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Scientific reductionism, the view that higher level functions can be explained by properties at some lower-level or levels, has been an assumption of nervous system analyses since the acceptance of the neuron doctrine in the late 19th century, and became a dominant experimental approach with the development of intracellular recording techniques in the mid-20th century. Subsequent refinements of electrophysiological approaches and the continual development of molecular and genetic techniques have promoted a focus on molecular and cellular mechanisms in experimental analyses and explanations of sensory, motor, and cognitive functions. Reductionist assumptions have also influenced our views of the etiology and treatment of psychopathologies, and have more recently led to claims that we can, or even should, pharmacologically enhance the normal brain. Reductionism remains an area of active debate in the philosophy of science. In neuroscience and psychology, the debate typically focuses on the mind-brain question and the mechanisms of cognition, and how or if they can be explained in neurobiological terms. However, these debates are affected by the complexity of the phenomena being considered and the difficulty of obtaining the necessary neurobiological detail. We can instead ask whether features identified in neurobiological analyses of simpler aspects in simpler nervous systems support current molecular and cellular approaches to explaining systems or behaviors. While my view is that they do not, this does not invite the opposing view prevalent in dichotomous thinking that molecular and cellular detail is irrelevant and we should focus on computations or representations. We instead need to consider how to address the long-standing dilemma of how a nervous system that ostensibly functions through discrete cell to cell communication can generate population effects across multiple spatial and temporal scales to generate behavior. [ABSTRACT FROM AUTHOR]

Camillo Golgi was an extraordinary scientist whose contributions in the domain of neuroanatomy proved to be critical for emergence of neuroscience as a sovereign scientific discipline. Golgi's invention of the Black Reaction (La reazione nera) was a watershed event as it allowed remarkable visualization of the organizational pattern of elements of nervous system among complex puzzle of close knit interconnections. Till this time thin filamentary extensions of neural cells (axon and dendrites) could not be visualized with available staining techniques because of their slender and transparent nature. However invention of Black Reaction and its subsequent application demystified the basic architecture of brain tissue which was now visible to the scholars in all its complexity in microscopic studies. Golgi is also credited with the discovery of two types of sensory receptors in muscle tendons: Golgi tendon organ and Golgi-Mazzoni corpuscles. Golgi was the first to be successful in staining myelin component of axon, which he used to discover the myelin annular apparatus. He identified the complete life cycle of Plasmodium (malarial parasite) in human erythrocytes. His research on histological details of human kidney highlighted the existence of juxtaglomerular apparatus. Later on Spanish scientist Santiago Ramón y Cajal, based on the use of Golgi's Staining (Black Reaction) documented the morphologic details of nervous system in a more refined manner, which eventually led to the emergence of Neuron Doctrine. In recognition of their exemplary contributions in neuroscience Golgi and Cajal were jointly awarded the Nobel Prize for Physiology or Medicine in 1906. [ABSTRACT FROM AUTHOR]

Over the years the field of neuroanatomy has evolved considerably but unraveling the extraordinary structural and functional complexity of the brain seems to be an unattainable goal, partly due to the fact that it is only possible to obtain an imprecise connection matrix of the brain. The reasons why reaching such a goal appears almost impossible to date is discussed here, together with suggestions of how we could overcome this anatomical problem by establishing new methodologies to study the brain and by promoting interdisciplinary collaboration. Generating a realistic computational model seems to be the solution rather than attempting tofully reconstruct the whole brain or a particular brain region. [ABSTRACT FROM AUTHOR]

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Dendritic spines are key components of a variety of microcircuits and they represent the majority of postsynaptic targets of glutamatergic axon terminals in the brain. The present article will focus on the discovery of dendritic spines, which was possible thanks to the application of the Golgi technique to the study of the nervous system, and will also explore the early interpretation of these elements. This discovery represents an interesting chapter in the history of neuroscience as it shows us that progress in the study of the structure of the nervous system is based not only on the emergence of new techniques but also on our ability to exploit the methods already available and correctly interpret their microscopic images. [ABSTRACT FROM AUTHOR]

In 1873 Camillo Golgi discovered his eponymous stain, which he called la reazione nera. By adding to it the concepts of the Neuron Doctrine and the Law of Dynamic Polarisation, Santiago Ramon y Cajal was able to link the individual Golgi-stained neurons he saw down his microscope into circuits. This was revolutionary and we have all followed Cajal's winning strategy for over a century. We are now on the verge of a new revolution, which offers the prize of a far more comprehensive description of neural circuits and their operation. The hope is that we will exploit the power of computer vision algorithms and modern molecular biological techniques to acquire rapidly reconstructions of single neurons and synaptic circuits, and to control the function of selected types of neurons. Only one item is now conspicuous by its absence: the 21st century equivalent of the concepts of the Neuron Doctrine and the Law of Dynamic Polarisation. Without their equivalent we will inevitably struggle to make sense of our 21st century observations within the 19th and 20th century conceptual framework we have inherited. [ABSTRACT FROM AUTHOR]

