On disfluencies

Your Speech Is Packed With Misunderstood, Unconscious Messages, by Julie Sedivy:

Since disfluencies show that a speaker is thinking carefully about what she is about to say, they provide useful information to listeners, cueing them to focus attention on upcoming content that’s likely to be meaty. […]


Experiments with ums or uhs spliced in or out of speech show that when words are preceded by disfluencies, listeners recognize them faster and remember them more accurately. In some cases, disfluencies allow listeners to make useful predictions about what they’re about to hear. In one study, for example, listeners correctly inferred that speakers’ stumbles meant that they were describing complicated conglomerations of shapes rather than to simple single shapes.


Disfluencies can also improve our comprehension of longer pieces of content. Psychologists Scott Fraundorf and Duane Watson tinkered with recordings of a speaker’s retellings of passages from Alice’s Adventures in Wonderland and compared how well listeners remembered versions that were purged of all disfluencies as opposed to ones that contained an average number of ums and uhs (about two instances out of every 100 words). They found that hearers remembered plot points better after listening to the disfluent versions, with enhanced memory apparent even for plot points that weren’t preceded by a disfluency. Stripping a speech of ums and uhs, as Toastmasters are intent on doing, appears to be doing listeners no favors.