Adult age differences in wrap-up during sentence comprehension: Evidence from ex-gaussian distributional analyses of reading time

Brennan R. Payne, Elizabeth A.L. Stine-Morrow

Research output: Contribution to journalArticle


We report a secondary data analysis investigating age differences in the effects of clause and sentence wrap-up on reading time distributions during sentence comprehension. Residual word-by-word selfpaced reading times were fit to the ex-Gaussian distribution to examine age differences in the effects of clause and sentence wrap-up on both the location and shape of participants' reaction time (RT) distributions. The ex-Gaussian distribution showed good fit to the data in both younger and older adults. Sentence wrap-up increased the central tendency, the variability, and the tail of the distribution, and these effects were exaggerated among the old. In contrast, clause wrap-up influenced the tail of the distribution only, and did so differentially for older adults. Effects were confirmed via nonparametric vincentile plots. Individual differences in visual acuity, working memory, speed of processing, and verbal ability were differentially related to ex-Gaussian parameters reflecting wrap-up effects on underlying reading time distributions. These findings argue against simple pause mechanisms to explain end-of-clause and end-of-sentence reading time patterns; rather, the findings are consistent with a cognitively effortful view of wrap-up and suggest that age and individual differences in attentional allocation to semantic integration during reading, as revealed by RT distribution analyses, play an important role in sentence understanding.

Original languageEnglish (US)
Pages (from-to)213-228
Number of pages16
JournalPsychology and aging
Issue number2
StatePublished - Jun 2014



  • Aging
  • Ex-Gaussian
  • Individual differences
  • RT distributional analysis
  • Sentence processing
  • Working memory
  • Wrap-up

ASJC Scopus subject areas

  • Aging
  • Geriatrics and Gerontology
  • Social Psychology

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