Eh… I forgot what I was going to say. How do memory and lexical access affect speech fluency?

Abstract

Many studies revolving around speech research have questioned what may cause disfluency in typical speakers by considering aspects such as gender, age and personality factors. However, the results established between these groups are inconsistent and therefore, unreliable. This study provides evidence to suggest that the reason it is so difficult to find reliable trends in the frequency and types of disfluencies between groups, is because so much variation can be identified within groups. This study attempts to fill a gap in our understanding about disfluencies in typical speakers. This study investigates the variation in the disfluencies observed in spontaneous speech (average frequency and type of disfluencies observed across 3 running speech tasks) and how they correlate with working memory and rate of lexical access variation. The results were examined using SPSS to establish any correlations. A digit span task was employed to establish working memory abilities. It was found that working memory abilities correlate negatively with the frequency of disfluencies found in spontaneous speech. Working memory scores also showed a strong negative correlation with the frequency of repair disfluencies. An attempt to explain this correlation is made during this study in relation to the ability to self-monitor in speech (Jacquemot and Scott 2006). To determine the rate of lexical access 3 verbal fluency tasks were used: 2 semantic and 1 letter fluency task. These results highlight a negative correlation between lexical access and the frequency of disfluencies in spontaneous speech. Another significant negative correlation is found between lexical access and hesitations: if lexical access is slow, hesitations are used to allow extra time to retrieve words. This study highlights that lexical access and working memory abilities contribute to the variation in disfluencies found in spontaneous speech and attempt is made to explain why this is the case.