12/09/2011 08:45 am ET Updated Jan 04, 2012

DSM Diagnosis: How Do You Know If You Have Mental Illness? (VIDEO)

Hey everybody. Cara Santa Maria here. How many times have you said to yourself, "I'm so depressed today." Or "I'm totally OCD about my closet. It weirds me out when anything's out of place."

Does this mean you have a mental illness? How is mental illness diagnosed? And is the line between healthy and mentally ill fuzzy or absolute?

Well, abnormal psychology is a science. And most scientists and medical professionals agree that abnormal behavior is indicative of underlying mental illness.

Which brings us back to my original question... what is a mental illness? How do you know if your mood or thought processes are normal or abnormal? And how do you know whether or not you would benefit from treatment?

Let's say your mood or your thoughts are starting to interfere with your life. You may decide to see a mental health professional. When you sit down in the psychologist or psychiatrist's office, they'll ask you some questions and may have you take a few tests before they decide whether your symptoms warrant a clinical diagnosis. Next, your doctor will generally turn to the "psychiatrist's bible," also known as the Diagnostic and Statistical Manual of Mental Disorders, or the DSM.

If you're diagnosed using the DSM, you'll be assessed across five axes. The first axis includes any and all clinical disorders, such as eating disorders, schizophrenia and other psychotic disorders, mood disorders like depression and mania, and many many more. On the second axis, your doctor will decide whether or not a you have a personality disorder (like histrionic, antisocial, or borderline) and whether or not mental retardation is present. Axis three is for reporting current medical conditions that may be relevant to the treatment of a mental disorder.

For example, if you have cancer, it could be contributing to your major depressive symptoms. In axis IV, your doctor will make note of the factors that may make your recovery more difficult: if you can't get to the clinic, don't have many close friends or relatives, or recently lost your job or home. Lastly, axis V is a place where your psychologist or psychiatrist makes judgments about your overall mental health. It's called the Global Assessment of Functioning scale and it can be rated anywhere from 1-100. 1-10 says that you're danger of severely hurting yourself or others OR that you're unable to maintain minimal hygiene OR that you are hellbent on committing suicide. Ratings between 91 and 100 indicate that you have superior functioning on a wide range of activities; basically, you're completely asymptomatic. But let's be real; extremely high and extremely low scores on the GAF scale are pretty rare.

When it comes to mental health research, diagnostics, and treatment, knowledge is power. Know yourself and know your doctors. If you've been diagnosed with a mental illness, read about it, and find out what you can do to manage it. We'll be engaging in a month-long conversation about the science of mental health, touching on topics like depression and anxiety, schizophrenia and bipolar disorder, and autism and ADHD. We'll be looking at current trends in mental health illness research as well as investigating and questioning current diagnostic and treatment models. I hope you'll join the conversation. Hit me up on Twitter, Facebook, or leave your questions and comments right here on my blog. Come nerdy to me!

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