Work on establishing tiny malagasy primate as a new systems neuroscience animal model. Transferring experimental techniques from rodents to primates, developing behavioural paradigms, establishing surgeries and exploring capabilities of the mouse lemur led me to be involved in several research projects. As for the topic of my thesis, I chose to focus on spatial navigation and orientation. Self-perception in space is a long-debated topic and has been scientifically studied since the invention of analytic philosophy in the late 19th century. Orientation and navigation in space are among the main features characterizing animal behavior. Indeed, most animals spend a substantial part of their awake time trying to reach a specific location. Changing location increases the chance of finding mates, food, seeking better environmental conditions, or escaping predators and within-species competition. How does an organism know where it is going? How will it come back? And why is it lost now and then? These questions have been extensively studied in various animal species and have led to fundamental insights into the computational processes that underlie spatial navigation. This research project attempts to tackle a new aspect of navigation, namely the third dimension of space. Exploring arboreal environments has probably been a main driver behind primate evolution, thus understanding how three dimensional space is represented in the primate brain seems to be a pertinent question. At the heart of this study is a small and arboreal mammal, which has retained many of the hallmarks of early primates: the gray mouse lemur (Microcebus murinus). This malagasy prosimian weighs only 60gr and thus facilitates the holding and handling compared to other, larger primates. In addition, it allows the direct transfer of many experimental tools initially designed for rodents.