This compilation brings together 20 essays of Santiago Ramón y Cajal (1852-1934), the neuroscientist par excellence and 1906 Nobel Laureate in Medicine, on topics beyond neuroanatomy, most appearing in English for the first time. The annotated collection makes available in one handy volume Cajal's ideas on psychology, art and education, still current and still relevant, derived from his books La Psicología de los Artistas, Charlas de Café, El Mundo Visto a los Ochenta Años, Pensamientos Pedagógicos and Escritos Inéditos. (...) An acute observer of the intellectual and social scene of the avant-garde, Cajal emerged in 20th-century Spain in a further role as a philosopher and educator. The contents bespeak Cajal's inquiry into the varieties of human experience and shed new light on the breadth of his genius, imagination and passion, helping us to rethink what we thought we already understood about Don Santiago's own mind. (shrink)

Machine generated contents note: Cajal and Consciousness: Introduction. By PEDRO C. MARIJUAN1 -- Part I. Consciousness, One Hundred Years after Textura -- Progress in the Neural Sciences in the Century after Cajal (and the Mysteries -- That Remain). By THOMAS D. ALBRIGHT, THOMAS M. JESSELL, -- ERIC R. KANDEL, AND MICHAEL I. POSNER11 -- Part II. Biological Complexity and the Emergence of Consciousness -- Consciousness, Reduction, and Emergence: Some Remarks. -- By MURRAY GELL-MANN41 -- The Epistemic Paradox of (...) Mind and Matter. By HAROLD J. MOROWITZ50 -- The Conscious Cell. BY LYNN MARGULIS55 -- Complexity and Tinkering. By FRANCOIS JACOB71 -- Consciousness, the Brain, and Spacetime Geometry. By STUART HAMEROFF. 74 -- Consciousness, the Brain, and Spacetime Geometry: An Addendum-Some -- New Developments on the Orch OR Model for Consciousness. -- By ROGER PENROSE105 -- Part III. From Primary to Higher-level Consciousness -- Consciousness: The Remembered Present. By GERALD EDELMAN111 -- Consciousness and the Binding Problem. By WOLF SINGER123 -- Cajal on Neurons, Molecules, and Consciousness. By JEAN-PIERRE CHANGEUX 147 -- A Neuronal Model of a Global Workspace in Effortful Cognitive Tasks. By -- STANISLAS DEHAENE, MICHEL KERSZBERG, AND JEAN-PIERRE -- CHANGEUX152 -- Consciousness and the Brain: The Thalamocortical Dialogue in Health and -- Disease. By RODOLFO LLINAS AND URS RIBARY166 -- The Neuroanatomy of Phenomenal Vision: A Psychological Perspective. -- ByPETRA STOERIG176 -- Co-evolution of Human Consciousness and Language. By MICHAEL A. ARBIB 195 -- From Computing with Numbers to Computing with Words-From -- Manipulation of Measurements to Manipulations of Perceptions. -- By LOTFI A. ZADEH221 -- Part IV. Closing Remarks -- Who Was Cajal? By ALBERTO PORTERA-SANCHEZ253 -- Index of Contributors259 -- Subject Index261. (shrink)

Santiago Ramón y Cajal, the primary architect of the neuron doctrine and the law of dynamic polarization, is considered to be the founder of modern neuroscience. At the same time, many philosophers, historians, and neuroscientists agree that modern neuroscience embodies a mechanistic perspective on the explanation of the nervous system. In this paper, I review the extant mechanistic interpretation of Cajal’s contribution to modern neuroscience. Then, I argue that the extant mechanistic interpretation fails to capture the explanatory import (...) of Cajal’s law of dynamic polarization. My claim is that the definitive formulation of Cajal’s law of dynamic polarization, despite its mechanistic inaccuracies, embodies a non-mechanistic pattern of reasoning (i.e., design explanation) that is an integral component of modern neuroscience. (shrink)

Nuclear bodies contribute to non‐random organization of the human genome and nuclear function. Using a major prototypical nuclear body, the Cajal body, as an example, we suggest that these structures assemble at specific gene loci located across the genome as a result of high transcriptional activity. Subsequently, target genes are physically clustered in close proximity in Cajal body‐containing cells. However, Cajal bodies are observed in only a limited number of human cell types, including neuronal and cancer cells. (...) Ultimately, Cajal body depletion perturbs splicing kinetics by reducing target small nuclear RNA (snRNA) transcription and limiting the levels of spliceosomal snRNPs, including their modification and turnover following each round of RNA splicing. As such, Cajal bodies are capable of shaping the chromatin interaction landscape and the transcriptome by influencing spliceosome kinetics. Future studies should concentrate on characterizing the direct influence of Cajal bodies upon snRNA gene transcriptional dynamics.Also see the video abstract here. (shrink)

