Most of the time, these dysfluencies go unnoticed and don't really interfere with communication. Distinguishing stuttering from normal dysfluency On the surface, stuttering differs from normal dysfluency in the type of behavior, amount of behavior, quality of behavior, and reason for behavior. People who stutter use different kinds of dysfluencies than normal speakers, use a greater amount of dysfluencies, have different qualitative characteristics to their dysfluencies, and use dysfluencies for different reasons than people who do not stutter. Certain dysfluencies are considered more characteristic of stuttering than of normal speech and these dysfluencies are often referred to as the core stuttering behaviors. The three classic core stuttering behaviors are part word repetitions, prolongations, and blocks.
Prolongations have audible sound, as opposed to blocks, which are usually inaudible.
They disrupt the integrity of a word. Although part word repetitions, prolongations and blocks are associated with stuttering, people who don't stutter sometimes use these behaviors and people who stutter use other dysfluencies besides these. The presence of these behaviors, alone, does not constitute stuttering. The amount of dysfluent behavior can contribute to differentiating between normal dysfluency and stuttering. People who stutter tend to have a greater amount of dysfluency in their speech than people who don't stutter, particularly the intra-morphic behaviors.