Working memory is often described as comprising at least two slave systems for verbal and visuo-spatial information (e.g., Baddeley and Hitch, 1999). Visuo-spatial working memory (VSWM) is often considered as functionally analogous to verbal working memory but identical effects on verbal and visuo-spatial working memory are rarely found, especially a path length effect failed to be assessed. The aim of this thesis is to explore the existence of active rehearsal processes in visuo-spatial working memory. The presence of a Path Length Effect, defined as an improved recall of location when the sum of inter-targets lengths is short, is present in all the experiments. Path length effect could be interpreted as the existence of an active internal rehearsal process at least partially linked to overt responding. Comparisons between experiments also reveal another effect, the Reference Space Effect compatible avec the hypothesis of two distinct processes in VSWM. Conclusion also discuss an alternative hypothesis in which Reference Space Effect and Path length effect are underlined bas the same processes but data suggest that the hypothesis of separate processes is more convincing.
