The two Drs. Edinger who deserve greater recognition
Every student of neuroanatomy learns about the accessory oculomotor nucleus which subserves the function of conveying parasympathetic impulses to the ciliary muscle and the sphincter of the iris. This nucleus has been linked to two names – Ludwig Edinger of Frankfurt and Karl Friedrich Otto Westphal of Berlin. Edinger demonstrated the presence of the nucleus in the fetus in 1885 and Westphal confirmed its presence in the adult in 1887. Here we shall concern ourselves principally with the life and work of Dr. Edinger.
Interesting as his life and work are, their account is rivalled by the story of the life and work of his daughter. Both were pioneers in their fields and deserve acclaim.
Dr. Edinger was born in Worms, a city in Rhineland-Palatinate. It is situated on the upper Rhine, northwest of Mannheim and 60 km. south-west of Frankfurt on the Main, Germany. His father was a textile merchant and his mother, the daughter of a physician. When he was aged 14 years, his mother gifted him a microscope. 'I shall never forget my ecstasy', he wrote later. He learnt the technique of embedding and mounting his own specimens.
He studied medicine from 1872-1877 in Heidelberg and Strasbourg.
Lewey (1970) informs us that in Strasbourg, Edinger worked in the tower above the hospital and found the work of Wilhelm Waldeyer (1834-1921) stimulating. Waldeyer supervised his publication 'On the histology of the mucosa of fish and some remarks on the phylogenesis of the glands of the small intestine.'
Edinger was taught pathology by Dr. Freidrich Daniel von Recklinghausen (1833-1910). Recklinghausen's paper describing neurofibromatosis was published in 1882, after Dr. Edinger had moved on. Dr. Edinger served as an assistant to Dr. Adolf Kussmaul (1822-1877). You will recall that Kussmaul also described dyslexia (which he termed word blindness), progressive bulbar paralysis and selective mutism (then termed Kussmaul's aphasia), in addition to the better known abnormal breathing seen in severe diabetic ketoacidosis and the paradoxical rise in jugular venous pressure in constrictive pericarditis and chronic obstructive pulmonary disease.
In 1877, Dr. Edinger was appointed as assistant physician to Dr. Franz Riegel (1843-1904) in the University of Giessen, located to the north of Frankfurt. Wilhelm Konrad Roentgen, also from this city, was almost unknown then. (Neurosurgeons of my vintage will recall that Professors H. W. Pia and Ernst Grote from this University had visited India and conducted workshops in Delhi, Calcutta and Bombay that introduced microneurosurgery to our country.) Edinger received his Habilitation – the German equivalent of a doctorate – in 1881, whilst he was aged 26 years. (The word is derived from the Latin term habilis, signifying fitness and the acquisition of the skills necessary for senior academic positions).
He embarked on an academic pilgrimage and visited Sir William Gowers (1845-1915) in London. He also attended the clinics of Dr. Jean-Martin Charcot (1825-1893) in Paris, Drs. Karl Westphal (1833-1890) in Berlin, Paul Flechsig (1847-1929) and Wilhelm Erb (1840-1921) in Leipzig.
On his return to Giessen, he was barred from an appointment as Privatdozent which would have allowed him to teach and examine candidates on the grounds that he was of the Jewish faith.
He was forced to move to Frankfurt in 1883, where he established himself as a neurologist – the first to do so in that city. Frankfurt was a free town of the old German Empire, famed for its liberal tradition.
Dr. Carl Weigert (1845-1904), Director of the Department of Anatomy in Frankfurt gave Dr. Edinger a place to work. Drs. Edinger and Weigert soon embarked on mutually rewarding studies. Dr. Edinger worked at the Senckenberg Foundation. Initial researches were carried out in his bedroom, which also served as a laboratory. A gynaecologist, his erstwhile colleague in Giessen, sent him a regular supply of human foetuses. These were the first subjects of his study. 'As he did not dare to antagonize his landlady, these small parcels were treated with great secrecy and the remainder of the bodies burnt when she went out shopping.'
After a dispute, Dr. Edinger left the foundation to join the Goethe University of Frankfurt, where he set up a neurology institute. Dr. Edinger was appointed full Professor in 1914. Drs. Gordon Holmes (1876-1963), Korninian Brodmann (1868-1918), Kurt Goldstein (1878-1865), and the American embryologist, George Linius Streeter (1983-1948) were among his students who worked in this institute.
