Fig. 1.

Average time profile of the center of pressure (CoP) oscillation around the time of visual shift. a, b The mean A-P CoP oscillation of one subject during the EO–EC and EC–EO trials. Time flows from left to right starting with EO (a) and with EC (b), until t = 10 s, at which visual condition changes. c, e show the probability of rejecting the zero hypothesis regarding the mean difference between the two oscillation traces after the visual condition change. The EO trace (c) becomes significantly different from the EC trace when the probability drops below the line at y = 1.67; vice versa for e. The corresponding intervals estimate the latency of the stabilizing effect of addition (a, c) or withdrawal of vision (b, e). The CoP traces are fitted with an exponential curve, the time constant of which is calculated for estimating the time to recovery steady state