Neural correlates of the processing of unfilled and filled pauses

Spontaneously produced Unfilled Pauses (UPs) and Filled Pauses (FPs) were played to subjects in an fMRI experiment. While both stimuli resulted in increased activity in the Primary Auditory Cortex, FPs, unlike UPs, also elicited modulation in the Supplementary Motor Area, Brodmann Area 6. This observation provides neurocognitive confirmation of the oft-reported difference between FPs and other kinds of speech disfluency and also could provide a partial explanation for the previously reported beneficial effect of FPs on reaction times in speech perception. The results are discussed in the light of the suggested role of FPs as floor-holding devices in human polylogs.