Effects of aging, word frequency, and text stimulus quality on reading across the adult lifespan: Evidence from eye movements.

Abstract

Reductions in stimulus quality may disrupt the reading performance of older adults more when compared with young adults because of sensory declines that begin early in middle age. However, few studies have investigated adult age differences in the effects of stimulus quality on reading, and none have examined how this affects lexical processing and eye movement control. Accordingly, we report two experiments that examine the effects of reduced stimulus quality on the eye movements of young (18–24 years), middle-aged (41–51 years), and older (65+ years) adult readers. In Experiment 1, participants read sentences that contained a high- or low-frequency critical word and that were presented normally or with contrast reduced so that words appeared faint. Experiment 2 further investigated effects of reduced stimulus quality using a gaze-contingent technique to present upcoming text normally or with contrast reduced. Typical patterns of age-related reading difficulty (e.g., slower reading, more regressions) were observed in both experiments. In addition, eye movements were disrupted more for older than younger adults when all text (Experiment 1) or just upcoming text (Experiment 2) appeared faint. Moreover, there was an interaction between stimulus quality and word frequency (Experiment 1), such that readers fixated faint low-frequency words for disproportionately longer. Crucially, this effect was similar across all age groups. Thus, although older readers suffer more from reduced stimulus quality, this additional difficulty primarily affects their visual processing of text. These findings have important implications for understanding the role of stimulus quality on reading behavior across the lifespan.

Effects of adult aging on letter position coding in reading: Evidence from eye movements.

“…In Experiment 2 older adults displayed standard adult age differences in reading, with older adults producing longer sentence reading times than young adults in line with Experiment 1 and previous research (Kliegl et al, 2004; McGowan et al, 2014, 2015; Paterson et al, 2013a, 2013b; Rayner, Reichle, et al, 2006; Stine-Morrow et al, 2010; Warrington et al, 2018). 4 Both age groups were sensitive to transpositions in all positions within a word, as reading times were longer for each of the transposed letter conditions compared to normally presented text.…”

Adult Age Differences in Effects of Text Spacing on Eye Movements During Reading

“…The present study provides valuable evidence concerning effects of aging and text spacing on eye movements during reading. First, the findings showed clear patterns of age-related reading difficulty, resonant with findings from previous research (e.g., Kliegl et al, 2004; Rayner et al, 2006, 2009, 2011, 2013; Stine-Morrow et al, 2010; Paterson et al, 2013a,b,c; Jordan et al, 2014; McGowan et al, 2014, 2015; Whitford and Titone, 2016, 2017; Warrington et al, 2018). As in this previous research, the older adults read more slowly and made more and longer fixations and more regressions than young adults.…”

“…Considerable evidence shows that older adults (aged 65+ years) experience greater difficulty reading compared to young adults (aged 18–30 years), even when their visual and cognitive abilities appear normal (see Gordon et al, 2015). This is especially clear from studies of eye movements during reading, which consistently show that older adults read more slowly than young adults, by making more and longer fixations, and more backward eye movements, despite achieving normal comprehension (e.g., Kliegl et al, 2004; Rayner et al, 2006, 2009, 2011, 2013; Stine-Morrow et al, 2010; Paterson et al, 2013a,b,c; Jordan et al, 2014; McGowan et al, 2014, 2015; see also Whitford and Titone, 2016, 2017; Zang et al, 2016; Choi et al, 2017; Li et al, 2018; Wang et al, 2018a,b; Warrington et al, 2018). Some eye movement studies have also investigated adult age differences in the word frequency effect, which is the reading time cost for words that have a lower rather than higher frequency of written usage (e.g., Inhoff and Rayner, 1986; Rayner and Duffy, 1986; Rayner et al, 1996; White, 2008).…”

Effects of Normative Aging on Eye Movements during Reading

“…Studies comparing the eye movements of older adult readers (typically 60+ years) and young adult controls (18-30 years) show that older adults make more and, on average, longer fixations and more regressions [64,80,[82][83][84][95][96][97][98][99][100]. These findings suggest the older adults read more slowly and experience greater reading difficulty.…”