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12019-10-13T15:03:31-07:00Emilie Rinaldi1c99118b882203af66a4b67e96fac3e31f84d7c2349542plain2019-10-13T19:02:29-07:00Emilie Rinaldi1c99118b882203af66a4b67e96fac3e31f84d7c2 For an adult, a normal postural sway has an average amplitude of 2.7cm (Wann et al, 1998). Both proprioception and the vestibular system play a role in triggering rapid postural adjustments, however vision may contribute to slow postural adjustments (Wann et al., 1998). The role of vision in postural stability can be observed when standing in an awkward position and closing one’s eyes. Body sway is attenuated by 50 % when the eyes are open compared to when they are closed (Wann et al., 1998). It is a reasonable to hypothesize that some children suffering form DCD may have issues in mapping between vision and proprioception in postural control (Wann et al., 1998). It has been demonstrated by Stoffregen (1986), that small displacements of a swinging room could induce synchronised postural sway in adults. He also showed that peripheral flow produced the greatest effect. A study done by Wann et al. (1998), recorded head movement of the subjects while standing, in the eyes open condition and the closed eyes condition. This was done to assess postural sway in children with DCD. It was determined that children with DCD exhibited more postural sway compared to their matched controls when eyes were closed (Greuze, 2003). The main focus of the experiment was the ability of participants to maintain equilibrium in the presence of perturbations of the visual environment (Wann et al., 1998). An important factor to consider is that the children with DCD demonstrated significantly higher peak to peak sway when the room was moved. This result suggests that a substantial proportion of the sway response of children with DCD was outside the frequency band of the room motion (Wann et al., 1998). This data displays that children with DCD are more susceptible to general disruption of posture by visual motion (Wann et al., 1998).The results of this study denote that some children suffering from DCD may be behind their matched controls in acquiring skills of integrating visual and non-visual information, as well as relying on vision in the maintenance of posture (Wann et al., 1998).