The cortisol awakening response (CAR) and post awakening melatonin secretion

We are exploring the relationship between the CAR and melatonin secretion (measured in saliva) in the first 45 minutes post awakening. Melatonin and cortisol secretion are closely related and the role of melatonin in predicting psychological indices, known to be associated with the CAR, has not yet been explored. For example, as melatonin is associated with somnolence we predict melatonin secretion may be associated with indices of fatigue. Data collection is currently underway.