(a)-(d): Results from the TTSR data-set. (e)-(h) Results from the TTCR data-set. Circles and bars represent the median and the interquartile range of the temporal median of indices. In TTSR, on the left, temporal median are estimated in early supine (TES), head-up tilt (THT) and later supine (TLS) positions. In TTCR, on the right, temporal median are estimated in supine (TES) and head-up tilt (THT) positions. Dashed lines in (a) and (e) represent the mean value of the threshold function used to assess the significance of coherence estimates.