Cognitive Effort in Dutch Word Reading

Purpose: Although the concepts of effort and effortlessness have been around since the dawn of modern psychology, their definition and operationalization in the reading field has been neglected. We previously reported a pupillometric investigation in which we initially observed a greater degree of cognitive effort for reading unfamiliar letter strings compared to familiar words, in both oral and silent modes among Hebrew-speaking skilled adults and developing readers. The present study aimed to provide an initial step toward establishing universals and specifics regarding the issue of cognitive effort in word reading by focusing on a typical European alphabetic writing system–Dutch. Method: Twenty-four Dutch-speaking university students participated in two pupillometric experiments comparing cognitive effort in reading familiar and unfamiliar letter strings (words and pseudowords). Experiment 1 included monosyllabic stimuli varying from 3 to 5 letters: Experiment 2 contained bisyllabic stimuli varying from 6 to 8 letters. Results: In both experiments, readers showed more effort when reading unfamiliar (pseudo)words. Length effects and familiarity-by-length interactions also suggested greater reliance on serial, letter-by-letter processing. Bayesian analysis revealed temporal differences between the effects, such that the familiarity effect preceded the length effect. Conclusions: The findings suggest that familiarity-dependent differences in cognitive effort in word reading may be a universal property across writing systems. However, even short familiar words required some degree of cognitive effort suggesting that, in line with prior pupillometric studies, the use of terms such as “effortless” and “effortlessness” in current definitions of word reading fluency are inaccurate. In addition, pupillometry, unlike reaction times, appears to capture the time course over which effects occur.