March 29th, 2011
06:51 PM ET
Every weekday, a CNNHealth expert doctor answers a viewer question. On Tuesdays, it's Dr. Charles Raison, an associate professor of psychiatry and behavioral sciences at Emory University, and an expert in the mind-body connection for health.
Asked by RN, Central Washington
I am having significant memory problems that my M.D. thinks are due to depression, but I wonder if such severe problems can be accounted for by depression. I have had dysthymia my whole life. I admit I have a lot of stress in my life and may even be more depressed than I have been in the past, but I have never had these problems before. Here are some examples of things I forget on a daily basis (multiple times a day, actually) : not knowing why I'm in the car driving, not able to remember longtime friends' names, my dog's name, can't remember the names of common objects, putting keys, laundry, etc. in the refrigerator. This is affecting my professional and personal life. Could this really be just depression?
I wish I knew how old you are, because this is by far the most important factor in determining how likely it is that depression is causing your cognitive symptoms, as opposed to some other process like dementia. Assuming you are not abusing drugs or alcohol and have not developed some very, very rare disorder, there aren't many likely causes for your symptoms.
If you are under the age of 60, your M.D. is likely correct. If you are over the age of 60 (and there is nothing magic about this exact age), the risk for dementia, which could also be causing your problems, increases dramatically. By the way, this pattern holds for all mental complaints. If a person begins having hallucinations at age 20 it is almost always a psychiatric problem. If a person has hallucinations for the first time at 80 it is almost always medical or neurological problem.
Whatever your age, if it were me I would get neuropsychological testing. This testing is an involved and expensive process not covered by all insurance policies, but it is pretty good at identifying a dementing from a depressive process. Again, the older you are the more such testing is likely to be revealing and therefore important to do. Also, if you are older, neuroimaging can sometimes be useful in identifying obvious physical causes for these symptoms, such as small strokes in the brain.
Let me assure you that major depression can most definitely be associated with severe problems with memory, paying attention and other cognitive abilities. In fact, in older people, these deficits can be so severe that they can actually pose a diagnostic challenge in terms of differentiating them from dementia. Certainly of the symptoms you list, only putting the laundry in the refrigerator would be a little unusual for major depression.
If your symptoms are being caused by depression, you should know that the presence of these symptoms in the disorder is no accident. Probably the most replicated neurological finding in depression is that a part of the brain called the hippocampus shrinks. This area is crucial for all the memory abilities you describe. Although some data suggest that the hippocampus can recover with treatment, clinical experience suggests that cognitive complaints can persist and resolve only slowly.
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