[pddpro]

Anecdote but I always noticed change in sleep patterns after starting antidepressants. Actually, terminal insomnia (you wake up and then are unable to fall asleep) are characteristic of chronic depression. Add to this that SSRI causes increase in sleep hours (maybe even quality?) and then you have a theory about how it might just have been due to lack of sleep after all?

[cpncrunch]

Given the placebo effect is 75% of the effect of antidepressants, and placebos have a large effect on sleep, I would say that the placebo effect is the first thing that should be considered.