Still from Movie 5, showing the region observed by AIA 171 Å that is displayed in Fig. 1 in the main text. The coronal structures labelled A, B, 1, 2 and 3 are all visible in the movie. Note the visible motion in feature 3, in which the analysis finds relatively large velocity amplitude (> 5 km s-1) transverse displacements. This is compared with the other structures, where our analysis revealed only small velocity amplitudes.