The cortisol awakening response and the late positive potentials evoked by unpleasant emotional pictures in healthy adults

Figures & data

Table 1. Descriptive statistics for all relevant variables.

	Day 1		Day 2
	Mean	SD	Mean	SD
Cortisol 1 (0 min) (nmol/L)	17.22	5.41	15.72	5.30
Cortisol 2 (30 min) (nmol/L)	20.95	6.97	21.50	6.78
Cortisol 3 (45 min) (nmol/L)	20.28	6.49	19.22	6.63
Sleep quality	6.38	2.01	7.13	1.64
Pre-task cortisol (nmol/L)	9.11	3.44
Average CAR	5.16	4.88
Average Log CAR	0.11	0.08
The mean amplitude of ΔLPP (μV)	2.52	1.56

Figure 1. Grand-averaged waveforms for unpleasant, neutral pictures and the unpleasant minus neutral difference wave at Pz.

Figure 2. Scalp distributions of neutral (A), unpleasant (B), and difference (C) LPP waveforms (300–1000ms).

Figure 3. Scatter plot of the bivariate correlation between CAR and the ΔLPP mean amplitude (n = 46).

Table 2. Regression analysis (with covariates) with CAR as the predictor and ΔLPP mean amplitude as the dependent variable.

	Predictors	Β	t	p	R^2	ΔR^2
Step 1	Sex	0.000	0.000	1.000	0.011
	Sleep quality	0.071	0.450	0.655
	Pre-task cortisol	−0.082	−0.527	0.601
Step 2	Sex	0.122	0.828	0.413	0.207	0.196
	Sleep quality	0.019	0.136	0.893
	Pre-task cortisol	−0.063	−0.445	0.659
	CAR	−0.464	−3.144	0.003

Values in bold represent significant.