Learning a foreign language, particularly English, poses challenges for Rwandan teenagers already introduced to other science subjects like mathematics, physics, and other different courses of action that have occupied their attention, or, on the other hand, disturbs their mind and hinders their learning spirit. This study aimed to investigate how the neurocognitive underpinnings of brain activation methods and integration multisensory work to activate those teenagers’ brain attention to English language learning and develop speaking skills and enable learners to overcome the neurocognitive challenges like lack of motivation, emotions, stress, and anxiety that hinder English language learning and speaking. This study was built around the multisensory theory and brain-based learning theory. Using a semi-longitudinal approach, data was collected from 40 senior two students to explore difficulties in learning English from one school in Nyagatare district. These were selected purposefully from the population of 340 students. A six-week classroom experiment from April 15 to May 23, 2024, gathered both quantitative and qualitative data on how brain activation methods enable English learning speaking. Single-group experiments and observations were used to collect data. In the experiment, the procedure of pretest-treatment-posttest was implemented. SPSS software was used to analyze the data, with results showing improved post-test scores after targeted interventions. In the pre-test, the mean score ranges between 1 and 2.5 with a standard deviation that swings between 0.405 and 0.802 for all questions, while the mean score in the post-test aligns between 3.5 and 5 with a standard deviation that wheels between 0.267 and 0.813, which significantly indicates high scores after the treatment. Therefore, the study highlights the significant impact of brain activation methods accompanied by multisensory integration as the neurocognitive approach to English language learning and speaking. The research suggests that education stakeholders and policymakers should consider this approach for successful English language learning to avoid overloading teenagers’ brains with heavy programs.