Beyond hearing: investigating the combined impact of working memory and metacognitive training on EFL listening comprehension and working memory capacity

Although metacognitive intervention (MI) and working memory capacity (WMC) are both known to support L2 listening, previous research has largely examined cognitive capacity and metacognitive regulation as separate explanatory systems. Guided by an integrative resource availability–resource regulation framework, the present study investigated the comparative and combined effects of working memory training integrated instruction (WMT), metacognitive intervention (MI), and the combined condition (WMT + MI) on the listening comprehension (LC) and WMC of Iranian intermediate EFL learners. A randomized pretest–posttest controlled experimental design using convenience sampling for selection was employed. Following eligibility screening, 103 all-male learners (aged 15–18) from a private language institute in Babol were randomly assigned to three experimental groups and a control group (WMT = 23, MI = 26, WMT + MI = 26, CG = 28). After attrition-related exclusion ( n = 20), 83 participants completed all phases (WMT = 19, MI = 21, WMT + MI = 20, CG = 23). Result revealed that while all active treatments led to improvements, WMT+MI and MI were particularly effective in enhancing LC, whereas WMT+MI and WMT comparably enhanced WMC, with no statistically significant difference between them. In both cases, the WMT+MI condition displayed a descriptively higher adjusted mean that did not reach statistical significance over MI (for LC) or WMT (for WMC) alone. These findings suggest that addressing both resource availability and resource regulation offers a theoretically promising route for L2 listening pedagogy, though the additive benefits of combined instruction warrant further empirical investigation.