Reducing the Brain, Ignoring the Soul
Grace E. Jackson, MD
December 5, 2002
The TV commercial shows a bouncing ball, frowning before the onset of therapy with the appropriate pill. The announcer reminds viewers that they may be suffering from a chemical imbalance, for which medical help is readily available. They should ask their doctors if they have symptoms of clinical depression for which the specific remedy should be swallowed. The ad closes with a picture of the animated ball (post-medication), smiling broadly before skipping out of view.
A psychiatry residency program drills its junior clinicians in the art of medical clearance. Before any patient may be admitted to the inpatient psychiatry ward, the admitting resident must demonstrate that symptoms are not the result of an undiagnosed or unstable "medical" condition. To this end, vital signs are taken; EKGs and x-rays are performed; and a variety of blood and urine tests are obtained. Only if, and when, a patient's neurobehavioral symptoms are determined to be non-organic in origin (or if organically caused, then the product of a stable underlying condition) is the patient deemed appropriate for treatment on the psychiatric ward of the hospital.
"Non-organic in origin." "Medically cleared." Then the same psychiatrist determines that the patient must be treated for a medical condition, with pharmaceutical agents. The doctrine of biological psychiatry commands its adherents to medicate people for speculative or presumptive chemical disorders, despite the lack of evidence that such a disturbance ever exists.
There are at least five problems with the chemical imbalance model of mental disease:
1) the model ignores the reality that there has never been a consistently reproducible biological marker, to substantiate the levels of normal or abnormal neurotransmitters in the human nervous system
2) the model fails to respect the enormous complexity of neurotransmission in the human brain:
a) there are over five kinds of dopamine receptors which have
been characterized to date, and even
the best researchers know nothing about the D5 subtype
b) there are five separate kinds of cholinergic receptors
c) there are fifteen different kinds of serotonin receptors
d) neuroscientists do not yet understand the relationship between neuroreceptor density, sensitivity, or neurotransmitter turnover
3) the model fails to consider the fact that many of the neurochemicals which are presumed to be the basis of "mental disease" are, in fact, broadly distributed throughout the body. This fact casts doubt about our conceptualization of "brain tissue" (perhaps it is not limited to the cranial vault) and also raises questions about the reliability of serum or urine tests, as those assays may be capturing levels which reflect non-brain locations of neurotransmitter activity
a) over 90% of the serotonin in the human body is made by the enterochromaffin cells of the stomach and small intestine, rather than the raphe nucleus of the midbrain and pons
b) a broad variety of cells in the human body possess receptors for many of the neurotransmitters, including white blood cells and platelets
4) the model fails to acknowledge the impossibility of measuring discrete events in the human brain, due to the speed of neurotransmission; and due to the relative bulk of our measuring devices, relative to the size and complexity of each synapse
5) the model fails to acknowledge the impossibility of explaining the brain in reductionistic terms. That is to say, the organic whole may so far exceed the sum of the component parts, that science will never be able to fully explain the workings of this magnificent system. Part of the problem here is that the brain is never capable of being studied in a vacuum - the system is forever open, due to the conscious, and unconscious, processes of the subject who is being observed. Part of the problem, too, arises from the phenomenon of diaschisis, or non-local effects, through which changes in one part of the brain reflect, and then precipitate, complex cascades of events in multiple locations throughout the nervous system. Thus, it is impossible to speak of serotonin or dopamine without analyzing the interactions of all complex chemicals, peptides, and amino acids upon each other, but far too little research has occurred to study the gestalt of these intercommunications.
The human brain consists of over 100 billion neurons, an equal number of support cells (glia), and dozens of neurotransmitters and neuromodulators, all of which participate in the most intricate network known to man. Superimposed upon this incredible array of cognition, sensation, movement, and imagination is the human will. Biological psychiatry, and its TV commercials, seem to have completely dismissed this essential element of the species. While it has become fashionable to compare the human brain to the elements of a computer - the brain tissue, comprising the hardware; and the neuronal circuits and chemical events, comprising the software - it has become disturbingly acceptable to reject the existence of a third component: the operator, who sits at the keyboard.
Humans are corporeal beings, who record the events of life with electrical and chemical fluctuations of a highly refined nervous system. Unfortunately, the chemical model of mental illness has too often confused association with causation. Worse, still, it has failed the species more fundamentally , by suggesting that fluctuations in brain activity occur randomly, and are ultimately more important than the processes through which the human operator comes to work at the keyboard of such an amazing machine.