Nothing in the brain makes sense except in the light of structure, to paraphrase the celebrated biologist, Theodosius Dobzhansky, who was speaking of evolution, a process that ultimately led to the genesis of this extraordinary organ.
Accordingly, “Insights into the Brain”, a gentle play on words, is devoted to the structure of the human brain and offers a concise yet striking visual introduction into its complexity and beauty at the cellular and circuit level. It has no major medical or scientific pretentions, no claims to be comprehensive, and no profound message. Nonetheless, inspection of these images should enhance our appreciation of the diversity of those interacting elements which collectively comprise our brains and which ultimately yield
consciousness, mind, language, cognition, and other complex, emergent functions.
Interaction is very much the operative word since the brain is a complex system composed, as amply depicted herein, by networks of neurons and networks in neurons. Appreciation of this facet of brain structure has profoundly enhanced our understanding of its dynamic organization and function.
Nonetheless, the brain still conceals many mysteries, such as: the nature of the interface between cerebral circuits and mind; precisely how genes and environment interact throughout life to yield unique adult phenotypes like you and me; how best to preserve cerebral homeostasis (mental health); and how to restore it when perturbed. These are challenges for our 21st century in much the same way as the deciphering of its core structure was a mission for our predecessors in the 20th. Success in this venture will depend on the intensive pursuit of basic research in the field of neuroscience, and on the further development of sophisticated techniques for studying structure like: fluorescent light microscopy (individual cells and their substructures); magnetic resonance imaging (brain regional structure) and diffusion tensor imaging (fiber projections). These methodologies generated many of the stunning images shown herein.
While not specifically depicted in this document, the delicacy and refinement of the images hint at the vulnerability of the brain to potential disruption. Indeed, like all complex networks (including the eponymous brain coral of tropical seas), the highly resilient human brain is nonetheless susceptible to multiple, sustained, and uncontrolled “stressors.” Destruction of coral reefs and other ecosystems negatively impacts the well-being of humanity, while exposure of individuals to adverse genetic, developmental, and environmental risk factors perturbs the cells and circuits depicted herein to trigger disorders of mental health. Correspondingly, avoidance of impending disruption by the use of early-warning signs (biomarkers) is a core objective of current research. In addition, efforts are being made to find therapies that normalize brain function and reinstate the equilibrium of cerebral networks.
To conclude, improved knowledge of the structure and neurobiological substrates of the brain, in health and in disease, provides a foundation for progress towards the more effective treatment and prevention of psychiatric and neurological disorders.
Professor Dr Mark J. MILLAN, BA, MA, PhD (Cantab)