The Importance of Managing Interference for Second Language Reading Ability: An Individual Differences Investigation

Abstract

Research on individual differences in second language (L2) reading ability has primarily focused on factors known to contribute to first language (L1) reading ability, with little consideration of factors mediating interference between languages. In an exploratory analysis, we compared the degree to which the linguistic interference that readers experience predicted reading ability in L1 and L2. Based on current psycholinguistic models, we also investigated whether the relation is mediated by working memory capacity. A series of regression analyses were performed to investigate these relations in 83 monolinguals, 50 L1 English-speaking bilinguals, and 127 L2 English-speaking bilinguals. Results revealed that the amount of linguistic interference experienced significantly predicted reading ability in L2 but not in L1 or for monolinguals. Further, the relation was not mediated by individual differences in working memory capacity. These results illustrate the need for consideration of cross-linguistic factors for models of L2 reading ability in particular.

Acknowledgments

We thank Theresa Becker and Justin Abernethy for their comments on this manuscript.

FUNDING

This research was supported by start-up research funds provided by the Institute for Learning & Brain Sciences.

Notes

¹ Although participants’ language profiles were based on self-reported measures, the internal and criterion-based validity of the Language Experience and Proficiency Questionnaire have been established (Marian et al., 2007), suggesting these self-reported measures are reliable indicators of language ability.

² A subset of participants also completed a computerized Reading Span task (van den Noort, Bosch, Haverkort, & Hugdahl, 2008). However, because previous research suggests that language proficiency interacts with performance on this working memory task (Service, Simola, Metsänheimo, & Maury, 2002), to avoid a potential confound with English language proficiency, this task was not included our analyses.

³ All tasks were administered in a pseudo-random order, so it is unlikely there were systematic effects on the subset of tasks analyzed here.

⁴ Separate analyses conducted on measures of Nelson-Denny Vocabulary percentile scores and Nelson-Denny Comprehension percentile scores revealed the same pattern of results for our critical variable of interest, L2 reading ability. For the first analysis, measures of working memory and linguistic interference experienced were entered as predictor variables, with Nelson-Denny Vocabulary percentiles scores alone entered as the criterion variable. The model was a significant predictor of L2 reading ability (R² = .087, F(2, 85) = 3.95, p = .023), with only linguistic interference uniquely predicting L2 Vocabulary (t = 2.60, p = .011). For the second analysis, measures of working memory and linguistic interference were entered as predictor variables, with Nelson-Denny Comprehension percentiles scores alone entered as the criterion variable. Consistent with the previous analysis, the model significantly predicted reading ability (R² = .126, F(2, 50) = 3.46, p = .039), with linguistic interference being the only independent factor significantly predicting L2 Comprehension (t = 2.05, p = .046).