Table 1.

Melatonin suppression and phase delays in different light conditions

	1 lux prior light history						90 lux prior light history
	1 lux LE		90 lux LE		Δ by LE		1 lux LE		90 lux LE		Δ by LE		Δ by prior light history
Subject	Supp	Shift	Supp	Shift	ΔSupp	ΔShift	Supp	Shift	Supp	Shift	ΔSupp	ΔShift	ΔSupp	Δ Shift
23D6	14	0.01	87	1.28	73	1.26	29	−0.61	87	0.63	58	1.24	15	0.03
25A7	1	0.11	83	0.70	82	0.59	44	0.40	93	1.89	49	1.49	33	−0.91
25E4	−17	0.04	88	1.73	105	1.69	1	0.05	17	0.78	15	0.74	90	0.96
25H7	−3	0.57	92	2.51	95	1.94	22	0.88	89	2.00	67	1.11	28	0.82
25M9	−10	0.48	90	2.23	100	1.75	2	0.81	66	1.93	64	1.12	36	0.64
25Q5	−13	−0.26	74	1.12	88	1.38	3	−0.13	67	1.40	64	1.53	23	−0.15
25R7	1	−0.43	60	1.22	59	1.65	2	−0.04	15	1.41	13	1.45	46	0.20
2602	−13	0.77	88	2.38	101	1.61	4	0.66	74	1.58	70	0.92	31	0.69
2690	−4	0.02	78	2.07	81	2.05	0	0.70	16	1.51	16	0.81	65	1.24
26C2	17	−0.58	86	1.80	70	2.39	24	0.27	49	1.43	25	1.16	45	1.23
26E3	−17	−0.08	78	1.73	95	1.81	14	0.31	82	1.12	68	0.80	27	1.01
26F9	−1	0.45	94	2.45	95	2.01	1	0.99	90	0.72	89	−0.27	6	2.27
26P9	20	0.28	96	1.91	76	1.63	22	0.14	91	1.38	68	1.23	8	0.40
Mean	−2	0.11	84	1.78	86	1.67	13	0.34	64	1.37	51	1.03	35	0.65
s.d.	12	0.40	10	0.56	14	0.44	14	0.46	30	0.45	25	0.47	23	0.78

Melatonin suppression (Supp; in %) and phase shift (Shift; in hours) under 4 different light conditions: 1 lux prior light history and 1 lux LE, 1 lux prior light history and 90 lux LE, 90 lux prior light history and 1 lux LE, and 90 lux prior light history and 90 lux LE. The differences (Δ) for both melatonin suppression and phase shift are shown as a function of LE (1 lux vs. 90 lux) and as a function of prior light history (1 lux vs. 90 lux). Group mean and standard deviation (s.d.) values for suppression and phase shifts are shown at the bottom. Positive numbers under Shift indicate phase delays.