blockage of airflow and voice. While these primary behaviors are the most noticeable characteristics, the experience of stuttering is often complicated by learned physical and verbal reactions. These learned reactions, developed over time as a response to the struggle of speaking, are known as secondary behaviors. Understanding these associated movements is important for understanding the full scope of the disorder.
The Definition and Function of Secondary Behaviors
Secondary behaviors are actions or vocalizations that a person who stutters uses in an attempt to manage, minimize, or push through a moment of disfluency. They are not an inherent part of the neurological basis of stuttering itself, but rather physical or verbal coping mechanisms that develop as reactions to the primary stuttering moments. These behaviors are initially unintentional, born from the speaker’s desperate, often unconscious, effort to regain control when feeling “stuck.”
The function of these reactions is to serve as a distraction or a perceived way out of the block or repetition. The individual feels a loss of control during the stutter, and the secondary action is a reflexive attempt to take back control of the speech mechanism. This struggling behavior can take many forms, including physical tension, facial contortions, or the use of extraneous sounds. Over time, these actions become closely tied to the anticipation or occurrence of a stuttering event, making them predictable habits.
Categorizing Secondary Behaviors: Escape vs. Avoidance
Clinically, secondary behaviors are categorized based on their timing relative to the moment of stuttering, falling into two major types: escape behaviors and avoidance behaviors. This classification helps differentiate between reactions used to break free from a stutter and tactics used to prevent the stutter from happening at all.
Escape Behaviors
Escape behaviors are actions that occur during a moment of stuttering, serving as a physical or verbal effort to terminate the stuck feeling. These behaviors are an attempt to “escape” the current block or prolongation. Examples often involve sudden, noticeable physical movements or increased muscular tension.
Common physical examples include eye blinks, sudden head jerks, facial grimacing, lip tightening, or jaw clenching. Vocal escape behaviors might involve interjecting a sound like “uh” or “um” to jump-start the word, or abruptly changing the pitch or loudness of the voice. The person is typically caught in the primary disfluency when they execute the escape behavior to force the word out.
Avoidance Behaviors
Avoidance behaviors are actions taken before the moment of stuttering occurs, with the intent to prevent the disfluency entirely. These tactics arise from the fear or anticipation of a word or situation the speaker believes will trigger a stutter. Unlike escape behaviors, avoidance behaviors are often linguistic or social in nature, designed to conceal the difficulty of speaking from listeners.
Linguistic avoidance involves manipulating language to bypass a feared word. This can take the form of word substitution, where the speaker quickly replaces a difficult word with an easier synonym. Another common tactic is circumlocution, which is talking all the way around the topic to avoid using a specific sound or word. Other avoidance behaviors include postponing speech by using excessive starter phrases like “you know,” or simply refusing to speak in certain situations altogether.
How Secondary Behaviors Become Fixed Habits
The mechanism by which these initial reactions become fixed, automatic habits is a process known as negative reinforcement. This behavioral loop explains why the person continues to use the behavior even though it does not truly improve fluency. The cycle begins when the speaker anticipates or enters a moment of primary stuttering, which is an unpleasant or tense experience.
The speaker then uses an escape or avoidance behavior, such as blinking hard or using a filler word. If the stuttering moment ends immediately after this secondary behavior, the brain registers the action as the cause of the release. Even if the word was released purely by coincidence, the brain is instantly rewarded by the temporary termination of the unpleasant stuttering moment.
This reward reinforces the physical or verbal action, increasing the likelihood that the person will repeat the behavior the next time they anticipate or experience a block. Over many repetitions, the secondary behavior moves from a conscious effort to an ingrained, automatic habit that is performed without thinking. These conditioned responses can eventually become more noticeable and distracting than the primary stuttering behaviors themselves.