The Gap in Genetic–Environmental Studies of Psychopathology

Doubtless the genetic studies reviewed in the October 2015 Observer article “Passing Down Psychopathology” are providing important biological links to the roots of psychopathology in children. They do, however, as the article points out, “explain very small amounts of variance, suggesting that researchers have yet to identify many of the key factors explaining developmental variation.” The theoretical approaches of genome-wide association studies are also deemed to conflict with the main theoretical approaches in developmental psychopathology. We might hope that the role of the genes, with advances in methodology, will be better explained over the years to come. At present, however, those concerned with causes and treatment of psychopathology will have to rely mainly on empirical studies and analysis of the environmental factors that shape it.

In this respect, I believe there is a “blind spot” in psychology as a discipline that underlies its avoidance of recent lessons emanating from the now highly developed knowledge of the role of neurochemistry in mental disorders. The effectiveness of new drugs has led to identifying neurochemical dysfunction as a major source of severe psychopathologic behavior. Essentially, it has been uncovered over the last several decades that certain monoamine neurotransmitters are involved in regulating specific behaviors that are further associated with psychopathology — notably, the serotonergic and noradrenergic systems. The serotonergic system, for example, is associated rather directly with “impulsive aggression” and anxiety; the noradrenergic system is associated with motor activity and depressed mood (see Morilak & Frazer, 2004, for a review of the basic research). Dysfunction in these systems is shown to be directly reduced through treatment with drugs selective for inhibiting the reuptake of these neurotransmitters into the central nervous system — drugs such as fluoxetine, an SSRI, and desipramine, a selective noradrenergic drug (further details on the background research are in Katz, 2013).

This new pathway to influencing psychopathology suggests that a strong direction for current research should be a focus on the links among genes, specific neurotransmitter systems, and specific dysfunctional behaviors such as anxiety and aggression — research that would run counter to attempts to prematurely link neurochemical factors to diagnostic entities. The recommendation is that neurochemistry, already demonstrated to be associated with specific psychopathological behaviors, be studied to help erase the “gap” between genetic and environmental factors and provide the essential links to facilitate the pace of research in this sphere.

-Martin M. Katz

References

Katz, M. M. (2013). Depression and drugs: The neurobehavioral structure of a psychological storm.  New York, NY: Springer.

Morilak, D. A., & Frazer, A. (2004). Antidepressants and brain monoaminergic systems: A dimensional approach to understanding their behavioural effects in depression and anxiety disorders. International Journal of Neuropsychopharmacology, 7, 193–218.