I've been puzzling over an old question. What is mental? What is physical? The most recent DSM (Diagnostic Statistical Manual for Mental Disorders IV) describes the separation of mental and physical as "a reductionistic anachronism of mind/body dualism." That dualism—we are made of two things: spirit and matter—is very old, but it is a philosophical conundrum of the most befuddling kind, and the authors of the DSM want to make it clear that they haven't fallen into that trap. They do not define the two, however. They are hedging their bets by saying that psyche and soma can't really be separated. Every mental state is also physical. My question is why do we have "mental disorders" at all, if the current wisdom is that they are really physical? Schizophrenia, bipolar disorder, OCD, depression, and other "mental" afflictions are now often referred to as "organic brain diseases." The popular press is especially fond of this terminology. What has happened?
For years, psychiatry distinguished between an organic illness and a functional one. If a psychotic patient was found to have a brain tumor—a cause that could be seen and identified—he would have an organic problem, but if there were no sign of a cause for his symptoms, he would be labeled functional. The DSM IV threw out these categories. The pressing reason for the change came from research that confirmed brain abnormalities in people suffering from a functional illness. Enlarged brain ventricles and reduced gray matter are characteristic of schizophrenia, for example, but no one knows what causes these organic differences. Schizophrenia remains a medical mystery, but twin studies suggest that both genetics and environment play a role.
I have discovered that many people use the term organic brain disease as if it explains everything when, in fact, it explains very little. All human states are organic brain states—happiness, sadness, fear, lust, dreaming, doing math problems and writing novels, and our brains are not static. Neural networks develop, are "wired," over time in relation to our experiences. Environment can affect genetic expression. What scientists call "cognitive factors," in other words, thoughts, also influence physiology. Think of the well-known placebo effect. Believing that the pill works appears to release endogenous opioids in our brains that make us feel better. But as the neuroscientist Joseph Le Doux writes in his book The Synaptic Self, "The Problem is that it is not clear how the changes at the neural level relate to those at the psychological level." When we look inside someone's skull, we do not see thoughts or dreams or delusions or words, we see two hemispheres, white and gray matter—we see an organ. So scientists speak metaphorically of levels, as if one were on top of the other—the physical level of neurons and synapses and neurochemicals and hormones—and the psychological level—what we experience internally as our own minds with our memories and feelings. They use terms such as neural substrates, neural correlates, and neural representations. Le Doux has studied the neural correlates of fear. A puzzling gap, however, remains between the two "levels."
Language is important because it shapes our understanding. We live in a culture that is much happier talking about organic brain disease than about psychic illness because the former suggests that something that is physically wrong in a brain is wholly unrelated to that person's upbringing or experiences in the world, but that is not necessarily true. Scientists are beginning to understand how early parental care in relation to genetic factors influence how our brain functions and how we develop. The brain is an immensely complex organ and many mysteries remain. Exactly how brain and mind or soma and psyche are related is one of them.