Research suggests that “filler” words may be more necessary than we realize:
One study had people sit in front of an array of objects, then grab and manipulate a specific sequence of objects, as directed by a computer voice. Sometimes the computer voice said things like, “Move the box.” Other times it added a filler word, saying, “Move the, uh, box.” The task wasn’t complex, and people had no trouble following the directions. Still, they were quicker to follow directions that involved objects they hadn’t yet manipulated when their instructions included an “uh.” To listeners, “uh” indicates that something new, which requires more mental processing on the part of the speaker, is about to be introduced. This helped the study participants put themselves in the right mindset of choosing from the as-yet unfamiliar objects.
So even a word that’s no more than a grunt is helpful. Which is good, because all languages have verbal filler. American Sigh Language has a sign for “um,” and most languages have some monosyllable that has no meaning but indicates a pause.
The Dish 