A 44-year-old man reports 1 week of increased activity assoc…

A 44-year-old man reports 1 week of increased activity associated with an elevated mood, a decreased need for sleep, and inflated self-esteem. Although the man does not object to his current state (“I’m getting a lot of work done!”), he is concerned because he recalls a similar episode 10 years ago during which he began to make imprudent business decisions. A physical examination and lab oratory work are unrevealing for any medical cause of his symptoms. He had taken fluoxetine for a depressive episode but self-discontinued it 3 months ago because he felt that his mood was stable. Which diagnosis best fits this clinical picture? 

A relatively recent discovery has been that new neurons can…

A relatively recent discovery has been that new neurons can be generated in certain brain regions (particularly the dentate gyrus of the hippocampus) in adult animals, including humans.  This is is contrast to the previous belief that no neurons were produced after birth in most species.