<p>Distribution of the Pearson’s correlation coefficients between heart rate profiles during EST1 and EST2 for all individuals (n = 821). First, second and third quartiles correspond to cases A, B and C, respectively. The HR profiles corresponding to these values are shown in panels (A)-(C). Each panel is composed of two sub-panels, one on the left showing x<sub>HR</sub>(t) against time and using the same vertical axis for EST1 and EST2, and another one on the right showing x<sub>HR</sub>(t) against EST phase (0 and 1 correspond to the beginning and end of each EST) and with different vertical scales adjusted to span the HR range of x<sub>HR</sub>(t) during EST1 and EST2.</p