This study presents abundant empirical evidence to sustain that the genius of Santiago Ramón y Cajal was the result of a conscious effort of self-construction, the key factors of which were psychosocial, some of which are also found in other highly creative scientists. In this case, new factors appear that have not been observed in other geniuses, such as a substantial vicarious and self-regulating capacity and a high degree of perceived self-efficacy. The procedure used is the narrative analysis of (...) essentially autobiographic texts. The theoretical framework on which the study is based is the psychology of science and Bandura cognitive-social theory. (shrink)

[M]y attention was drawn to the flower garden of the grey matter, which contained cells with delicate and elegant forms, the mysterious butterflies of the soul, the beating of whose wings may someday... clarify the secret of mental life. Art can actually facilitate scientific understanding, even discovery. Art can be, and has been, the entryway to vision and the understanding of natural phenomena as demonstrated in its role in the development of neuron theory. While developing a course on current brain (...) research and learning and then projects for S.T.E.A.M. curriculum, I was repeatedly drawn to the work of Santiago Ramon y Cajal, whose life work provides an extraordinary example of the.. (shrink)

Se intenta poner de manifiesto, en este artículo, a través de un somero análisis de la biografía y de la obra de Santiago Ramón y Cajal, como su contribución a la historia de la histología no fue un fruto del azar, sino de una profunda investigación propiciada por su deseo de saber.

It is now clear that two prominent nuclear domains, interchromatin granule clusters (IGCs) and Cajal bodies (CBs), contribute to the highly ordered organization of the extrachromosomal space of the cell nucleus. These functional domains represent structurally stable but highly dynamic nuclear organelles enriched in factors that are required for different nuclear activities, especially RNA biogenesis. IGCs are considered to be the main sites for storage, assembly, and/or recycling of the essential spliceosome components. CBs are involved in the biogenesis of (...) several classes of small RNPs as well as the modification of newly assembled small nuclear RNA. We have summarized data on the molecular composition, structure, and functional roles of IGCs and CBs in the nuclei of mammalian somatic cells and oocytes of some animals with a special focus on insects. We have focused on similarities and differences between the IGCs and CBs of oocytes and the well‐studied CBs and IGCs of cultured mammalian somatic cells. We have shown the heterogeneous character of oocyte IGCs and CBs, both in structure and molecular content. We have also demonstrated the unique capacity of oocytes to form close structural interactions between IGC and CB components. We proposed to consider these joint structures as integrated entities, sharing the features of both IGCs and CBs. (shrink)

En este trabajo sostengo que la concepción mecanicista no captura la relevancia explicativa de la ley de polarización dinámica de Cajal. La relevancia explicativa de la ley se fundamenta en su rol como principio de diseño neuronal. Como tal, la ley nos brinda acceso epistémico a intervenciones ideales, conceptualmente posibles, sobre la localización de los diversos componentes de los centros nerviosos, y nos permiten evaluar el impacto de esas intervenciones sobre las condiciones de viabilidad del organismo.

Mediator is a coregulatory complex that plays essential roles in multiple processes of transcription regulation. One of the human Mediator subunits, MED26, has a role in recruitment of the super elongation complex (SEC) to polyadenylated genes and little elongation complex (LEC) to non‐polyadenylated genes, including small nuclear RNAs (snRNAs) and replication‐dependent histone (RDH) genes. MED26‐containing Mediator plays a role in 3′ Pol II pausing at the proximal region of transcript end sites in RDH genes through recruitment of Cajal bodies (...) (CBs) to histone locus bodies (HLBs). This finding suggests that Mediator is involved in the association of CBs with HLBs to facilitate 3′ Pol II pausing and subsequent 3′‐end processing by supplying 3′‐end processing factors from CBs. Thus, we argue the possibility that Mediator is involved in the organization of nuclear bodies to orchestrate multiple processes of gene transcription. (shrink)

In his work, Michael Ruse underscores the significance of metaphors in science, with a particular focus on the “abyss” between mechanistic and organicist metaphors in the history and practice of biology. Ruse posits that the Darwinian revolution involved a radical “metaphor shift” in biology, transitioning from organicism to mechanism. In this article, I set out several objectives (i) to assess whether the neuronist revolution, pivotal in the inception of neuroscience, involved a shift from an organicist metaphor to a mechanistic one; (...) (ii) to highlight the indispensable influences of organicist metaphors in Cajal’s neuron doctrine; and, consequently, (iii) to challenge the idea of an abyss between mechanistic and organicist metaphors, at least, in neuroscience. (shrink)

