OTTAWA - Canadian scientists have discovered that the human brain undergoes a seasonal depletion of the “happy hormone,” a finding they believe explains why moods get darker as days get shorter. State-of-the-art brain scans taken at different times of the year reveal that in the autumn and winter, people have significantly higher levels of a protein that removes serotonin from the brain than they do in spring and summer. Serotonin is a key brain chemical that manipulates mood, energy and sleep. The finding, the first of its kind in the living human brain, “has the potential to explain seasonal changes in normal and pathological behaviours,” the researchers report in the journal Archives of General Psychiatry.

A staggering 25% of people have reported disorders of sleep. Sleep disorders have an enormous impact upon quality of life. The medical, economic and personal toll of sleep disorders is huge. From industrial acidents caused by people working shifts and not being alert to car accidents caused by falling asleep at the wheel of a car or lorry. From the elderly engaged in nightime wandering to the child failing at school due to lack of sleep.