E-learning platforms have emerged and played a crucial role in knowledge sharing and dissemination of information at large. However, an optimal knowledge acquisition in e-learning platforms is still a challenge due to poor interactive learning environment. To address that challenge, in this study a correlation between visual spatial attention, learners' motivation states and long-term memory during learning process has been investigated through learners' cognition detection based on their metacognitive experiences by using electroencephalogram (EEG). The obtained results show strong correlation between visual spatial attention, motivation states and long-term memory. Based on the obtained results, this paper proposes brain-computer interface based approach to assist adaptation of learners' motivation states in e-learning platforms. The study paves a way for the aptitude-treatment interaction monitoring and involvement of deaf individuals in e-learning platforms.