Mental Disorders Vs Diseases

Is there such a thing as a mental disorder that is not akin to a biological disease? Biological psychiatry says absolutely not. For them, all mental disorders are biological disorders involving some form of breakdown in brain circuitry. The power of this view was on stark display over the past week. As has been much discussed, a week ago the director of the NIMH, Thomas Insel, sharply criticized the DSM system and stated that the NIMH will instead be organizing its research around a new nosology that attempts to link several different domains. Will this new nosology finally attempt to separate those psychological problems that are reducible to biological dysfunction from those that are not, as I have argued previously? No.

A central, guiding assumption of the new NIMH system is that: “Mental disorders are biological disorders involving brain circuits that implicate specific domains of cognition, emotion, or behavior.”

This is an even greater commitment to biological dysfunction than the DSM makes! Why is this foundational assumption made? There are two basic reasons. The first reason is that because everything that is psychological (or mental) is also biological, it follows that mental disorders must also be biological disorders. More on this assumption below.

The second reason is political and institutional. The DSM—and to a large extent the NIMH—is owned and controlled by psychiatry, and psychiatry is a branch of medicine. Thus there is a core identity issue here. If psychiatry is a true medical discipline, then it must treat real diseases like the rest of medicine. It can’t just be about generic “problems in living,” even if very severe. Thus, the above assumption about biological dysfunction is central to their professional identity.

Now, back to the first assumption. As a psychologist who believes our discipline ought to be committed to a naturalistic worldview, I agree that all psychological/mental phenomena involve biological phenomena. There is no psychology without biology. But that does not mean the mental is the same as the biological. Nor does it mean that you can reduce the mental to the biological. And, ultimately, it means you CAN have psychological disorder without biological/brain malfunction.

First, though, let’s start with a clear case that affirms neuropsychiatry. My grandfather began forgetting things when he was in his 80s and by the time he passed, he could not remember what had just happened to him. Diagnosed with Alzheimer’s, it is easy for us to imagine that it was the tangles and plaques in his temporal and parietal lobe, along with other neurological breakdowns, that manifested in his loss of memory function. Even though the primary symptoms of were psychological/mental behavioral, he obviously suffered from a mental disease. The point here is that if the brain breaks down in its basic functioning, then there will be psychological dysfunctions that follow. So, there certainly can be mental disorders that are akin to (and essentially reducible to) brain diseases.

But that this is true does not mean the reverse is always true. When I was in high school, I found myself having strong feelings of attraction toward a friend’s girlfriend. They broke-up and then a few months later we started dating. I felt great. Then she dumped me and started dating a small, “punk rocker” who was a year younger than me. I couldn’t believe it. Not only was my heart broken, but my pride was also deeply injured. She knew me well. She liked me, but for some reason not in “that way.” And it wasn’t the first episode of this flavor for me. After it happened, I suffered with a somewhat negative mood for several months. Not a depression, more of an adjustment disorder with depressed mood.

Now, I don’t doubt that if we had a brain scanner on me, we would see that during this period, my brain changed. My right side, with its stronger role in negative affect, would probably have been more active. Perhaps my amygdala would have also been a bit more reactive to threat. Perhaps my frontal lobe would have been a bit shut down and that would have corresponded to my difficulty focusing on my studies.

But was I suffering from a brain malfunction? No. Of course not! My brain was functioning exactly how it should. But I was definitely having a “problem in living” that edged up against clinical significance. Thankfully, I had a good relationship with my brothers, friends, and parents, and a few months later I met a young woman who would become my wife. So the resources turned around, and the story ends happily. But what if those things had not there? Then I might have suffered more, had more negative affect, had more trouble for longer periods in school, had difficulty thriving in any endeavor, and felt worse and worse. Then it would clearly amount to “clinically significant” levels of distress and dysfunction. But there still would not necessarily be ANY brain dysfunction. There is no reason that clinically significant levels of distress and dysfunction at the level of psychology would correspond, one to one, with brain malfunction!

Here is the bottom line. The brain and nervous systems have been designed by evolution to be designed by experience and learning. This means there is no prototype for how brains function that map directly on to psychological level processes, like an American high schooler being rejected in love and feeling down about that. The fact that the nervous system was designed to be designed by learning means there are many different potential pathways of development. Some of these will involve suffering and maladaptive patterns that do require mental health assistance but are NOT in any way shape or form reducible to brain malfunction. Unfortunately, psychiatry, with its identity as a medical profession, can’t accept this basic truth, and that is one of the main reasons why it is currently in crisis. Either that or it is because the brains of psychiatrists are malfunctioning.