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In 1970, Japanese researcher Masahiro Mori published a seminal paper where he hypothesized that robots that appear human-like but are still distinguishable from being human would not attract people towards them, but instead cause an uncanny sensation. This phenomenon, known as the uncanny valley effect, has been widely studied within the social robotics community, and a multitude of experiments have since been conducted supporting Mori's hypothesis. The specifics of a robot's appearance and behavior leading to such an uncanny sensation, however, remain an open research question and require further study. These gaps in the causal relationship between uncanny feelings and a robot's design have lead uncanniness being increasingly used to explain any lack of enthusiasm towards robots, both in the scientific community and the general public. It is then often implicitly assumed that uncanny feelings towards a robot have damaging consequences for long-term human-robot interaction. Most empirical studies on the subject, however, focus on still images or short video clips of robots and participants are only exposed to these stimuli for small frames of time. The current literature on the uncanny valley does not thus allow a conclusion to be drawn about the persistence of uncanny feelings. This thesis addresses this gap in the body of knowledge by implementing interactive scenarios and performing a series of empirical investigations to study the development of people's uncanny feelings towards social robots over the course of one or several such interactive encounters with them. The findings suggest that novelty plays an important role in the feeling of uncanniness: Merely interacting with a robot for a brief period and thus giving human observers access to the robot's full behavioral stream lowers their rating of uncanny feelings towards the robot as compared to how they perceive it at first sight. Furthermore, repeated interactions with a robot can further lower uncanny impressions. These results contribute to the field of human-robot interaction, as they posit that increased exposure may result in limited feelings of uncanniness. This, in turn, potentially reduces the impact of uncanny feelings on long-term interactive encounters with robots. Instead of focusing on reducing the elicitation of uncanny first impressions, it may thus be more sustainable to further study how interactions can help people efficiently get to know a robot and overcome their initial reluctance towards it.