Discarding Ideology: The Nature/nurture Endgame

Article excerpt

TOPIC. The concepts and research that underpin our understanding of how the brain is the organ of the mind.

PURPOSE. To describe the dynamic nature of nervous system functioning and development; to discuss how the nervous system changes anatomically throughout the lifespan; to examine the vital role and interaction of genetics and environment; and to discuss the relationship among the brain, neurotransmission, genes, and psychiatric illness.

SOURCES. Published literature.

CONCLUSIONS. The latest research from the neurosciences lays to rest any suggestion that psychiatric illnesses are psychologically induced.

Search terms: Cartesian dualism, nature, nurture, neurobiology

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Despite enormous strides and the virtual explosion in our knowledge about human behavior as a function of the brain and body, authors of nursing texts and articles continue to perpetuate the mind-body dichotomy known as "Cartesian dualism." Discarded concepts of questionable utility, such as Freud's stages of development, continue to clutter our psychiatric-mental health nursing texts, yet discussions of such foundational concepts as neuroplasticity, genetics, and the profound effects that environmental factors can have on the development of the brain have begun to appear only recently in the nursing literature (Boyd, 2002; Mohr, 2002).

This is a rather disconcerting state of affairs for a profession that should be grounded, above all, in science. It is also one to which nursing scholars have repeatedly called our attention (McCabe, 2000; Mohr & Mohr, 2001). It is beyond the scope of this article to analyze the reasons why we, as a subspecialty, cling to the past. Suffice it to reiterate, as others have, that we do so at the peril of becoming extinct. The mind-body debate has been put to rest rather definitively by science. It is abundantly clear that the major conceptual approach of the 21st century to psychiatry has its foundation in molecular biology, and we continue to amass evidence that "mental states" have their representation in brain neuronal anatomy and functioning. A persuasive discussion about the end of Cartesian dualism, and what must replace this perspective in psychiatric nursing, requires us to be conversant with the latest empirical studies of normal development.

This article presents some of the concepts and research that underpin our understanding of how the brain is indeed the organ of the mind. It describes the dynamic nature of nervous system functioning and development, discusses how the nervous system changes anatomically throughout the lifespan, and addresses the vital role and interaction of genetics and environment. It also discusses the relationship among the brain, neurotransmission, genes, and psychiatric illness, and presents evidence from research that should lay to rest suggestions that psychiatric illnesses are "psychologically" induced. As it is not possible to be completely exhaustive on this subject within the constraints of a journal article, the discussion will be necessarily oversimplified. Moreover, research in psychiatry changes our knowledge base rapidly. Some of the concepts discussed in this article may be old news by tomorrow, underscoring the need to remain current.

The Wonderful Human Brain

As the major organ of the nervous system, the brain governs all forms of behavior, which includes the behavior of all major body systems. Moreover, the brain is the starting point for why and how we process all "mental" information--not just cognitive, but interpersonal communications, self-concept, emotional reactivity, personality, learned responses, etc. Research findings have made it abundantly clear that the brain is the organ of the mind, and one of its products is behavior. The brain's production of behavior is roughly analogous to the human heart's pumping of blood or the lung's exchanging of gases. Our brains are what make us human. …