More than 19 million Americans suffer from depression, but fewer than half seek treatment. As WNPR's Jeff Cohen reports, Thursdsay/last week was National Depression Screening Day -- a push to get more people to the doctor's office. David Wheeler is a clinical psychologist at Natchaug Hospital in Mansfield. And he says there's one important thing to keep in mind when it comes to mental health -- all abnormal behavior is an exaggeration of otherwise normal behavior. "Everybody has down days, everybody gets anxious about some things, everybody obsesses from time to time, everybody has strange thoughts, everybody hallucinates at times. These are normal." But imagine that anxiety you feel when you're about to take a test or close on a house or apply for a job -- and then imagine it sticking with you all of the time. For weeks. Wheeler: When it gets to that point and it starts to interfere with your life, you're not enjoying yourself as much, things aren't going very well, now you're starting to have a problem and now's the time to do something about it." Cohen: So it's not the behavior itself alone, it's the frequency with which you.... Wheeler: Frequency, intensity, and duration. So the point of the recent National Depression Screening Day was to raise awareness about the importance of screening so people recognize the signs of a mental health issue and see a doctor if necessary. Wheeler: Unfortunately, what most people do is they wait 10 to 15 to 20 years to do something about it. Cohen: And what's the result of that? Wheeler: Well, it's become a well-entrenched habit and at that point in time it's a lot harder to change. You can take an online screening at www.helpyourselfhelpothers.org. For WNPR, I'm Jeff Cohen.