The Journey of Discovering Skull Base Anatomy in Ancient Egypt and the Special Influence of Alexandria

Ali M. Elhadi, M.D.; Samuel Kalb, M.D.; Luis Perez-Orribo, M.D.; Andrew S. Little, M.D.; Robert F. Spetzler, M.D.; Mark C. Preul, M.D.


Neurosurg Focus. 2012;33(2):e2 

In This Article

Erasistratus of Chios: 304–250 BC

Erasistratus was a well-known physician born on the island of Chios. He worked with Herophilus, and some believe that he continued Herophilus' work after his death.[16] Together, they contributed considerably to medical investigations and teaching in Alexandria.[5] While Herophilus was very talented in describing human anatomy, Erasistratus contributed to physiology and functional anatomy. Erasistratus received his medical education in Athens. It is believed that he came from a family of doctors, although Pliny records that he was a grandson of Aristotle through his daughter Pythias.

Erasistratus became famous when he cured the disease of Antiochus, the son of King Seleucus, Nicator I of Syria, to whom he had served as a courtier. Erasistratus is famed for his interaction with the aged King Seleucus, who married a young woman (Stratonice). She was so beautiful that Antiochus fell ardently in love with her. Because Stratonice was his mother-in-law, however, Antiochus hid his passion and pined away in silence. Physicians were unable to determine the cause of Antiochus' disease. Even Erasistratus himself found nothing wrong with Antiochus' body until he noticed that whenever Stratonice entered the room, Antiochus' skin would become hotter, his color would heighten, and his pulse would increase (Fig. 8).

Figure 8.

Painting by Jacques-Louis David illustrating the tale of Erasistratus discovering the love of Antiochus for Stratonice. This painting won David the Académie des Beaux-Arts' first prize in 1774. On the left Erasistratus is seated while Antiochus lies in bed. On the right Stratonice is standing and Seleucus leans forward. Image available at

Erasistratus began to think that Antiochus' disease was in his mind and suspected that he might be in love. Erasistratus told the king that his son's malady was incurable because he was in love and that it was impossible for his passion to be gratified. The king asked Erasistratus with whom his son was in love, to which Erasistratus (untruthfully) replied, "My wife." Erasistratus then inquired whether the king would be willing to give up his own wife if the object of his son's affection was Stratonice. The King was willing to do so to cure his son. Erasistratus then told the king that his son was indeed in love with Stratonice. The king not only gave up Stratonice, but he gave his son several provinces of his empire to rule. Erasistratus received 100 talents for restoring the prince's health, which could be a record for the largest sum ever received for a medical fee.[29]

Erasistratus moved to Alexandria and worked with his contemporary Herophilus in medical teaching and anatomy. Erasistratus wrote extensively on anatomy, practical medicine, and pharmacy, although we know only the titles of his works. Galen, Caelius Aurelianus, and others record many of the shorter fragments of Erasistratus' writings. In fact, Erasistratus may be called the father of ancient anatomy because of the celebrated systematic observations that he recorded. For example, he appears to have been very close to discovering the circulation of the blood: "The vein arises from the part where the arteries, that are distributed to the whole body, have their origin, and penetrates to the sanguineous [or right] ventricle [of the heart]; and the artery [or pulmonary vein] arises from the part where the veins have their origin, and penetrates to the pneumatic [or left] ventricle of the heart."[39]

Erasistratus' observations were only surpassed much later in the 17th century by William Harvey. Erasistratus was a talented observer. He noticed that all veins and arteries arise from the heart but believed that they carried air. He described the ventricular system of the brain much as it is known today: "I investigated the nature of the brain… . And it had a ventricle placed longitudinally on each side, and these were pierced through into another one at the junction of the two parts. This one extended to the so-called cerebellum, where there was another, smaller ventricle, each side walled off by membranes; for the cerebellum was set off by itself."[14]

Erasistratus differentiated between motor and sensory nerves, although he thought that they were hollow and carried a kind of animal spirit. When carried to the muscle (through motor nerves), this animal spirit caused the muscle to balloon and shorten. So Erasistratus explained muscle contraction. He thought that the sensory nerves arose from the membranes covering the brain and that the motor nerves arose from the brain matter itself. Rufus of Ephesus wrote, "According to Erasistratus there are two kinds of nerves, sensory and motor nerves; the beginning of the sensory nerves which are hollow, you could find in the meninges of the brain, and those of the motor nerves in the cerebrum [enkephalos] and in the cerebellum [parenkephalis]. According to Herophilus on the other hand, the neura that make voluntary motion possible have their origin in the cerebrum [enkephalos] and spinal marrow, and some grow from bone to bone, others from muscle to muscle, and some also bind joints together."[20]

Erasistratus followed certain nerves from their origin to their target organs: "All the processes of the nerves were from the cerebrum; and, in brief, the brain appeared to be the origin of the nerves of the body; for the sensation which comes from the nostrils reaches this opening [olfactory plate?], likewise coming from the ears. Processes were also carried from the brain to the tongue and eyes."[14] With these words, Erasistratus corrects his previous thoughts about the sensory nerves originating from the meninges. Rather, he states that all nerves originate from the brain matter.

From his studies we can be certain that Erasistratus was a careful observer and dissector of the skull base and base of the brain. At the time, this was a remarkable accomplishment given that the brain tissue or crania were probably not preserved in any manner. These investigations must have resulted from vivisections or dissections performed soon after the death of his subjects. One can only imagine the team of Herophilus and Erasistratus in what must have been a filthy, bloody, fly-ridden scene probably performing demonstrations in an outdoor portico or courtyard for light. We would regard such demonstrations as nothing short of horrid. However, for the ancient Alexandrians, death, perhaps even gruesome death, was a familiar part of everyday life. Such events would have been regarded as the most progressive education of the period to which students flocked from all over the Mediterranean world.

Erasistratus provided a clear distinction between the cerebrum and cerebellum and viewed the brain as the source of intelligence. He compared the human brain with the brains of other animals and concluded that the greater the number of convolutions, the greater the intelligence: "the Cerebrum was constructed from even more and differing foldings. From this the observer may learn that as in those animals that surpass the others in speed of running such as the stag and hare, well constructed with muscles and nerves also for this, so also, since the man greatly surpasses other beings in intelligence, his brain was greatly convoluted."[14] Interestingly, Erasistratus was interested in knowing the blood supply of the nerves, introducing the idea that the nerves had small veins that supplied them with nourishment and that these veins varied according to the size and territory of the nerve. If a nerve had a rich supply around it, it did not need an independent supply.

Together, Herophilus of Chalcedon and Erasistratus of Chios defined considerable skull base anatomy, which opened the door to future discoveries. Because they were contemporaries, one cannot be mentioned without the other. Despite the reputation and outstanding medical education offered by the medical school in Alexandria, most of their work and that of the ancient Egyptians were stored in the Royal Library of Alexandria. In 48 BC, however, Julius Caesar burned this library,[13] perhaps accidentally, during his war on Alexandria. The fire that Caesar had set to destroy the Egyptian fleet extended from the dockyards to the library, which at that time housed almost 500,000 scientific and historical scrolls among others. This loss may account for the subsequent fragmentation of medical knowledge and explain why most of the information that is now known dates from later historians. After Herophilus and Erasistratus, no one contributed as much to the field of neuroanatomy for nearly 3 centuries until Rufus of Ephesus came to Alexandria.[12]


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: