The spacing effect refers to the learning benefit that comes from separating repeated study of target items by time or by other items. A prominent proposed explanation for this effect states that repeated exposures that occur closely together may not engage full attentional processing due to residual activation of the previous exposure and also, in an intentional learning context, due to a sense of familiarity that may result in strategic allocation of less study time to an item in massed repetitions. The present study used eye-tracking methodology to investigate the effects of temporal distribution of repeated exposures to novel second language words on attentional processing and learning of these words under intentional learning instructions. Adult native speakers of English read Finnish words embedded in English sentence contexts under massed and spaced conditions. The results showed that (a) massed repeated exposures received less attentional processing than spaced repeated exposures; (b) target words were better remembered in the spaced condition; and (c) attention was a significant mediator of the obtained spacing effect, in line with the predictions of the deficient processing account of the spacing effect. Implications for vocabulary learning are discussed.

Research has produced mixed findings regarding the effects of spacing L2 study. In order to know how this potentially very powerful learning tool can be useful, it is important to understand the cognitive mechanisms that drive the effects in L2 learning and how the operation of these mechanisms may be affected by variables relevant for SLA contexts. In this study, I examine the contribution of the dual mechanism of successful effortful retrieval during study to the lag effect in foreign vocabulary learning from L2-L1 retrieval practice. I additionally investigate the effects of feedback study time on the operation of the two cognitive mechanisms under investigation. Native speakers of English studied Finnish vocabulary during L2-L1 retrieval practice in paired-associate learning while their response latencies and accuracy were recorded. Results suggest that: (a) successful effortful retrieval underlies benefits of spacing L2-L1 retrieval practice: even with immediate feedback study, the benefits of effort are conditional on retrieval success; (b) successful retrieval is more beneficial than unsuccessful retrieval, contrary to proposals where this was not directly tested; and (c) imposing longer study time externally has little benefit, unlike what has been previously found with learner-regulated longer study time. Implications for L2 learning and teaching are discussed.

Statistical significance and averages are two pieces of statistical information that are often presented as evidence in support of researchers’ conclusions and teaching recommendations. In this article, I consider interpretation of this information as research evidence for ELT. In simple terms that will be accessible even to readers without any knowledge of statistics, I explain the basic nature of this information with the aim of elucidating what it can and cannot tell us about ELT findings and the implications for our teaching. I discuss what additional information crucially must be considered for adequate interpretation, and specifically how interpretation depends on this information. I urge producers of ELT research to present and interpret this important information and consumers of ELT research to consider it in assessing the implications of ELT findings for their teaching.