The Origin of the Term Plasticity in the Neurosciences: Ernesto Lugaro and Chemical Synaptic Transmission

The Italian psychiatrist Ernesto Lugaro can be regarded as responsible for introducing the term plasticity into the neurosciences as early as 1906. By this term he meant that throughout life the anatomo-functional relations between neurons can change in an adaptive fashion to enable psychic maturation, learning, and even functional recovery after brain damage. Lugaro’s concept of plasticity was strongly inspired by a neural hypothesis of learning and memory put forward in 1893 by his teacher Eugenio Tanzi. Tanzi postulated that practice and experience promote neuronal growth and shorten the minute spatial gaps between functionally associated neurons, thus facilitating their interactions. In addition to discovering the cerebellar cells known by his name and advancing profound speculations about the functions of the glia, Lugaro lucidly foresaw the chemical nature of Synaptic transmission in the central nervous system, and was the first to propose the usage of the terms “nervous conduction” and “nervous transmission” in their currently accepted meaning.     

Making the brain plastic: early neuroanatomical staining techniques and the pursuit of structural plasticity, 1910-1970

The concept of neuronal plasticity is widely used, but seldom defined in the neurosciences. It can signify many different occurrences, such as structural alterations of axons and dendrites (Cotman & Nadler, 1978), behavioural adaptations (Rosenzweig & Bennett, 1996), or physiological changes in synapse formation (Martin et al., 2000) at different stages of health and disease. Although there is such a wealth of research from many disciplines, the neuroanatomical aspects of plasticity are the focus of this paper. It seeks to illuminate the evolution of different concepts of plasticity concerning the structure and circuitry of the central nervous system (CNS). Early modern morphological research on de- and regeneration phenomena in the 19th- and early 20th-century is well documented. These studies, however, almost exclusively concentrated on the peripheral nervous system (PNS). It was one of the major contributions of Santiago Ramón y Cajal (1852-1934), that he applied the concept of regenerative capacities to the CNS. But the term plasticity seemed to have disappeared for about two decades after his death. The ensuing comeback of the expression may be attributed, at least in part, to new neuroanatomical staining and tracing methods. The pursuit of these techniques will serve as a guidepost through varying approaches in different times: It was the 1950s which seemed to spawn the time for new departures in structural investigations of neuronal plasticity.     

The neurophysiological aspects of Pavlov's theory of higher nervous activity: in honor of the 150th anniversary of Pavlov's birth

Whereas Ivan P. Pavlov (1849-1936) is well-known for his work on classical conditioning, his contribution to neuroscience, particularly his interest in the function of neural centers in the central nervous system, is not as widely known. During the last three decades of his life, Pavlov explored cortical processes by salivary reflex conditioning, a method he used to develop his theory of higher nervous activity. This theory outlined the function of the brain in higher organisms in their interaction with the changing environmental contingencies. As early as 1908, Pavlov outlined a neurophysiological theory as the physiological basis of his theory of higher nervous activity. He maintained that the neural processes of excitation and inhibition irradiate and concentrate among the cortical neural centers. Most of all, he emphasized the plasticity of the cortex in higher organisms' in the Darwinian struggle for existence.     

The Neurophysiological Aspects of Pavlov’s Theory of Higher Nervous Activity: In Honor of the 150th Anniversary of Pavlov’s Birth

Whereas Ivan P. Pavlov (1849-1936) is well-known for his work on classical conditioning, his contribution to neuroscience, particularly his interest in the function of neural centers in the central nervous system, is not as widely known. During the last three decades of his life, Pavlov explored cortical processes by salivary reflex conditioning, a method he used to develop his theory of higher nervous activity. This theory outlined the function of the brain in higher organisms in their interaction with the changing environmental contingencies. As early as 1908, Pavlov outlined a neurophysiological theory as the physiological basis of his theory of higher nervous activity. He maintained that the neural processes of excitation and inhibition irradiate and concentrate among the cortical neural centers. Most of all, he emphasized the plasticity of the cortex in higher organisms’ in the Darwinian struggle for existence.     

