Abstract : Understanding how we solve problems, and more broadly how we work, is fundamental in learning. Therefore, the development and transmission of metacognition and metacognitive abilities are central in this area. In this thesis, we investigate the connections existing between metacognition, consciousness, awareness, attention and subjectivity. The interweaving of these dimensions suggests that it is possible to use techniques training awareness and attention in order to develop metacognition. We worked with young adults in a longitudinal study and showed that it is indeed possible to use these attentional practices (relaxation and meditation techniques) to significantly develop metacognition (metacognitive knowledge and accuracy). Thus, a new kind of metacognitive remediation based on attentional practices is considered. Through these techniques, the subject is back to the center of metacognition, on a theoretical and practical level. We emphasized this very notion throughout this thesis in order to get a better understanding of how metacognition works, so as to underline the fact that this concept has deep connections with other dimensions of human cognition, that need to be considered when studying metacognition.