Cronología de la investigación sobre la dinámica cerebral de Justo Gonzalo / Chronology of Justo Gonzalo’s research on brain dynamics

Introducción: El neurocientífico español Justo Gonzalo y Rodríguez-Leal (1910-1986) investiga la organización funcional de la corteza cerebral durante más de cuatro décadas. Sus hallazgos le llevan a formular una teoría neurofisiológica basada en las leyes de la excitabilidad nerviosa, que denomina dinámica cerebral. En el presente trabajo se expone de forma cronológica cómo surgen las principales ideas sobre las que se articula.Desarrollo: En 1939 Gonzalo observa los denominados fenómenos de acción dinámica: desfasamiento, facilitación y repercusión cerebral. Le siguen dos principios: efecto cerebral de la lesión según la magnitud y posición (1941), y organización sensorial, según un desarrollo espiral (1947). Paralelamente, caracteriza lo que llama el síndrome central de la corteza cerebral. En la década de los cincuenta desarrolla los conceptos de gradiente cortical, similitud y alometría. En contraposición a las concepciones modulares de la corteza cerebral, en las que una región es responsable de una función, Gonzalo expresa que ‘los gradientes corticales dan la localización de los sistemas mientras la similitud y alometría revelan su trama funcional’.Conclusiones: La teoría de dinámica cerebral se articula en dos etapas. La primera (de 1938 a 1950) se caracteriza por una importante base clínica con observación de nuevos fenómenos y formulación de nuevos conceptos. La segunda (de 1950 a 1960) incluye la introducción de conceptos de mayor alcance, como el gradiente funcional cortical, y leyes de alometría que se basan en un cambio de escala. Actualmente, varios autores consideran que el concepto de gradiente es clave para entender la organización cerebral.(AU)

Introduction: The Spanish neuroscientist Justo Gonzalo y Rodríguez-Leal (1910-1986) investigated the functional organisation of the cerebral cortex over more than four decades. His findings led him to formulate a neurophysiological theory based on the laws of nervous excitability, which he called brain dynamics. This paper presents in chronological order how the main ideas on which it is based arose.Development: In 1939, Gonzalo observed the phenomena of dynamic action: asynchrony or disaggregation, facilitation and cerebral repercussion. This was followed by two principles: the cerebral effect of lesions according to their magnitude and position (1941), and spiral development of the sensory field (1947). At the same time, he characterised what he called the central syndrome of the cerebral cortex. In the 1950s he developed the concepts of the cortical gradient, similarity and allometry. In contrast to modular conceptions of the cerebral cortex, in which one region is responsible for one function, Gonzalo argued that ‘cortical gradients provide the location of systems, while similarity and allometry reveal their functional mechanism.’Conclusions: The theory of brain dynamics was established in two stages. The first (between 1938 and 1950) had an important clinical foundation, involving the observation of new phenomena and the formulation of new concepts. The second (between 1950 and 1960) included the introduction of more far-reaching concepts, such as the functional cortical gradient, and allometry laws based on a change of scale. Today, various authors believe that the concept of the gradient is crucial for understanding how the brain is organised.(AU)

François Rabelais and his dystonic giants.

Spasmodic torticollis was an early designation used for cervical dystonia. The origin of this name is attributed to French physician and writer François Rabelais in the mid-sixteenth century. This early description of torticollis in the book Pantagruel was an inspiration for the understanding of cervical dystonia. The art expressed in Rabelais' literature ‒ which was immortalized by the drawings of Gustave Doré ‒ influenced poetry, art, and photography, and led to the adoption of the term torticollis in the neurological sciences.

Uma designação inicial usada para distonia cervical era torcicolo espasmódico. A origem desse termo é atribuída ao médico e escritor francês François Rabelais em meados do século XVI. Essa descrição inicial do torcicolo no livro Pantagruel foi uma inspiração para a compreensão da distonia cervical. A arte exibida na literatura de Rabelais ‒ imortalizada pelos desenhos de Gustave Doré ‒ influenciou a poesia, a arte e a fotografia, e levou à adoção do termo torcicolo nas ciências neurológicas.

Giuseppe Levi, Natalia Ginzburg, and Lessico Famigliare (Family Lexicon): a seminal figure in the history of neuron cell biology and histology seen through his daughter's literary eyes.

One of the most important figures in the history of neurohistology, Giuseppe Levi (1872-1965) contributed in numerous ways to neuroscience, particularly in the fields of neuronal plasticity and the understanding of sensory ganglia. His daughter Natalia Ginzburg, née Levi (1916-1991), on the other hand, achieved fame as one of the most celebrated Italian writers of the twentieth century. Lessico Famigliare (Family Lexicon), from 1963, is a semibiographical account of her life in which she describes the life and character of her father in detail, providing depth and complexity to a seminal figures in the development of neuroscience. A thorough reading of the book enables modern neurologists to fully appreciate Levi's life and contributions, by means of humanizing him and giving context to his life and works. The present article provides a summary of Levi's and Natalia's lives and times as well as an analysis of the book and of the intimate, vivid descriptions of the neurohistologist's life.

Uma das figuras mais importantes da história da neuro-histologia, Giuseppe Levi (1872­1965) contribuiu de diversas maneiras para a neurociência, particularmente no campo da plasticidade neuronal e na compreensão dos gânglios sensitivos. Sua filha Natalia Ginzburg, nascida Levi (1916­1991), pelo contrário, adquiriu fama como uma das escritoras italianas mais célebres do século XX. Lessico Famigliare (Léxico familiar), de 1963, é um relato semibiográfico de sua vida, na qual ela descreve a vida e o comportamento de seu pai em detalhes, e confere profundidade e complexidade a uma figura seminal no desenvolvimento da neurociência. Uma leitura aprofundada do livro permite que neurologistas modernos apreciem a vida e as contribuições de Levi de forma mais completa, o humanizando e dando contexto a sua vida e suas obras. O autor resume as vidas e épocas de Levi e Natalia, bem como avalia o livro e as descrições íntimas, vívidas, da vida do neurohistologista.

