Figure 2.

Average melatonin suppression during evening light exposure (11:00 pm–midnight; gray shading) over the three experimental light conditions by puberty group. Average absolute melatonin levels at the three light levels (open circles) relative to unsuppressed baseline levels (black circles) are illustrated for the pre/midpuberty group (left column) and the late/postpuberty group (middle column). Upward arrows indicate significant pairwise comparisons (P < .05). Right column: average suppression for each light level calculated using AUC for the light exposure versus unsuppressed near-dark baseline condition. Asterisks indicate significant differences (P < .05). Error bars indicate standard error.