He founded the branch of comparative neuroanatomy.
His work soon enabled him to publish path breaking papers. He differentiated the ventral and dorsal spino-cerebellar tracts. Together with Dr. Adolf Wallenberg (1862-1949), Dr. Edinger distinguished between the paleo-encephalon from the neo-encephalon and the paleo-cerebellum from the neo-cerebellum, identified the nucleus of the oculomotor nerve, named after him and Westphal, and defined the terms gnosis and praxis. He was the first to describe thalamic pain, having done so 15 years before the description by Gustave Roussy (1874-1948) and Joseph Jules Dejerine (1849-1917) was published.
He delivered a course of lectures on his studies of the brain during the winter of 1883-1884. They were later published in German and translated into many languages. His preface to the first edition ended with this paragraph:
'The author, in common with all those who have actually worked in this difficult field, well knows that very few facts are indisputably settled, and that no region of anatomy is more subject to change than the one under consideration. He, therefore, himself calls attention to the fact that possibly here and there, a line or point may be laid down a little too confidently. This, however, has nowhere been done in the interests of didactic clearness alone.'
The second edition contained several changes as 'Much that is new has been discovered during the last four years. The author has endeavoured to embody the most important of these discoveries in this book. The chapters on histology and histogenesis have been entirely rewritten.'
The table of contents reproduced in [Figure 1] shows how he added methods for investigating the nervous system, embryology and comparative neurology to discussions on the structure and function of various components of the brain, spinal cord and peripheral nerves.
Dr. Edinger used the Weigert stain during his studies of the human brain and the brains of lower vertebrates. He provided comparative accounts, as of the development of fibre systems such as the spino-thalamic tract. He collaborated with Dr. Adolf Wallenberg on a detailed study of the brain in birds and showed that the primitive forebrain mantle is largely controlled by olfactory impulses. (Dr. Wallenberg described the clinical lateral medullary syndrome named after him in 1895 and showed the autopsy findings responsible for it in 1901).
Dr. Edinger also influenced the work of Dr. C. U. Ariëns Kappers (1877-1946), the first Director of the Netherlands Central Institute for Brain Research. Glees (1952) recalled, 'When I was working with Kappers, Edinger was frequently quoted and throughout his whole life, Kappers showed great affection and admiration for Edinger.'
Dr. Edinger's driving ambition appeared to be the development of a theory on the evolution of the brain and cognition in man. Evolution of our brains, he argued, resulted from addition of different components step by step. The progression could be identified by a study of the brains in fish, amphibians, reptiles and birds. The cerebral cortex was added and developed in complexity in mammals. In his papers, he discussed the presence in the human brain of the reptilian, paleomammalian and neomammalian components.
Dr. Edinger was also an artist and delighted his students by drawing the structure of a segment of the brain with his left hand, as he wrote the legends to the areas shown with his right hand.
His guiding principle during his studies had always been 'to investigate brain anatomy alone (and not function) is to pursue a sterile science'.
Dr. Edinger was known to have arteriosclerosis of his coronary arteries. He underwent an operation after which he had a myocardial infarction that caused his death in 1918 at the age of 63 years. He had requested an examination of his brain post-mortem.
Drs. Walther Riese and Kurt Goldstein describe the findings of their study of Dr. Edinger's brain in a detailed paper illustrated with photographs of the brain (1950). 'Ludwig Edinger seemed to have outstanding gifts in the optic and motor spheres…(he) was pronouncedly left-handed…Ludwig Edinger was decidedly an original thinker… It was this wealth of ideas which made him so unusually attractive to his students and which continually caused him to attack new problems…
'…the increase in the surface within the right frontal, parietal and occipital lobe (have been) described in detail. Ludwig Edinger's brain is characterized by a remarkable asymmetry as regards both convolutions and fissures. In the left hemisphere, the fissures take a straighter course, their pattern is simpler and more schematic, while the right hemisphere exhibits a more complicated fissural pattern…' The right frontal, parietal and occipital lobes showed a larger mass than that on the left. 'The increase of surface within the right occipital lobe makes itself most clearly felt in two places: the right occipital lobe has a so-called operculum explicable by an increase in substance… the right cuneus is by far larger than the left one… the whole right parietal lobe is much larger and richer in convolutions…'
They concluded: 'In view of the former morphological investigations of the brain (sic) of prominent people one is justified to correlate the cerebral asymmetry with Edinger's general mental gifts and can argue that a wide deviation from the average…creates favorable conditions for the development of asymmetries…. Frontal, parietal and occipital lobes appear to be preferred… (these asymmetries were) an instrumental… condition of Edinger's highly pronounced visual gifts and … for his manual skill.'
