INVESTIGATING THE EFFECTS OF FILLERS IN SPONTANEOUS SPEECH ON FLUENCY PERCEPTION

Fillers have conventionally been regarded as speech disfluencies, reflecting uncertainty, anxiety, or lack of planning on the part of the speaker. However, emerging research has suggested that they may also signal cognitive effort and serve communicative functions. This exploratory study examined how different types and positions of fillers influence perceived fluency in spontaneous speech, focusing on three groups of raters: Vietnamese linguistics students, Vietnamese non-linguistics students, and native English speakers. Fifteen participants (five per group) completed a listening rating task, assessing fluency in speech samples containing silent pauses, unlexicalized filled pauses, and lexicalized filled pauses in varied positions. Given the small sample size, the analysis aimed to identify preliminary trends rather than produce generalizable conclusions. Results indicated that both the forms and positions of fillers affected fluency perceptions across L1 and L2 rater groups, with the form of the filler exerting a more pronounced effect than its position. These findings suggest a greater need for linguistics students, in particular, to be aware of the specific fillers they use in speech. Future research should expand the participant pool to increase statistical power and explore in greater depth how different listener groups interpret fillers in spontaneous speech.