FIGURE 4.

HRV moderates the relationship between sAA and cortisol reactivity slope. Plotting effects from the piecewise growth curve model examining cortisol trajectory before the knot point. Panel depicts individuals with HRV during the TSST tasks (story and math) 1 standard deviation (SD) below the mean. Y axis is the cortisol concentration. X axis is the time before peak (representing reactivity time or growth prior to the knot point). Line colors depict mean sAA ± 1 SD used only for visualization purposes (continuous variable in GCM). Shading around lines represent 90% confidence interval of the slope of the line. In those with lower HRV, cortisol reactivity (x = time, y = cortisol, slope = reactivity) varied with levels of sAA: Higher sAA related to steeper cortisol increases