Rates of depression and people reporting depression symptoms have increased in the past few decades, and there are almost as many proposed explanations for this as there are depressed people. Could it be that marketing of antidepressant meds leads to more diagnosis? Is some aspect of modern life to blame?
A recent study suggests that a contributing factor, and maybe even the cause, of this rise in depression is exposure to light at night. When we watch TV, work on our laptops or stay up late doing chores in a light-filled room we may be interfering with our body's biochemical processes in a way that results in depression.
The researchers exposed female hamsters to dim light during eight hours out of every 24 (and regular light the other 16) for four weeks and found that the hamsters began to exhibit depression symptoms. What, you may well ask, is a depressive hamster behavior? They lost their appetite for sugar, and when they were placed in water they didn't try to swim to safety as vigorously as they should have. The exposure to light and night also caused physiological changes in the hamsters' brains that are associated with depression.
I will definitely try to keep it in mind the next time I'm working on my computer as the clock strikes ten or eleven (read, almost every night) and haul my butt off to bed in a pitch black room.
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