Robert Bentley Todd, who is best remembered for 'Todd's paralysis,' made many more important contributions to neurology and neuroscience, including the concept of brain electricity and electrical discharges in epilepsy. He was also a pioneering microscopist and we here review his neurohistological studies and his contributions to the application of Schwann's (1839) cell theory to the nervous system and the later neuron doctrine, as described in his textbook The Descriptive and Physiological Anatomy of the Brain, Spinal Cord and Ganglions (Todd, 1845), his Cyclopaedia of Anatomy and Physiology (1847) and his joint textbook with William Bowman The Physiological Anatomy and Physiology of Man (1845). Writing in the mid-1840s, Todd acknowledged that the 'vesicles' he observed corresponded to the earlier descriptions of 'globules' or 'kugeln' by Valentin and which Schwann first interpreted as cell bodies. Todd was among the first to recognize that nerve cell bodies were in continuity with axons ('axis cylinders'), sometimes associated with 'the white substance of Schwann' ('tubular' fibers), or sometimes without ('gelatinous' fibers). He also described continuous nerve cell branching processes, later called dendrites. He was the first to recognize the insulating properties of Schwann's 'white substance' (myelin) to facilitate conduction. Influenced by his contemporary, Faraday, Todd was also the first to develop the functional concept of dynamic polarization ('nervous polarity') to explain nerve cell conduction. [ABSTRACT FROM AUTHOR]

The twentieth century has witnessed many outstanding scientists who revolutionized our understanding of Nature. Our comprehension of the brain to a large extent stems from the meticulous work of the Spanish biologist Santiago Ramón y Cajal, who is considered as the Father of Modern Neurosciences. Cajal made prolific contributions for over half a century on the anatomical organization of the brain. The Royal Academy of Sciences of Berlin awarded Cajal the prestigious Helmholtz gold medal for his contributions in the year 1905. He was awarded the Nobel Prize in Physiology or Medicine in 1906 along with Camillo Golgi (an Italian scientist) in recognition of his work on the structure of the nervous system. In this article we will remember the life and work of this brilliant scientist. [ABSTRACT FROM AUTHOR]

This paper follows the form of that by Mazzarello that precedes it (Mazzarello, 2006) and presents an imaginary interview with Santiago Ramón y Cajal in December 1906. A few days earlier Cajal had been awarded the Nobel Prize for Physiology or Medicine, an award that he shared equally with Professor Camillo Golgi. Golgi had been recognized for his work as a pioneer into investigations of the nervous system, primarily on account of his discovery of the "black reaction" of silver chromate impregnation of whole nerve cells and their processes. Cajal had been recognized for his implementation of that method and for laying with it the foundations of what was to become modern neuroanatomical science. Paradoxically, the two awardees had been led by their researches to diametrically opposed views of the organization of the nervous system. Golgi believed in a continuous network of axons that formed the basis of all the integrative properties of the nervous system, while Cajal had provided the information that led to the formulation of the neuron doctrine that saw the nervous system as being made up of chains of discontinuous cells joined by polarized functional contacts that we now call synapses. The paper takes the form of an interview with Professor Cajal in the Grand Hotel Stockholm. His responses to questions posed by the imaginary interviewer are all taken from Cajal's own writings. [ABSTRACT FROM AUTHOR]

The year 2000 marks the 150th anniversary of the birth of Edward Albert Schäfer (Sir Edward Albert Sharpey-Schafer). Affiliated first with University College, London, and then with Edinburgh University, Schäfer made monumental contributions to the fields of histology, physiology, endocrinology, and practical medicine. This paper traces his professional life and emphasizes his seminal contributions to the neurosciences, which include his findings in support of neuron doctrine, his research on cortical localization in monkeys, his discovery of adrenaline and its place in the history of neural transmission, and his studies on recovery after nerve damage. Author of many histology and physiology books, founder of the “Quarterly Journal of Experimental Physiology,” and mentor to many students who achieved great fame themselves, Schäfer was an active teacher and researcher, a man who remained committed to his vision of medicine based on laboratory science until he died in 1935. [ABSTRACT FROM AUTHOR]