Sometimes, the tail can wag the dog of diagnosis. An illness may be revealed over time when, for example, a patient responds to a treatment. Response to a mood stabilizer like lithium or valproate acid supports the diagnosis of bipolar disorder. Improved symptoms due to antidepressants might support a diagnosis of a psychiatric disorder, but it may not help distinguish a depressive illness from an anxiety disorder since antidepressants help both conditions. The logic of the diagnostic process is deductive. Deductive reasoning is the method of Sir Conan Doyle's Sherlock Holmes (and his heirs from Lt. Columbo to Dr. House) -- a valuable and timeless means to untangle the mysteries of many a science.
There are times, though infrequent, when special brain scans (Magnetic Resonance Imaging or MRI) are needed, and times when psychological tests can be helpful. Neuroimaging, or radiological tests of the brain or spinal nervous system, can assist in diagnosis when used to examine for a physical illness that could explain a person's disorder. Depending on the study, a brain scan can look at anatomy or at the functioning of the brain. Brain scans are commonly used to detect tumors, blood vessel or bleeding abnormalities, skull fractures, or loss of brain tissue (as seen in Alzheimer's disease and the more recent promise to detect it early).
But, these scans are not employed for initial psychiatric diagnosis. Instead, scans are used to determine the absence of a neurological lesion, rather than pointing out the presence of a behavioral condition. MRI's cannot diagnose schizophrenia or bipolar disorder, but they can identify a tumor or a stroke that may have similar psychiatric manifestations. While we are seeing truly fascinating results from neuroimaging -- from unraveling complicated brain depression networks to staging dementia -- it has yet to serve as an anchor for psychiatric diagnosis.
Psychological testing has come a long way from the days of Rorschach's inkblots. Intelligence and other tests of cognitive functioning, administered by an expert psychologist, can help to identify problems with mental attention, focus, and decision-making. There are tests that can help in the workplace, the best known being the Myers-Briggs, which profiles how people think and feel -- and can be useful in understanding (and getting along with) our co-workers. There are tests that can track the progression of dementia. The mother who asked about psychological testing was wondering if personality and projective (looking into the workings of the mind) testing could make a difference in diagnosis. Not today, we say.
For over a decade, scientists have been detailing the human genome and trying to target treatments based on individual genes that might predict response (or lack of it) to specific treatments. Patients, families, and practitioners have remained hopeful that genetic evaluations will influence clinical decisions. Dr. Harold Varmus, former head of the National Institutes of Health, said -- and we paraphrase -- the human genome is good for science but not for medicine. You or your family member may want to participate in rigorous and safe psychiatric genetic research, but don't waste your time, money and precious hope on a gene that someone says will change the course of treatment or recovery. Not yet. And while you consider imaging to rule out other physical disorders, these scans are, alas, not yet able to establish a psychiatric diagnosis. Soon, we hope.
Mental disorders are rapidly becoming the leading causes of disability worldwide.
They also contribute substantially to the burden of the chronic physical illnesses (like heart disease, asthma, diabetes, cancer, and stroke) that now dominate global public health. We need better psychiatric diagnostics (and treatments). Neuroscience research continues to reveal more about the brain and is the path for the discoveries we so deeply need.
But until scientific inquiry yields results that can be used in everyday clinical practice, too many people remain ill, impaired, and at risk of taking their lives. For now, when an illness eludes our ability to explain its cause(s) or persists in you or your loved one, you will want to be prudent - and not a desperate shopper. You can and should seek further consultation and more careful evaluation. But be wary of diagnostic tests (and treatments) that are not yet ready for prime time.
Instead, learn about your condition. With your doctor, and other caregivers, relentlessly monitor response to treatment and insist on proven diagnostic inquiries and treatments that are comprehensive and continuous in their delivery. When improvement is not happening, ask why -- and insist on an answer. Seek out caregivers who are firmly rooted in the conviction that you can get better and live a life like everyone else. Don't settle for less. There is so much that can be done to help people with mental illnesses, even if the tests are not yet here to tell us why the treatments work.