Research has suggested that long spacing (i.e., temporal intervals) within a training session facilitates second language vocabulary learning. Studies, however, have been limited to treatment that involved sessions for only initial learning but not subsequent relearning. Furthermore, most studies have investigated only the benefits of spacing…

Research suggests that testing (or retrieval) has the potential to enhance second language (L2) vocabulary learning. Given the positive effects of testing, how L2 vocabulary learning from tests can be optimized is an important question. One way to increase the benefits of testing may be to use cumulative tests, where not only recently studied but…

In the coda chapter of the special issue on second language (L2) practice and cognitive psychology, we proposed a theoretical framework for optimizing and researching L2 practice (Suzuki, Nakata, & DeKeyser, 2019). Rogers and Leow's commentary (2020) raised three potential issues regarding this framework, and the present response article aims…

Although research shows that repetition increases second language vocabulary learning, only several studies have examined the long-term effects of increasing retrieval frequency in one learning session. With this in mind, the present study examined the effects of within-session repeated retrieval on vocabulary learning. The study is original in…

Although researchers argue that studying semantically related words simultaneously (semantic clustering) inhibits vocabulary acquisition, recent studies have yielded inconsistent results. This study examined the effects of semantic clustering while addressing the limitations of previous studies (e.g., confounding of semantic relatedness with other…

Studies examining decontextualized associative vocabulary learning have shown that long spacing between encounters with an item facilitates learning more than short or no spacing, a phenomenon known as distributed practice effect. However, the effect of spacing on learning words in context is less researched and the results, so far, are…

Although expanding spacing is often regarded as the most effective practice schedule, studies comparing equal and expanding spacing have yielded mixed results. The present study set out to examine whether the amount of spacing and the retention interval may influence the effects of expanding and equal spacing on second language (L2) vocabulary…

Feedback, or information given to learners regarding their performance, is found to facilitate second language (L2) learning. Research also suggests that the timing of feedback (whether it is provided immediately or after a delay) may affect learning. The purpose of the present study was to identify the optimal feedback timing for L2 vocabulary…

This study investigates the effects of cognacy on vocabulary learning. The research expands on earlier designs by measuring learning of English-Japanese cognates with both decontextualized and contextualized tests, scoring responses at two levels of sensitivity, and examining learning in a more ecologically valid setting. The results indicated…

The present study aims to conduct a comprehensive investigation of flashcard software for learning vocabulary in a second language. Nine flashcard programs were analysed using 17 criteria derived from previous studies on flashcard learning as well as paired-associate learning. Results suggest that in general, most programs have been developed in a…

The spacing effect is known to be one of the most robust phenomena in experimental psychology, and many attempts have been made to realize effective spaced learning for L2 vocabulary learning. This study compares vocabulary learning with word lists, word cards, and computers in order to identify which material leads to the most superior spaced…