Psychiatric Diagnoses: Behavior Problem or Brain Disease?
How to tell a legitimate brain disease from a behavioral syndrome.
Posted May 13, 2019
When the first edition of the Diagnostic and Statistical Manual of Mental Disorders or DSM (the manual of psychiatric diagnoses published by the American Psychiatric Association) came out in 1952, it listed about 100 different psychiatric diagnoses. By the time the fifth edition was published in 2013, it listed over 550 separate ones! One has to wonder if early psychiatrists were just missing a bunch of them, or if normal but repetitive everyday problems in living due to trauma, stress, and interpersonal dysfunction have been turned into diseases. I vote for the latter.
The DSM writers consciously chose to avoid answering this question by merely describing clusters of symptoms and leaving the question of the actual causation of these clusters for future generations. Etiology, schmediology!
The question as to whether given diagnoses in the book are actual brain diseases or just psychological or behavioral problems experienced by normal brains is complex—because the phenomena under discussion are unbelievably complex. While our understanding of the brain is increasing by leaps and bounds, it is still very rudimentary. That is because the brain is literally the most complicated and complex object in the entire known universe, with about a trillion constantly changing connections between nerve cells. Remember when computers would go crazy and produce the infamous “blue screen” when two programs would conflict, and you would have to restart? Imagine what might happen if the computer were not hard-wired!
Then there is the fact that there are literally thousands of environmental variables operating, each on their own schedule and in various combinations and varying levels of severity over time, that affect the structure and functioning of the normal brain. On top of that, chaos theory predicts that because of this, small changes in initial conditions can lead to huge differences later on. This means that no scientific study can really control for all the relevant environmental risk factors. Add free will into the mix, assuming it exists, and fahgettabout it!
It should be said that a lot of people, including many in the various mental health professions, seem to be prone to highly simplistic “either-or” thinking. If even one of the 550 DSM diagnoses is a brain disease, then they all must be. Or if one is a behavioral or psychological disorder, then they all must be. That is just stupid. But throughout the history of psychology and psychiatry, the field has often lurched back and forth between brainlessness and mindlessness (as described in Chapter One of my book on dysfunctional families and mental disorders), incorporating what turned out to be ridiculous or misguided theories.
Autism is caused by refrigerator mothers. Schizophrenia is just a different way of experiencing the world or due to being placed in a double bind by your family. Sexual promiscuity is a genetically determined trait, and certain races are genetically inferior to others. Acting out by children is caused by underlying bipolar disorder. Obsessive-compulsive disorder is caused by harsh toilet training. A central part of women’s psychology is penis envy.
The list of nonsensical and grossly mistaken theories like these is nearly endless. I’m surprised that no one ever theorized that the memory deficits in Alzheimer’s disease are really a manifestation of the defense mechanism of repression.
But even without such simplistic thinking, designing a study to make a determination about which diagnoses are truly diseases, and which are primarily behavior problems caused by problematic learning and stress, is no simple task. You cannot, for example, just do an fMRI brain scan, as I described in an earlier post, because that test alone does not distinguish an abnormality from a normal conditioned response to a particular social environment.
And even if something is a brain disease, family stress and dysfunction can make it worse—just as also happens with many physical diseases. Then there’s this: Having a parent who gets manic and runs naked through the streets creates huge environmental stresses for a child who observes it. Such children are at risk both genetically and environmentally.
Not only that, but you get into a chicken and egg situation: does having a controlling family create anorexia nervosa, or is having a child who is starving herself to death lead parents to become overly controlling? A child who is more temperamental is often somewhat more difficult to raise than one who is not, leading some parents to engage in problematic parenting practices with one of their children but not others.
But wait, there’s more! The whole question of “what causes” a disorder is further complicated by the fact that with the vast majority of psychiatric diagnoses, there are no necessary or sufficient causes of any sort—only risk factors that increase the odds someone will develop a disorder by a very small amount and mitigating factors that decrease those odds.
So how do we go about making an educated guess as to whether a disorder is a disease or merely dysfunction? What standards do I personally use in forming my opinions about various disorders?
To me, by far the most important metric is whether or not the symptoms of the disorder only appear under certain social conditions and disappear when the social conditions change. Real brain diseases, like schizophrenia, don't do that; they are present almost all the time. You see victims “responding to internal stimuli” whether you are talking to them one-on-one or observing out of the corner of your eye on a ward in a state hospital when they don’t realize they are being observed by staff. They show them no matter who is talking to them, or even if they are put alone in a room in a psychiatric ER with a hidden video camera keeping a watchful eye on them.
Someone with, say, a melancholic depression reacts at a snail’s pace compared to the way they usually react (psychomotor retardation) every waking moment, no matter where they are or who they are with, and stay in that state all day every day, sometimes for weeks at a stretch. Luckily, when I trained, we could keep patients in the hospital that long so we could see this; today’s trainees do not get to do that any more, and so are more easily fooled.
On the other hand, borderline personality disorder symptoms are not like that at all. I would see patients with the disorder acting out with staff in a psychiatric hospital, but behaving completely appropriately with the other patients when they didn’t know I was observing them. In fact, they are famous for acting one way in the presence of certain staff members and exactly the opposite when in the presence of others, leading the two groups to fight with each other (the infamous staff split)!
I’ve seen people I know have the disorder out and about at music festivals and theaters acting as normally and appropriately as anyone else. In therapy, certain emotional reactions and provocative behavior would come out of them if the therapist did one thing, but would disappear quickly if the therapist changed to doing something else.
In looking at neuroscience evidence, one additional metric I use to distinguish disease from mere dysfunction is the sheer number of different types of brain differences and other neurological findings. As I said, a single fMRI finding alone tells you nothing. But a whole bunch of different fMRI differences, with some of them completely unrelated to the symptoms of the disorder, suggests a brain disease.
For example, people with schizophrenia tend to have a lot of differences in their brains from those who do not, many of which have nothing to do with delusions or hallucinations. One cannot be certain, of course, but I would be hard-pressed to explain many of these neurological findings in terms of conditioned responses to particular social environmental stimuli.