“It’s a chemical imbalance.”
You may have heard or said those words before in reference to mental illness. I have done both myself a number of times in my practice as a primary care doctor. One good example of opening the conversation about them can be found here from Ed Stetzer; one of Stetzer’s explicit goals is to decrease shame and stigma against mental illness by locating the pathology of mental illness in neurobiology and then asserting the need for medication to rectify the dysfunctional biology. As Christians across the world grapple with the modern understanding of mental illness, it is helpful to not only understand what these imbalances are and how medication might address them, but also to challenge a point of view that reduces mental illness to a mere malfunction of biology.
The impetus behind the use of the words "chemical imbalance" is good. After all, confining mental illness solely to the untouchable realm of feelings and thoughts is not only ignorant of biology, but also of orthodox anthropology. Furthermore, such a harsh dichotomy happens to be extraordinarily ineffective in the lives of most sufferers of mental illness. You may or may not have heard of an excellent book that sought to make clear the theological importance of our physical bodies; affirming that deficiencies or excesses of certain chemicals in our brains play a role in mental illness is an important step in the process of rightly treating our bodies as part of the created order. In turn, the judicious use of other chemicals to rein in the torment and harm caused by mental illness is as much a part of using our God-given power to exercise dominion over the earth as is carefully using pesticides on our crops so that more people can eat.
However, saying "you've got a chemical imbalance" does not go far enough and, paradoxically, can often take us too far in the wrong direction.
Assigning mental illness solely to such imbalances is inadequate firstly because it underappreciates the complexity of neurobiology. For example, we know very well that people with depression have lower serotonin levels (most potently demonstrated in studying the brains of those who have committed suicide.) Selective serotonin reuptake inhibitors (SSRIs) such as Prozac or Zoloft raise serotonin levels in the brain. However, while many of the measurable effects of SSRIs on neurons can be seen within hours of first taking the drug, the effects of these medications are rarely appreciated until at least 4 to 6 weeks, making it far from clear that raising one's low serotonin levels is their sole useful effect. Furthermore, the fact that any of these medicines has roughly a 30-40% chance of working in isolation on the first try is evidence that any "imbalances" we discuss are less like our car's windshield wiper fluid and more like our food's soil. When dealing with even more complex illnesses like bipolar disorder (which responds to a wide range of medications that are also effective for epilepsy) or schizophrenia (which involves a greater variety of neurochemical pathways), it is clear that the language of "chemical imbalance" is simply a starting point.
Secondly, while it is obvious that there are many aspects of brain biochemistry that we cannot consciously control, there are many others that we can. The choices we make shape our physical bodies-- including our brain structure and genes. This is most apparent in the cycle of addiction, wherein an addict's brain is often demonstrably altered to have a minimal response to normal pleasurable stimuli and to require greater and greater doses of the drug of choice to not feel agonizing withdrawal. However, as we learn more about the bodies that God has given us, we see that chronic stress and traumatic events (often caused by the sin of others) can shape the brains of children with immature decision-making ability in ways that last for a lifetime. Thus, there is a reciprocal relationship between our environment, our bodies, and our feelings. Both our moods and our decision-making abilities are shaped by constant internal decisions and external stimuli.
The most potent example of this principle is the case of a sexually abused child who overeats not only to soothe the excess quantities of stress hormones that may or may not be predisposing them to depression later in life, but also to appear less attractive to their abuser. Even without immediately jumping to the conclusion insisting that the government must do something (as part 3 of the article linked above does), it is clear that we must jettison any simplistic understanding of the complex interaction between brain and body as a matter of individuals choosing to either sinfully wallow in mental illness or righteously embrace freedom in Christ. Similarly, we must also not succumb to a materialistic view that defines people stuck in mental illness solely as victims of circumstance.
We go too far in the wrong direction in this manner when our appreciation for the power of pharmacology to help guide our brain chemistry into a more ordered pattern becomes a helpless veneration of medicine. I have seen this, too, in my practice-- patients who have been trained to believe that their own efforts to calm their nerves or pay attention are useless when compared to the power of Xanax or Adderall. The danger of these medications is that they are powerful enough to abrogate our efforts; as prescriptions for these (and similar) medications continue to dominate the market in a way that disquiets many clinicians, a sense of restraint and discipline is necessary for all parties involved.
Health is a discipline. The bodies that God has given us require care and attention to maintain in a way that fits the pattern he established for our being; while our appetites can sometimes be helpful guides to our needs, they are often magnified or minimized by sin in such a way to lead us astray. Whether we are choosing certain foods, actively exercising, or avoiding other substances, our health requires active management and control.
These individual choices are also clearly shaped by our environment, from the simple unavailability of fresh vegetables in certain neighborhoods to the more complex changes caused by chronic stress described above. Disciplines, while individually practiced, are shaped by the communities that we live in and the values we collectively affirm. Wendell Berry points out that "autonomy" is a false cure for our modern ills, saying, "Healing is impossible in loneliness; it is the opposite of loneliness." When we do not pay heed to the disciplines-- either individual or environmental-- that shape our health, the breakdown of our bodies is attended by the breakdown of our minds and spirits.
In regards to mental health, it is often said that "food is the most overused antidepressant and exercise is the most underused antianxiety medication." A variety of well-designed studies have borne out the efficacy of behavioral interventions for a variety of mental illnesses, demonstrating that our power over mental illness is not limited to pharmacology. That said, anyone who has ever seen a loved one struggle to take medication for mental illness can see that even the act of using pharmacology's power (and bearing its side effects) is itself a discipline. Even more telling are the studies that show that some of the sickest people who burden emergency rooms with repeated visits see great improvements in their physical and mental health when they are brought into closer personal contact with caring people and housed.
Talk of health as a discipline or health choices as being shaped by culture brings to mind the issue of personal responsibility, which is a useful rallying cry for helping oneself feel less perturbed about the suffering of others, but by definition cannot be embraced as a corporate policy. Personal responsibility is clearly a component of discipline, but it is not the only one. For those who are struggling with mental illness, it is imperative they are approached first as persons with dignity whose ability to make rational decisions and take responsibility has been impaired-- whether by themselves, by another, or by the happenstance of neurobiolog. Once this relationship of trust and respect is established, we can walk with them through both the personal and professional interventions necessary to learn or rediscover the skills that attend to personal responsibility.
Similarly, shame can be useful; the things that people with mental illness say and do when swayed by the winds of their depression or mania are often a powerful motivator to change their behavior when they feel ashamed of them. While we want to rightly eradicate the effects of shame that keep people from seeking help and being honest, it is possible to strain out a gnat and swallow a camel if we take the language of "chemical imbalances" too far and put personal responsibility out of reach for those who suffer from mental illness.
In the end, both the people who wish to eradicate shame from mental illness and those who wish to use it as a hammer for every health-related nail they see will find themselves in conflict with a holistic worldview that embraces the continuity between physical existence, knowledge, indiscernably complex emotions, and meaningful spirituality. The bodies that God created us with are prone to the corruption of sin in ways that science can both illuminate, abet, or help to heal-- but only if we can appreciate the full complement of healing means that He has given us.