THURSDAY, Jan. 2 (HealthScoutNews) -- Cocaine users seek pleasure, but the more they indulge in the drug, the less likely they are to feel the pleasure they're seeking. That's the finding of a new study that shows cocaine damages brain cells that trigger the feelings of pleasure. The drug also exerts its most serious effects on those who are clinically depressed, the researchers found. This is the first time research shows what happens "in those humans with the most clinically significant cocaine dependency problems," says Dr. Karley Little, chief of the Veterans Affairs Healthcare System in Ann Arbor, Mich., and...