In the beginning of the 20th century the groundbreaking work of Ramon y Cajal firmly established the neuron doctrine, according to which neurons are the basic structural and functional units of the nervous system. Von Weldeyer coined the term “neuron” in 1891, but the huge leap forward in neuroscience was due to Cajal’s meticulous microscopic observations of brain sections stained with an improved version of Golgi’s la reazione nera (black reaction). The latter improvement of Golgi’s technique made it (...) possible to visualize the arborizations of single neurons that were “colored brownish black even to their finest branchlets, standing out with unsurpassable clarity upon a transparent yellow background. All was sharp as a sketch with Chinese ink”. The high quality of both the visualization of individual nerve cells and the work performed on studying the anatomy of the central nervous system lead Ramon y Cajal to the conclusion that axons output the nervous impulses to the dendrites or the soma of other target neurons. (shrink)

Since the growth cone was first described a century ago by Cajal, considerable effort has been directed towards understanding the mechanisms responsible for its guidance. Traditionally, attention has focussed on the role of adhesive molecules in determining neural development. Recently, it has become apparent that inhibitory interactions may play a crucial part in axonal navigation. A common feature of inhibition seen in three model systems (peripheral nerve segmentation, retinotectal mapping and CNS/PNS segregation) is a collapse of the motile structures (...) of the growth cone. It is increasingly clear that the identification of molecular mechanisms of inhibition, as well as those of adhesion, will be of fundamental importance to understanding neural development. (shrink)

Love, fear, hope, calculus, and game shows-how do all these spring from a few delicate pounds of meat? Neurophysiologist Ian Glynn lays the foundation for answering this question in his expansive An Anatomy of Thought, but stops short of committing to one particular theory. The book is a pleasant challenge, presenting the reader with the latest research and thinking about neuroscience and how it relates to various models of consciousness. Combining the aim of a textbook with the style of a (...) popularization, it provides all the lay reader needs to know to participate in the philosophical debate that is redefining our attitudes about our minds. Drawing on the rich history of neurological case studies, Glynn picks through the building blocks of our nervous system, examines our visual and linguistic systems, and probes deeply into our higher thought processes. The stories of great scientists, like Ramon y Cajal, and famous patients, like Sperry's split-brained epileptics, illuminate the scientific issues Glynn selects as essential for understanding consciousness. Some might argue that his lengthy explorations of natural selection overemphasize evolutionary explanations of psychological phenomena, but they must also agree that evolutionary psychology has distanced itself mightily from social Darwinism in recent years and merits a reappraisal. The great consciousness debate may form the core of the 21st-century Zeitgeist; get ready for it with An Anatomy of Thought. -Rob Lightner From Publishers Weekly How do we know? What do we think? How could a philosophical problem-'the mind-body problem,' say-induce a headache? What can evolutionary theory, molecular biology, the history of medicine and experimental psychology tell us about the features of human consciousness, and (once again) how do we know? Glynn, a physician and Cambridge University professor, meticulously attempts to answer these questions and more, setting forth the results of all sorts of research relevant to our brains-from 19th-century dissections to Oliver Sacks-like case studies, work with monkeys and supercomputers, and the enduring puzzles of philosophy, which he rightly saves for near the end. After explaining evolution by natural selection and 'clearing away much dross,' Glynn lays out the experiments and theories that have shown 'how nerve cells can carry information about the body, how they can interact' and how sense organs work; demonstrates the 'mixture of parallel and hierarchical organization' in our brains and 'the striking localization of function within it'; considers where neuroscience is likely to go; and admits that, among the many fields of exciting research just ahead, 'we can be least confident of progress toward a complete, scientific explanation of our sensations and thoughts and feelings.' Other recent explaining-the-brain books have sometimes advanced simplistic, or implausibly grand, claims about the nature and features of consciousness in general. Instead, Glynn offers a patient, informative, well-laid-out researcher's-eye view of what we have learned, how we figured it out and what we still don't know about neurons, senses, feelings, brains and minds. (Apr.) Copyright 2000 Reed Business Information, Inc. From Library Journal The nature of consciousness, which perennially troubles the minds of scientists and philosophers, is the subject of an ever-growing body of literature. Two of the latest entries approach the topic from different perspectives. Glynn, a professor of physiology and head of the Physiological Laboratory at Cambridge, offers a comprehensive summary of what we know about the brain-both its evolution and its mechanisms. Among the topics he covers are natural selection, molecular evolution, nerves and the nervous system, sensory perception, and the specific structures responsible for our intellect. Using the mechanisms involved in vision and speech as models, Glynn skillfully describes various neurological deficiencies that can lead to 'disordered seeing' and problems with the use of language. He carefully distinguishes what we know through experimental evidence from what we know through the observation of patients with neurological damage. He also describes some of the major theories that attempt to explain why these structures arose. While his book concentrates on the structures that make up the mind, Glynn is well aware that some physical events appear explicable only in terms of conscious mental events-a situation that conflicts with the laws of modern physics. Only briefly, however, does he consider the various approaches that have been taken to deal with the issues of mind/body and free will. In contrast, this is the primary focus of The Physics of Consciousness. After reviewing the fundamentals of classic physics, Walker (who has a Ph.D. in physics) summarizes elements of the new physics in which our knowledge of space, time, matter, and energy are all dependent on the moment of observation. Walker explores the meaning of consciousness as a characteristic of the observer. In this context both the observer and the act of measurement are critical. In essence, Walker leads his reader on a journey through his concept of a 'quantum mind,' which can both affect matter (including other minds) and can be affected by other distant matter/minds. To break up what would otherwise be an extremely dense text, Walker also relates the very touching story of the loss of his high-school sweetheart to leukemia. Indeed, it is his memory of their relationship that drives Walker to seek an understanding of ultimate reality. At times, he has a tendency to be dogmatic-as when he concludes, 'our consciousness, our mind, and the will of God are the same mind.' While An Anatomy of Thought is appropriate for most academic libraries, the Physics of Consciousness will be most accessible to readers with some knowledge of advanced physics. -Laurie Bartolini, Illinois State Lib., Springfield Copyright 2000 Reed Business Information, Inc. From Booklist The codiscoverers of natural selection-Charles Darwin and Alfred Wallace-disagreed over the possibility of finding an evolutionary explanation for the human mind. Glynn here argues Darwin's side of the debate, tracing an eons-long path of development starting from simple amino acids floating in primal seas and extending through the erect hominids in which the powers of a massive brain first manifest themselves. Patiently adducing evidence of an evolutionary origin for the underlying molecular machinery, Glynn dissects the nerve centers that make possible speech and hearing, sight, and reading. Pressing deeper, he lays bare the cortical foundations of personality. But those who deal with the mind must attend also to the arguments advanced by philosophers. And it is when he turns from dendrites to syllogisms (especially the vexing mind-body paradox) that Glynn's empirical reasoning fails him. In the end, he concedes his perplexity in trying to conceive of an evolutionary origin for human consciousness. This concession may set the shade of Alfred Wallace to chortling, but it will draw readers into an honest confrontation with a profound enigma. Bryce Christensen. (shrink)

