Vocabulary acquisition is crucial for second language proficiency, impacting all four language skills (listening, speaking, reading, and writing). Nation's (2001) model of vocabulary knowledge, encompassing form, meaning, and use (each with receptive and productive aspects), guides this study. While technology-enhanced language learning has been widely explored (using multimedia annotations, video games, mobile apps, and virtual reality), the efficacy of infographics in second language vocabulary acquisition remains under-researched. Infographics, defined as visual encodings of visual and textual media, offer a promising approach to enhancing vocabulary learning by improving information visualization, organization, and processing. This study investigates the impact of infographics on L2 vocabulary gain among Arab EFL learners over a 10-week period, assessing vocabulary knowledge according to Nation's model and exploring learners' perceptions of using infographics.

Several studies have investigated the effectiveness of technology in second language vocabulary acquisition, demonstrating the benefits of multimedia annotations, video game-based learning, mobile-assisted language learning, and virtual reality. These studies highlight the potential of visual aids and technology to enhance learner engagement and long-term memory retention. However, research specifically examining the use of infographics in second language vocabulary learning is limited. Existing studies on infographics in education generally suggest positive effects on learning and retention across various subjects and educational levels, but few studies have focused on their impact on EFL vocabulary acquisition. The current study addresses this gap by investigating the effects of infographics on both receptive and productive vocabulary knowledge in an EFL context, employing a rigorous quasi-experimental design.

This study employed a quasi-experimental two-group pretest-post-test-delayed test design. Forty-one female Arab EFL undergraduate students at Najran University in Saudi Arabia participated, with 21 in the experimental group (infographics-based instruction) and 20 in the control group (traditional instruction). The intervention lasted 10 weeks. Vocabulary knowledge was assessed using three measures based on Nation's (2001) model: two written tests (measuring form-meaning connection and grammatical function knowledge) and an oral interview (measuring productive vocabulary knowledge). A questionnaire gauged learners' perceptions of infographics. The infographics used were created using Piktochart, following a four-phase process involving planning, sketching, design, and production, ensuring alignment with the textbook curriculum. The 30 target vocabulary words were selected from the textbook used in the course and featured in the infographics. Data analysis involved Levene's test for equality of variances, Shapiro-Wilk test for normality, and independent samples t-tests to compare the groups' performance on the vocabulary tests and interview, with statistical significance set at α = 0.05. Descriptive statistics were used to analyze the questionnaire data. Content and face validity of the tests and questionnaire were established through expert review.

The experimental group (infographics-based instruction) significantly outperformed the control group on both written vocabulary tests (word definition and word grammatical measures) at both immediate and delayed post-tests. Specifically, significant differences were found in the immediate post-test for word definition (t(39) = 3.76, p < 0.05, d = 1.05) and word grammatical function (t(39) = 2.66, p < 0.05, d = 0.83). These differences persisted in the delayed post-test (word definition: t(39) = 3.32, p < 0.05, d = 1.03; word grammatical function: t(39) = 2.29, p < 0.05, d = 0.71). The oral interview results also revealed a significant difference between the groups, favoring the experimental group (t(39) = 3.28, p < 0.05, d = 1.02). The questionnaire revealed highly positive perceptions of infographics among the experimental group, with mean scores ranging from 4.05 to 4.71 (on a 5-point Likert scale), indicating that learners found infographics helpful for simplifying complex information, organizing information, improving recall, and enhancing engagement.

The findings strongly support the hypothesis that infographics enhance L2 vocabulary learning and retention. The significant differences between the experimental and control groups across all three assessment measures (written tests and oral interview) demonstrate the effectiveness of infographics in improving both receptive and productive vocabulary knowledge. These results align with previous research highlighting the benefits of multimedia learning and visual aids in education. The positive learner perceptions further corroborate the effectiveness of the infographics-based approach, suggesting that infographics can enhance engagement and motivation. The findings are consistent with the Cognitive Theory of Multimedia Learning (CTML), which posits that learning from words and pictures is more effective than from words alone. The results also align with Skill Acquisition Theory, suggesting that the visual and textual integration in infographics facilitates the automatization of vocabulary knowledge and use.

This study demonstrates the significant benefits of using infographics in teaching L2 vocabulary. The positive impact on both receptive and productive vocabulary knowledge, coupled with highly positive learner perceptions, suggests that infographics can be a valuable tool for EFL instruction. Future research should investigate the effectiveness of infographics across a broader range of vocabulary knowledge aspects (as defined by Nation's model), explore the use of dynamic infographics, and examine the impact on different learner populations and language contexts.

Several limitations should be acknowledged. The sample size was relatively small, potentially limiting the generalizability of the findings. The study focused on female students only, limiting its applicability to male learners. The lack of a pre-existing English language proficiency test may have influenced the results. Finally, the infographics used were static, and future research could explore the use of dynamic infographics. The study also only focused on two of the aspects of vocabulary knowledge proposed by Nation (2001).