Making the Brain Plastic: Early Neuroanatomical Staining Techniques and the Pursuit of Structural Plasticity, 1910–1970

The concept of neuronal plasticity is widely used, but seldom defined in the neurosciences. It can signify many different occurrences, such as structural alterations of axons and dendrites (Cotman & Nadler, 1978), behavioural adaptations (Rosenzweig & Bennett, 1996), or physiological changes in synapse formation (Martin et al., 2000) at different stages of health and disease. Although there is such a wealth of research from many disciplines, the neuroanatomical aspects of plasticity are the focus of this paper. It seeks to illuminate the evolution of different concepts of plasticity concerning the structure and circuitry of the central nervous system (CNS). Early modern morphological research on de- and regeneration phenomena in the 19th- and early 20th-century is well documented. These studies, however, almost exclusively concentrated on the peripheral nervous system (PNS). It was one of the major contributions of Santiago Ramón y Cajal (1852–1934), that he applied the concept of regenerative capacities to the CNS. But the term plasticity seemed to have disappeared for about two decades after his death. The ensuing comeback of the expression may be attributed, at least in part, to new neuroanatomical staining and tracing methods. The pursuit of these techniques will serve as a guidepost through varying approaches in different times: It was the 1950s which seemed to spawn the time for new departures in structural investigations of neuronal plasticity.     

David Hartley's psychobiological associationism and the legacy of Aristotle

The idea that there are certain "laws" of learning (similarity, contrast, contiguity) can be traced to Aristotle. He maintained that external stimuli cause small movements in the vessels to the dominant heart, the vestiges of which can be linked to one another. Aristotle's laws of learning were incorporated into the writings of Hobbes, Locke, and Berkeley, men who said nothing about the physiological correlates of mental associations. This left the door open for David Hartley to combine mental associationism with the Newtonian idea that sensations can cause minute particle vibrations in the nerves. Hartley's amalgam of psychology, philosophy, and neurology was first presented in 1746, as a "trial balloon" at the end a little-known monograph on a treatment for kidney stones. It was repeated three years later in his better-known Observations on Man. In many ways, modern psychobiological connectionism can be traced back to Hartley's Conjectures of 1746, in which Aristotle's original thoughts were modified with then current ideas about functions of the mind and the nervous system.     

The impossible interview with the man of the neuron doctrine. Interview by Edward G Jones

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.     

The impossible interview with the man of the hidden biological structures. Interview by Paolo Mazzarello

This paper presents an "impossible interview" to Professor Camillo Golgi, placed in time in December 1906. The Italian Professor Golgi from Pavia has been awarded the Nobel Prize for Physiology or Medicine ex aequo with the Spanish anatomist Santiago Ramón y Cajal. Both scientists have obtained the award for their work on the anatomy of the nervous system. However, they have opposite views on the mechanisms underlying nervous functions. Golgi believes that the axons stained by his "black reaction" form a continuous anatomical or functional network along which nervous impulses propagate. Ramón y Cajal is the paladin of the neuron theory, a hypothesis questioned by Golgi in his Nobel lecture of Tuesday, December 11. After the ceremony, an independent journalist has interviewed Professor Golgi in the Grand Hotel in Stockholm. Excerpts about his education, his main scientific discoveries, and his personal life are here given (reconstructing the "impossible interview" on the basis of Golgi's original writings).     

Ralph Cudworth and the theological origins of consciousness

The English Neoplatonic philosopher Ralph Cudworth introduced the term "consciousness" into the English philosophical lexicon. Cudworth uses the term to define the form and structure of cognitive acts, including acts of freewill. In this article I highlight the important role of theological disputes over the place and extent of human freewill within an overarching system of providence. Cudworth's intellectual development can be understood in the main as an increasingly detailed and nuanced reaction to the strict voluntarist Calvinism that is typified in the thought of his near contemporary William Perkins. At the heart of Cudworth's rejection of Calvinism is the dilemma over whether God is understood primarily in terms of will or justice. In this fleshing-out of the power of consciousness Cudworth moves from an instrumental account of the working of the human mind towards an account of human consciousness that is intrinsic to his definition of human agency.     

