In this experimental study, the researcher investigates the effects of complex emotions on cognitive linguistic processing between three distinct EFL (English as a Foreign Language) groups: an experimental group (positive and negative videos) and a control group (no video). The experimental group was exposed to stimuli specifically designed to trigger cognitive and emotional responses. Conversely, the control group was not exposed to any such stimuli. The primary objective of this study is to assess the ability of participants to judge sentences for grammatical correctness. Additionally, participants are tasked with identifying incorrect grammatical structures and pinpointing specific errors. This methodology is rooted in the framework of the control-value theory (CVT). This research aims to contribute to the understanding of how emotional states influence linguistic judgments, which is essential for developing more effective cognitive and educational interventions. By aligning the experimental design with CVT, the researcher hypothesizes that emotional arousal induced by the stimuli may significantly impact the accuracy of grammatical judgment among the participants in the experimental group compared to those in the control group. This study’s implications extend beyond theoretical advancements in cognitive psychology, suggesting practical applications in educational settings and curriculum development focused on enhancing linguistic competencies.