Modern paleoneurology was founded almost single-handed by Ottilie ('Tillie') Edinger in the 1920s. She was one of the first to systematically investigate, compare, and summarize fossil brain data from the various collections in Europe and North America. She realized that insights into brain evolution could be extended considerably by focusing on animal groups whose lineages were already well-established from independent stratigraphic work, by taking artificial brain casts from existing museum specimens, and by utilizing established methods of comparative anatomy.'
The account of her life and work is at once inspiring and saddening.
Her childhood in the home of her parents - Dr. Ludwig Edinger and his wife, Anna Goldschmidt – was filled with comfort and intellectual stimulation. She was taught by a governess and a private tutor till she started school in Frankfurt. She was introduced to several languages at a young age, met some of the leading intellectuals of the day as a child and was encouraged to follow her own inclinations. She studied natural sciences in Heidelberg, Munich and Frankfurt. Her doctoral degree in 1919, from the University of Frankfurt, was based on her chosen subject – paleontology. Her interest in this subject had been sparked off by Othenio Abel's Principles of Vertebrate Paleobiology [Othenio Lothar Franz Anton Louis Abel (1875-1946) was an Austrian who founded the science of paleobiology – the study of life and environment of fossilized organisms].
Her first publication in 1921 was on the endocranial cast of Nothosaurus. As a control, she studied the cast of an alligator. (The Greek word nothos is translated as illegitimate and sauros as lizard. Nothosaurus is an extinct reptile from the Triassic period, approximately 240-210 million years ago).
'By the end of the decade she had established the field of paleoneurology and became its leading practitioner and chronicler.'
Dr. O. C. Marsh (1831-1899) was the leading paleontologist of the 19th century and Dr. Tilly was initially guided by his writings but she soon found grounds for disagreement based on her documented findings. In 1929, she published a review of 250 pages entitled Die fossilen Gehirne (The fossil brains) and dedicated it to the memory of her father. This book described historical work on the subject, contemporary information and outstanding questions that remained unanswered. She developed an interest in paleo-endocrinology (a term she coined). She attempted to predict the relative size of the parietal eye (parapineal organ) and postulated that the midline location of the pineal gland was a more recent development in evolution.
In the 1930s, worsening anti-Semitism in Germany took its toll. She was informed in 1937 that she was no longer a reviewer for the journal Neues Jahrbuch für Mineralogie, Geologie, und Paläontologie. The next year, she was taken off the panel of reviewers for Zentralblatt and Fortschritte. Buccholtz and Seyfarth (1999) refer to her struggle to retain her position on the staff of the Senckenberg Foundation. When urged to leave Germany in view of the impending holocaust, she wrote, 'So long as they leave me alone I will stay. After all, Frankfurt is my home, my mother's family has been here since 1560, I was born in this house. And I promise you they will never get me into a concentration camp. I always carry with me a fatal dose of veronal.'
Her brother, Fritz, died in a concentration camp. The Nazis removed the street sign Edingerstrasse, named after her father and destroyed a bust of her mother, Anna, in a city park. Threatening forces now made it necessary for her to apply in August 1938 to the American consulate for entry into the United States.
Despite testimonials from eminent scientists, entry into America was delayed by the Consulate. Eventually, the Society for the Preservation of Science and Learning in London arranged a visa for her to travel to London on the express condition that she would leave England for a position in America by 1940. Leaving being most of her possessions in Germany, she left Germany for London in May 1939. She survived in London by serving as a translator of medical texts from German to English. She travelled to the United States on 11th May 1940.
This was a sad state for one who had been dispossessed for no fault of her own.
