Descartes and the pineal gland in animals: a frequent misinterpretation

An entire universe of the Roman world's architecture found in the human skull

Today's neuroanatomical terminology has its origins in the Romans' way of life, in their civil and military house architecture, as well as in the fields of engineering and technology. Despite the fact that they did not know how the nervous system worked and what the role of each neuroanatomic structure was, over time, especially in Renaissance and early modern times, the anatomists sought descriptive names for the nervous structures they have identified by way of similarity with some ancient items. This study aims to briefly review the influence of Roman architecture, engineering, and technology on neuroanatomic nomenclature, the precursor of modern neuroanatomical terminology.

Descartes and His Peculiar Sleep Pattern

Rene Descartes (1596-1650) was a mathematician, philosopher, and scholar, whose work set a foundation for modern science. Among other interests, he focused on locating the "core and the seat of the soul" and concluded that the pineal gland was such a structure. Recent scientific findings validate Descartes' deep interest in pineal gland, appreciating its role as part of the circadian rhythm system. On the other hand, the biographical information suggests that Descartes had an aberration of the circadian rhythm (delayed sleep phase). Coincidentally, this meant that one of the most important things in his private life and one of the most significant areas of his research intersected in an overlooked way.

Sadness as a passion of the soul: a psychopathological consideration of the Cartesian concept of melancholy

The relationship between the "passions" (emotions or feelings) and psychopathology has been a constant throughout the history of medicine. In this context, melancholy was considered a perversion of the soul (corruption of the passions). One of the most influential authors on this subject was René Descartes, who discussed it in his work The Treatise on the Passions of the Soul (1649). Descartes believed that "passions" were sensitive movements that the soul experienced due to its union with the body (res extensa). According to this theory, the soul was located in the pineal gland, where it was actively involved in overseeing the functions of the "human machine" and kept its dysfunctions under control, by circulating animal spirits. Descartes described sadness as one of "the six primitive passions of the soul", which leads to melancholy if not remedied. Cartesian theories had a great deal of influence on the way that mental pathologies were considered throughout the entire 17th century (Spinoza, Willis, Pitcairn) and during much of the 18th century (Le Cat, Tissot). From the 19th century onwards, emotional symptomatology finally began to be used in diagnostic criteria for mood disorders.

Chapter 12: the anatomical foundations of clinical neurology

The chapter provides an itinerary of knowledge on nervous system anatomy as one of the pillars of clinical neurology. The journey starts from the Renaissance explosion on the approach to the human body, its functions and its diseases, dealing with the seminal contributions of Leonardo da Vinci and Vesalius. The itinerary proceeds through the contributions of the 17th century, especially by Thomas Willis and the pioneering investigations of Marcello Malpighi and Antony van Leeuwenhoek, and onto the 18th century. The itinerary thus leads to the progress from gross anatomy to the microscopic investigation of the nervous system in the 19th century: the reticular theories, the revolution of the neural doctrine and their protagonists (Camillo Golgi and Santiago Ramón y Cajal), which initiated the modern era of the neurosciences. The chapter also includes sections on the contributions of developmental neuroanatomy to neurology, on the history of tract tracing, and on the cytoarchitecture of the cerebral cortex. The never-ending story of the anatomical foundations of clinical neurology continues to evolve at the dawn of the 21st century, including knowledge that guides deep brain stimulation, and novel approaches to the anatomy of the living brain based on rapidly developing neuroimaging technology.

Five early accounts of phantom limb in context: Paré, Descartes, Lemos, Bell, and Mitchell

PHANTOM LIMB WAS described long before American physician and surgeon Silas Weir Mitchell coined the term and drew attention to the disorder in the 1860s. The early descriptions of Ambroise Paré, René Descartes, Aaron Lemos, Charles Bell, and then Mitchell of this strange consequence of amputation are presented in historical and cultural context. These five men described phantom limbs for various reasons. They also differed when it came to explaining and dealing with these illusory sensations. The rich history of phantom limbs can begin to be appreciated by viewing the contributions of these individuals in perspective and by realizing that their writings represent only a fraction of what was published about phantom limbs more than 130 years ago.

Artful imaging of the brain. From logo to metaphor, about Michelangelo and Kiefer

Michelangelo has painted the fresco 'Creation of Adam' for the Sistine Chapel. Recently it was discovered that he had an outline of the brain concealed in Gods cloud. As a renaissance artist he was not supposed to believe that the brain is the seat of the soul. Only when the concept of structure and function of the central nervous system had developed, artistic presentation of the brain did become possible. The conceptual painter Kiefer, who is possessed by Germany's recent and past history, expressed his apprehension using the philosopher Heidegger and his writings as symbol and a naked brain as metaphor.

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.