Fig. 5 |. Measuring functional responses to a blood pressure cuff.

A blood pressure cuff was applied to the upper left arm across the subject’s brachial vein. Baseline flow was measured in a distal metacarpal vein, after which subsequent flow measurements were quantified relative to the mean of this baseline. The cuff was inflated for approximately 10 seconds before release. a, Structural image of the vessel (left) and the vector overlay map for the baseline flow speed (right). b, Vector maps for relative flow measurements at four different time points throughout the experiment: the baseline flow (top left), the flow during cuff inflation (top right), the flow during release (bottom left), and the flow after release (bottom right). c, Discrete-time sequence for relative flow speed changes. The flow speed decreased by approximately 70% during the application of the cuff and increased to approximately 350% upon release before returning to baseline.