On arrival in America, she was appointed Research Associate in Paleontology by Harvard University. The spadework for this appointment had been done by Dr. Alice Hamilton (1869-1970) [Dr. Hamilton was the first woman to be appointed to the faculty of Harvard University in 1919. The headline in New York Tribune, 'A woman on Harvard faculty – the last citadel has fallen' was elicited from her the observation, 'Yes, I am the first woman on the Harvard faculty – but not the first one who should have been appointed.' She was made Professor Emeritus at Harvard in 1935].
Dr. Hamilton's assistance to Dr. Edinger may, in part, have been prompted by the fact that she had stayed with Tilly's parents during her visit to Germany in 1896.
Dr. Edinger's work at Harvard for over twenty years helped in the creation of the book, Bibliography of Fossil Vertebrates Exclusive of North America. She supplemented her meager stipend with income from translations, abstracting German papers for the Geological Society of America and by teaching comparative vertebrate anatomy at Wellesley College. She published papers in journals such as The American Journal of Science and Quarterly Review of Biology. Her initial work was on the evolution of cerebral sulci and increase in the size of the brain in horses, the earliest specimen studied being that from the Eocene period (56-40 million years ago). The resulting monograph was followed by the award of an honorary doctorate at Wellesley College.
One of her papers that may interest our readers is on the pituitary body in giant animals. The work on which the findings described in this paper was based had necessitated the study of fossils in the British Museum and in the museum of the Royal College of Surgeons. She noted that the endocranial casts at the Royal College were stored in a bomb proof cellar. The collections in the museum of this college dated back to 1540. The college commenced their storage of specimens out of harm's way in fortified rooms, basements and sub-basements from 1938. Despite this care, when a German bomb did strike the college at 12.55 a.m. on 11 May 1941, two rooms of the main gallery were destroyed. Parts of the basement were also damaged by fire. Half of the museum's collection of 6,000 specimens were lost.
Dr. Edinger showed that as dinosaurs and other prehistoric animals grew to enormous sizes, their skulls showed a corresponding increase in the volume of their pituitary fossae. She quoted Dr. Grafton Elliott Smith's statement in 1902 that the endocast of the cranial cavity of a giant Moa showed that 'the hypophysis is very large.' [Dr. Smith (1871-1937) was famed for his studies in anatomy and on the brains of Egyptian mummies, using x-ray films for the latter purpose. He was the leading specialist on the evolution of the brain in his time. The moa were flightless birds in New Zealand that became extinct in the 14th or 15th centuries.] She built on that statement and pointed out that comparative anatomists were well aware that the brain and neurocranium in larger animals are disproportionately smaller than would be expected in relation to body size. Her studies on fossils showed that 'Phylogenetic development of gigantism in reptiles, birds and mammals was found to be accompanied by a striking enlargement of the pituitary fossa which can only be due to an enlargement of the glandular lobe which secreted the growth hormone. In giant Jurassic dinosaurs, the volume of the fossa hypophyseos may amount to 10 percent of the brain-case volume.'
She published over a hundred papers and several books. Her work transformed paleoneurology 'into a discipline that was taxonomically, chronologically and functionally informed.'
By 1948, progressive deafness – a consequence of otosclerosis – had become a major handicap. It made discussions at scientific meetings difficult. She also withdrew from large social gatherings but continued to contribute papers for publication and talk to learned societies. She carried on a lively correspondence with others active in her field of interest. She was not inclined to carry out studies involving formulae and logarithmic graphs as she claimed that she did not understand them.
In 1963, she was the first woman to be elected President of the Society of Vertebrate Paleontology. She retired from Harvard University in 1964 but continued to serve as a foreign ambassador for the Society.
On 26 May, 1969, at the age of 69 years, she was knocked down by a vehicle as she was walking along the road. The accident may have followed her inability to hear the approach of the vehicle. She died the next day from her injuries. Her continuing studies were completed by her colleagues and published posthumously in 1975.
Whilst Edinger père [French word that is used after a surname to distinguish a father from a son of the same name] commands respect in his own right, our respect for the many and important contributions made by his daughter is tinged with sadness. Her upbringing had not prepared her for the manner in which the Nazis treated her – as they did others of the Jewish faith. Her death following a physical handicap cut short a career where more could have been expected of her by way of scientific contributions.
I am grateful to Dr. Reeta Mani, Department of Virology, NIMHANS, Bangalore for sending me the full texts of relevant papers that I could not access.