Vanda's Sleep Disorder Drug Tasimelteon Shows Promise

[bananas]

8. Also astronauts, jet lag, and sundowners.

The implications for astronauts and jet laggers should be obvious.
The implications for the rest of is much more subtle.
My mother had this, it was like a switch being flipped at sundown:

http://en.wikipedia.org/wiki/Sundowning

Sundowning is a psychological phenomenon associated with increased confusion and restlessness in patients with some form of dementia. Most commonly associated with Alzheimer's disease, but also found in those with mixed dementia, the term "sundowning" was coined due to the timing of the patient's confusion. For patients with sundowning syndrome, a multitude of behavioral problems begin to occur in the evening or while the sun is setting.[1][2] [3] Sundowning seems to occur more frequently during the middle stages of Alzheimer's disease and mixed dementia. Patients are generally able to understand that this behavioral pattern is abnormal. Sundowning seems to subside with the progression of a patient's dementia.[1][2] Research shows that 20–45% of Alzheimer's patients will experience some sort of sundowning confusion.[1]

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