Spatial competences in Prader-Willi syndrome: a radial arm maze study.

The present study was aimed at investigating the spatial abilities in Prader-Willi syndrome (PWS) by using the Radial Arm Maze (RAM) task. We trained PWS individuals with the deletion subtype in two different RAM paradigms that tapped different aspects of spatial memory. To evaluate the extent of spatial deficit in PWS individuals, it seemed interesting to compare their performances with those of individuals with Williams syndrome (WS) in which deficits in spatial abilities have been well described. The two syndromic groups were compared to typically developing (TD) individuals mental-age and gender matched. The findings evidenced the impairment of PWS individuals in solving the RAM task with variable severity depending on the paradigm requests. Since the RAM is a task that allows the acquisition of spatial competences through the movement, we advance that the spatial deficits observed in PWS individuals may be related to the malfunctioning of spatial and motor integrative processing.