The present study is based on the premise that some sort of normalisation strategy is applied to objects presented at unfamiliar orientations. The strategy employed appears to be that of mental rotation (Jolicoeur, 1985), especially in mono-oriented stimuli (Leek, 1998). The Dorsal stream is suggested to deal
with more spatial and motor aspects of vision and it is possible that the inferior parietal lobule is responsible for binding these two sources of information as suggested by Milner (1995). The purpose of these experiments was to further investigate the significance of visuo-spatial normalisation resources in object
recognition, particularly mental rotation. It appears that visuo-spatial working memory may deal with visual and spatial information separately, and that the spatial aspect of memory is associated with movement control, especially motor planning (Smyth and Pendleton, 1989). It was decided that the dual
tasks employed in these experiments should involve primarily a spatial dual task, and possibly a motor task. A word-picture verification task was adapted from Leek (1998) and various dual tasks were tested concurrently. In each case the spatial dual task had a greater effect on reaction times than the nonspatial
dual task, and a motor spatial dual task appeared to have a greater effect than a spatial task. Two experiments tested whether mental rotation resources could be primed by a mental rotation task, previous experiments have shown that it is possible to prime a certain view of an object (Lawson and Humphreys, 1996), or to prompt the use of certain resources based on the task used (Takano, 1989). The results of the present experiment, however, suggest that resources can be primed by a previous task and that this improves performance at mental rotation.