The origins of depression have long been studied and pondered by researchers and psychologists. In Massachusetts, scientists at MIT recently postulated that pessimism, for example, is influenced by stimulation of a brain region known as the caudate nucleus.
Among the biological, psychological, and social explanations put forth by various scientists throughout decades, one theory persistently seems to be brought up the most and that is the chemical imbalance theory.
There is something liberating about linking mental conditions exclusively to biological malfunctions. Broken things can easily be fixed when the cause is just a misadjustment. For a disorder as prevalent as depression, however, this oversimplification may overshadow the numerous convoluted factors underpinning the problem.
For sure, everything psychological is biological. Depression is not just a bad mood that you can shake off; something in the brain has to be functioning incorrectly and chemicals are involved to a certain degree, but the question is the causation. The question is that whether the brain’s altered state is the effect or the cause, and in either case, what the exact contributing factors are as they remain unclear to this very day.
If chemical imbalance was the sole cause, then antidepressants would be the sole solution effective for everybody which we know it’s not the case. But to elaborate any further, we first need to discuss the chemical imbalance theory and its origins.
Neurotransmitters and Elevated Mood
Commonly referred to as chemical messengers, neurotransmitters are substances that the nervous system uses to send messages between the nerve cells or from nerve cells to muscle cells and gland cells. Neurotransmitters are used by the brain to help regulate a myriad of essential functions in the body such as breathing and digestion. There are over 500 identified neurotransmitters in the human nervous system some of which regulate our mood and affect how we experience pleasure, pain, and anxiety. Dopamine plays a role in how feel pleasure, GABA influences how experience anxiety, fear, and stress, noradrenaline affects alertness and arousal, and serotonin is a mood stabilizer that affects our feelings of well-being and happiness.
The chemical imbalance theory is predicated on an assumption that since higher levels of serotonin in the brain can lead to an elevated mood state, therefore, lower levels of serotonin in the brain are the cause of depression in the patients which can be readjusted and corrected by drugs.
The problem with this theory is that it ignores all the intricacies and nuances of the complex processes in the brain that are still poorly understood. Instead, it tries to fix an apparently broken part, without fully comprehending how the bigger and more complicated overall system works. Emotional states are the result of a variety of different elements including automatic behaviors, social relationships, environmental cues, cognitive interpretations, and physiological responses. A chronic mood disorder cannot be reduced to a mere chemical imbalance, isolated from all the other factors that may have created the imbalance in the first place.
On the other hand, there are no credible scientific studies that show that chemical imbalances in the brain cause any psychological condition. An analysis of 522 trials involving 21 antidepressant drugs with 116,477 patients showed that the efficacy of the drugs was barely better than placebo.
Moreover, there is no method for measuring neurotransmitters like serotonin in the brain. This means that when prescribing SSRI antidepressants, we don’t factually know that the patient suffering from depression has low serotonin levels in their brain. This does not mean that antidepressants never work. They do seem to work but for a small minority of severely depressed patients whose number by no means match the 16% of American adults who have taken these drugs.
The Better Alternative
A long-standing alternative to the chemical imbalance theory is the bio-psycho-social model where psychiatric experts look at a combination of biological, psychological, and social factors for causes of a mental illness. As an alternative, this model does not deny the possible biological roots of depression. Rather, it considers biological factors as one of the main components of the overall state of mental health. Physical health, genetics, social influences, culture, belief systems, and socioeconomic status all fall under the domain of causes for depression.
It’s by carefully examining these three aspects of a patient’s life that mental health professionals can truly gain perspective as to what have factors have contributed to the development of the illness.
For example, the biological alteration in the patient’s brain may have been caused by substance or alcohol abuse which in turn, may have been facilitated by the patient’s genetic predisposition to addiction whose self-perpetuating cycle can be broken by drug and alcohol treatment.
The bio-psycho-social model enables us to see the causes, not as isolated instances, but as a string of interrelated factors that is unique to each suffering individual. There is more to treating psychiatric disorders than suppressing symptoms. Delving into the roots of these disorders and bringing them to the surface is the only way to get permanent and life-changing results.