Figure 2From: Daily rhythms of the sleep-wake cycleTimes of sleep and wake (top, separated by the double vertical lines). The C component is represented by two curves (Upper C and Lower C). Sleep pressure increases exponentially in the wake phase (Process S, dotted line) and decreases at a faster exponential rate in the sleep phase (S', dashed line). For more details, see text. (Based on [21]).Back to article page