First of all, we would like to gratefully thank all commentators for the attention and effort they have put into reading and responding to our review paper [this issue] and for useful observations that suggest novel applications for our framework. We understand and accept that some of our claims might appear controversial and raise skepticism, because the overall neural framework we have proposed is difficult to frame in established categories, given its strong multidisciplinary character. To make an example, Elsevier is (...) publishing the British Neuroscience Association (BNA) 2017 Special Issue Collection. However, our paper could not fully fit in any of their Special Issues—attention, motivation, behavior; sensory and motor systems; novel treatments and translational neuroscience; genetics and epigenetics; learning and memory; neurodegenerative disorders and ageing; developmental neuroscience; neuronal, glial and cellular mechanisms; neuroendocrine and autonomic nervous systems; psychiatry and mental health; methods and techniques. Perhaps because our paper was mathematically, physically, biologically (neuroscientifically), and phenomenologically motivated from the start? Nevertheless, venturing in novel, fresh, testable proposals is badly needed in contemporary neuroscience, so to break into “the utter darkness of the inner mechanism of psychic acts… during the production of the concomitant phenomena of perception and thought, namely, feelings, consciousness and volition”—as Cajal had already observed in his opus magnus ‘Textura’. But as he soberly confessed: “This ideal is still very distant” (Ramon y Cajal, 1899-1904, p. 1,141). In the pursuit of that very ideal, neuroscience and psychology have had, and continue to have, a plethora of movements and schools of thought: behaviorism, cognitivism, neural Darwinism, social constructivism, Bayesian optimization...In our paper, we propose to go a step further, via the notion of topodynamics, towards “projectionism.” In what follows, trying to elucidate the main features of this Emperor’s new clothing, we proceed with the responses to the comments received. (shrink)