Figure 4.
Post-illumination changes in sleep propensity (sleep latency−1) measured during darkness after exposure to red, green and blue light (Experiment 3). The bars represent sleep propensity after red (PR), green (PG) and blue (PB) light exposure relative to baseline (BL) sleep propensity (i.e. after prior exposure to darkness). The error bars represent the within-subject 95% confidence interval. Asterisk indicates within-subject differences between the post-light trials and the post-dark trials (*p < 0.05).