Date of Award
Doctor of Philosophy
Veronica J. Dark
When exposed to words presented under perceptually disfluent conditions (e.g., words written in Haettenschweil font), participants have difficulty recognizing the words. Those same words, though, may be better remembered than words presented in standard type font. This counterintuitive finding is referred to as the disfluency effect. Evidence for this disfluency effect, however, has been mixed. Using a recognition memory task, I examined five variables that may contribute to the inconsistent findings: type of judgments of learning (JOLs), encoding instructions, type of disfluency manipulation, encoding duration, and retention interval between study and test. Experiment 1 employed a masking manipulation and examined the influence of type of JOLs (item-by-item JOLs vs. aggregate JOLs) along with encoding instructions (incidental vs. intentional). Experiments 2 and 3 explored the locus of the disfluency effect by examining perceptual disfluency manipulations that tap different loci during word recognition: low-level blurring (pre-lexical) and cursive handwriting (lexical). Experiment 4 examined the role of encoding duration on the disfluency effect. Experiment 5 examined whether list design (blocked vs. mixed) moderates the disfluency effect. Experiment 6 examined whether the benefits of disfluency extend over longer durations (24 hours). Results across the six experiments indicated that the disfluency effect is modulated by testing expectancy, type of disfluency manipulation, and encoding duration. A disfluency effect was observed only under
incidental instructions with a sufficiently long encoding duration. Further, I found that a pre-lexical manipulation (i.e., blurring) did not produce a disfluency effect, but a lexical perceptual disfluency manipulation (i.e., cursive) did. This cursive disfluency effect was moderated by legibility: easy-to-read cursive words tended to be better remembered than hard-to-read cursive words. This finding was bolstered by a meta-analysis. Taken together, these results challenge extant accounts of the disfluency effect. The research comprising this dissertation furthers the theoretical understanding of the disfluency effect as well at its practical implications.
Geller, Jason, "Would disfluency by any other name still be disfluent? Examining the boundary conditions of the disfluency effect" (2017). Graduate Theses and Dissertations. 15520.