Carl Wernicke of the Wernicke Area: A Historical Review.

The Wernicke area, also known as Brodmann area 22, is located in the posterior segment of the superior temporal gyrus in the dominant hemisphere. Carl Wernicke, a German neurologist, described this area in 1874. The life story of Carl Wernicke, a 19th-century medical genius, remains an inspiration for all neuroscientists even a hundred years later. We outline Wernicke's life story and academic achievements in neurosurgery, neurology, and psychiatry. We explore his remarkable ability to turn his many setbacks into steps forward, his controversial foray into psychiatry, and his wide-ranging set of contributions, including his work on external ventricular drainage for hydrocephalus and encephalopathy; his description of the eponymous Wernicke area; and his field-defining work on aphasia. This historical review attempts to bring to life a seminal figure in the neurosciences, providing an insight into his visionary thought process.

[Henry Head (1861-1940) and his importance for neurology]. / Henry Head (1861­1940) und seine Bedeutung für die Neurologie.

Nowadays, Henry Head is best known for his Head zones. The concept was understood very differently by Head in comparison to what current medical books falsely describe them to be. In reality, there is no direct relationship between one particular skin zone and one single organ. It is certain that the drawings considered depictions of the Head zones in today's medical textbooks were actually not created by Head. From a neurological point of view, Head is important for two reasons: his self-experiment in 1909 to damage one of his own peripheral nerves followed by regeneration was heroic. It has helped generations of neurologists to have a better understanding of the pathophysiology of peripheral nerve damage and thus make a better assessment of the prognosis of such injuries. Head's second contribution pertains to the radicular organization at the level of the spinal cord. The pathophysiology of herpes zoster radiculitis enabled him to develop the concept of the dermatomes on the basis of preliminary work around 1900. Henry Head's contribution was the systematic compilation of the existing publications of the time and amendment of his own cases. As he was the most important neurologist at that time, at least in the English speaking world, and was well connected with people in the German neurology community, it was probably easy for him to make his dermatome maps well known. In retrospect, Head was less successful in neuropsychology with holistic concepts for higher cognitive functions which were in vogue during his lifetime. His late work on aphasia is now considered refuted. Head's criticism of the strict localization was well in syncronization with the zeitgeist of the early twentieth century. Establishing the fact that Broca's aphasia and Wernicke's aphasia are not easily diagnostically distinguishable from each other was more an achievement of subsequent generations of neurologists and neuropsychologists as well as technical advances.

Herbert Coddington Major (1850-1921).

Herbert Coddington Major (Fig. 1) was a late nineteenth century pioneer in neuropathology and comparative neurology. No previous biographical article has been identified, suggesting he is now almost totally, yet unjustifiably, forgotten.

André-Thomas (1867-1963), Initiator of Neonatal Neurology.

After a brilliant career as a clinician and anatomopathologist, André-Thomas (1868-1963) spent the last 30 years of his life validating the components of neurological examinations of newborns and infants. This novel approach was developed through long examinations of several hundreds of normal and sick children, notably those with anencephaly. By combining his vast knowledge of physiology with the results of his experimental work, André-Thomas built the foundations of a speciality that did not exist before his time: neuropaediatrics. His Études neurologiques (neurological studies), medical in nature but also very literary, echoing his illustrious predecessors of the 19th century, made him a transmitter of knowledge, a man of transition, from the anatomoclinical method of the 19th century to the standardised investigation techniques of the 20th century.

From hysteria to gait dementia: History of the concept of astasia-abasia.

Paul Blocq (1860-1896) and his teacher Jean-Martin Charcot (1825-1893) introduced the expression "astasia-abasia" into medical terminology in 1888 to designate a pathology they believed to be caused by hysteria. This condition makes it impossible to remain erect and to walk, whereas the ability to move the legs while lying down remains normal. At the turn of the 20th century, and now almost exclusively, this motor disturbance is recognised as a syndrome with multiple possible organic causes, and now described as "higher-level gait disorder". After briefly mentioning earlier descriptions by other authors, I will review Charcot's Tuesday lessons in 1889 that covered astasia-abasia and elucidated the beginnings of the breakdown into organic aetiologies: medial-frontal and corpus callosum tumors, damage to the cerebellar vermis, lacunar state as described by Pierre Marie (1853-1940), Parkinson's disease, and Parkinson-plus syndrome. The long history of astasia-abasia reveals a cluster of neurologists, often emerging from oblivion herein and all of whom, through the precision of their clinical examinations and their pathophysiological findings, helped advance the understanding of the mechanisms by which human beings are the only erect, constantly bipedal mammals, whether immobile or walking.

Future of Neurology & Technology: Neuroimaging Made Accessible Using Low-Field, Portable MRI.

In the 20th century, the advent of neuroimaging dramatically altered the field of neurologic care. However, despite iterative advances since the invention of CT and MRI, little progress has been made to bring MR neuroimaging to the point of care. Recently, the emergence of a low-field (<1 T) portable MRI (pMRI) is setting the stage to revolutionize the landscape of accessible neuroimaging. Users can transport the pMRI into a variety of locations, using a standard 110-220 V wall outlet. In this article, we discuss current applications for pMRI, including in the acute and critical care settings, the barriers to broad implementation, and future opportunities.