Mesoglia & microglia--a historical review of the concept of mononuclear phagocytes within the central nervous system

More than a century and a half has elapsed since the first accounts of mesodermal phagocytic elements were proposed within the central nervous system. Over the intervening decades, body and substance were added to this concept through the advancement of histological techniques at the disposal of the researcher and the acute and keen-minded skills of the pathologist. Notable among these pioneering efforts were the contributions of W. Ford Robertson, Santiago Ramon y Cajal, Pio del Rio-Hortega and Wilder Penfield amongst an entire cavalcade of other noteworthy figures. The term 'mesoglia' and 'third element of the nervous system' was bestowed upon these cells towards the beginning of the twentieth century to account for their separate origins from neurons and macroglia. It was later amended by del Rio-Hortega in 1919, to 'microglia' in order to further discriminate between true mesodermal elements and oligodendrocytes, previously regarded as a component of 'mesoglia'. This particular contention sparked much controversy among del Rio-Hortega's peers and resulted in an escalation of fruitful research throughout Europe that eventually declined up to the outbreak of the Second World War. The post-war years were a period of the 'dark ages' that cast doubt on the very existence and nature of microglia, until the 'renaissance' of research was once again rejuvenated in the 1960s, by a new cohort of intrigued minds: Cammermeyer, Blinzinger, Kreutzberg and others who saw in the 'third element' the potential that is now commonly ascribed to microglia: the intrinsic immune effector cells of the CNS. It is now universally accepted that microglia are involved as the first line of rapid defence in any pathology of the nervous system, and as such, present a diagnostic tool for the neuropathologist. Although our knowledge of microglia stems from an extensive body of work conducted over the last two decades, much of the earlier work (pre-1960s) has remained somewhat obscure. This is partly accountable due to the limited availability of translated works, and additionally to the lack of a compendium of these articles. This paper will present a comprehensive overview of the pioneering research on mononuclear phagocytes within the central nervous system, which has direct bearing on our present-day understanding of the concept of microglia.     

近代日本文学家的“东力学”——以芥川龙之介为中心

美国著名文学批评家爱德华·W·萨义德在《东方学》一书中提出了在西方实际上一直存在着与“先进的西方”相对的“落后的东方”,也就是所谓的“东方学”式的“二元对立”思维方式。它在西方国家以东方国家为对象大力推进殖民政策的过程中,已成为一种霸权话语。日本是一个东方国家,但是它在比西方国家落后几十年的状态下学习西方,并发展到以中国大陆为主要对象推进殖民政策。从日本近代文学家当时关于中国的言论当中也可以看出有类似于萨义德提出的“东方学”的思维方式。因篇幅的关系,本文试图通过借鉴萨义德在《东方学》里所提出的观点,重点围绕芥川龙之介这位作家,深入探讨他对中国的一些言论。     

Georges Sorel’s Diremption: Hegel,Marxism and Anti-Dialectics

Georges Sorel’s use of the term diremption to describe his method has long been found obscure. This paper shows that the term was associated with Hegel, and that interpreting it in this light can help us make sense of Sorel's method. Sorel, this is to say, in his revision of Marxism and his social theory more generally, was engaging specifically with Hegelian philosophy. In addition to clarifying Sorel's method, this perspective allows us both to place Sorel more clearly in his fin-de-siècle context and to draw connections between his work and more recent marxisant theory.     

'Old Paris Is No More': Geographies of Spectacle and Anti-Spectacle

The term 'spectacle' has played an important role in recentcritical discussions of vision and visuality. In human geography it has often been used to designate new forms of capitalist urban development associated with display and show. This paper examines aspects of the term by addressing the critique of the spectacle developed by the situationist Guy Debord. It situates his writings on the subject back into the context of his engagements with the modern city between the 1950s and 1970s, especially in Paris, where hespent much of his life. In particular, it reads these writings in terms both of his bleak view of urban change and alienation under capitalism and of the 'glimmers of light' that he found in 'the setting sun of this city.' Debord's attachment to certain urban sites within this critique of urban spectacle was often nostalgic. Yet it can also be understood as part of his concern with challenging the ways in which urban spaces were being reconstructed, and as opening up gaps or cracks for thinking about 'counter-sites' and points of political intervention.     

杨端六与罗素——从罗素长沙讲学说起

五四时期英国哲学家罗素来华讲学,以其大哲学家的眼光,就中国问题发表看法,激起中国思想学术界颇大的反响。从英伦学成而归的杨端六,是罗素在上海、长沙讲学期间的一位重要译员。针对国人盲目追崇的学风,杨端六在报章上发表批评文章,主张应该理性地对待罗素及其他西方哲人的学说。他本人亦从罗素实用哲学中吸取精神养料,进行着社会政治实践。杨端六与罗素的思想交往,以往鲜有人讨论,但不失为这次中西文化交流中的一缕理性之光。