Test anxiety, categorized as debilitative anxiety, along with sleep quality, have been focal points in numerous academic studies. A significant body of literature in these domains underscores the significance of test anxiety and sleep quality in the EFL educational setting. Furthermore, a research gap has been identified, pinpointing the necessity for further exploration into the correlation between sleep quality and test anxiety. The primary objective of the present study is to delve into two specific research areas within a singular investigation. Firstly, the study endeavors to examine the potential relationship between test anxiety and varying proficiency levels among Iranian EFL learners. Secondly, the researcher seeks to predict the influence of sleep quality on the test anxiety levels of Iranian EFL learners using Brain Mapping. This methodological choice stems from the fact that a majority of prior studies have relied solely on questionnaires and diaries to explore the relationship between sleep quality and test anxiety, which are inherently subjective self-reporting tools. In contrast, this study intends to investigate any possible connections through Brain Mapping, an experimental tool aimed at mitigating the limitations of self-reporting. Ultimately, at the conclusion of the research, the researcher will elucidate the beliefs of Iranian EFL learners regarding the impact of sleep quality on test anxiety.