From the beginning of recorded time, sleep has played a central role in human lives, and several theories regarding sleep have been advanced and described throughout the centuries. Sleep was considered both a method of healing and a God: in Ancient Greece, Hypnos (Yπνος) was the personification of sleep, and Somnus represented the counterpart in Roman mythology. Despite the scarce scientific literature on historical issues, a substantial amount of information regarding sleep, sleep disorders, and sleep habits of Greek and Roman ancestors can be obtained by the writings of various Latin and Greek philosophers and poets. Some archaeological findings have also helped experts to understand sleep habits and sleep arrangements. We believe that by exploring and learning from Mediterranean ancestors, we can solidify today’s knowledge of sleep and sleep medicine.

Greece

In Greek mythology, Hypnos was an important and beloved God. According to Homer, Hypnos lived on the island Lemnos (Λήμνος) in a cave next to a river, where day and night met. Pausanias, in his work in the second century A.D., wrote that Hypnos was a dearest friend of the Muses (Μούσες). Hypnos had a twin brother, Thanatos (Θάνατος), “death,” and their father was Hades (Άδης), who was the God of the underworld. In some writings, Hypnos also had a wife, Pasithea (Πασιθέα), the goddess of hallucination and relaxation, and Morpheus (Μορφέας) was his son, who appeared in dreams in human form.

The first studies on sleep were also born in Greece. It was in 460 B.C.E., on the small Aegean island of Cos, where Hippocrates, the most outstanding figure in the history of ancient medicine, was born. Hippocrates identified sleep as one of the six prerequisites to maintain health. In his book “Breaths” (περί φυσών), it is explained that sleep causes a drop of body temperature, slowing blood circulation in the brain. This “cooling” was thought to alter consciousness, which could enable “certain fancies,” the dreams. His famous “Aphorisms” revealed with accuracy the diagnostic significance of sleep in diseases:  “A disease in which sleep causes distress is a deadly one, but if sleep is beneficial, the disease is not deadly.” Hippocrates also argued that “both sleep and sleeplessness, when beyond measure, constitute disease” and recommended to follow certain sleep habits, suggesting that “the patient had to follow the natural custom of being awake during the day and asleep during the night… should this be changed it constituted a bad sign.” He also noticed that “there is no sense perception during sleep, the body cannot perceive external stimuli, neither can sensations reach the body from the outside. It is the soul, the unconscious state, which not only keeps its functions but also even takes over the functions of the body during sleep.”

Hippocrates also had his theories on dreaming. Indeed, he emphasized “the role of dreams as a significant indicator of the dreamer’s physical condition.” Furthermore, he provided a theoretical basis for the use of dreams as a source of information about the condition of the body and gave dreams the most prominent status in his “prodiagnostic” theory. Interestingly, according to Hippocrates, there were two types of dreams: those sent by the gods, and those sent by the soul. For ancient Greeks, dream interpretation often determined the course of a treatment and was used in the following centuries both in established secular practice and at religious healing sanctuaries.

Another peculiarity of ancient Greek culture was that Greeks believed that the psyche (ψυχή=soul) was revealed in sleep, not through the semiotics of dreams but through the peculiar state of being we normally occupy while asleep. As a “borderland between living and not living” (as Aristotle mentioned in one of his writings), sleep offered unique access to the psyche, that element within the self that is unassimilable to waking consciousness.

Sleeping habits in Greece

What is now known about the sleeping habits of the Ancient Greeks is that they had a couch/bed called “kline” (κλίνη) that was used for lounging and sleeping (hence our word “recline”) from which also the word clinic and clinical is derived. It was made of wood or bronze and was often richly adorned. Plato said that, “Only men and courtesans could lounge on the kline.” Women served food and drink to those resting, and they were allowed to sleep on the beds at night. It is known that slaves had their own rooms. From ancient writings, we understand that the Greeks used to go to sleep after evening meal called symposium (συμπόσιο). This was the dinner where people used to eat and drink discussing different topics related to everyday life. They used to wake up early in the morning to go to the Agora or to the local parliament.

Rome

The Romans had the cult of the god of sleep under the name of Somnus, who was often depicted as a naked youth with wings on his head holding poppies in his hand, a flower he shared with his brother Mors and his mother Nox. Typically, Greek and Roman mythologies shared the same characters and stories even though characters are named differently, and they might behave differently. For example, contrary to what we found in Greek writings, Somnus (as described by Ovid in the “Metamorphoses”) was a God who lived in a cave, never reached by light, in the country of the Cimmerians. Roman Somnus was probably more similar to the Greek Morpheus than to the God Hypnos. He was indeed described to be a deceiver, with changeable disguises. In the “Aeneid,” Palinurus, the old helmsman of Aeneas, during a very dark night, was joined by Somnus. Since the sea was calm, Somnus persuaded Palinurus to rest as the ship would have kept its course without deviation. Hence, Palinurus fell asleep, and Somnus pushed him overboard.

For Romans, sleep was more than just a god to worship. Roman’s beliefs and Roman medicine were influenced by Hippocrates. Romans understood the value of sleep and its disorders as well. It is common to find in Latin writings some stories of patricians who at times were tormented by sleeplessness. As with the ancient Greeks, the Romans believed that dreams were divine in origin, representing the way in which the gods communicated their wishes to mortal people. Dream-oracles were common. They were places where people were induced to sleep in the hope of receiving a prophetic dream (dream incubation). A nice description of dreams is found in the “Commentary on the Dream of Scipio” by Macrobius. He described five categories of dreams:  the enigmatic dream, the prophetic vision, the oracular dream, the nightmare, and the apparition. Interestingly, he suggested that the latter two did not have prophetic significance. By contrast, nightmares were caused by “mental, physical distress, or anxiety about the future,” and the apparition may have represented hypnogogic hallucinations.

Sleep habits in Rome

Romans’ sleep habits, and their adorned rooms, are well described in poems and writings of Latin Roman authors and poets. The numerous archaeological excavations, and the discoveries of Pompeii and Herculaneum, have helped historians and archaeologists to trace the layout of the houses, the ornaments, and the Roman customs. Then, just as today, Romans were aware of the importance of having good sleep. Certainly, the wealthier the Romans were, the more attentive they were to the comfort of the bed and its environment. A well-known story stated that the emperor Augustus, after having heard that a debt-ridden senator used to sleep deeply, sent a servant to the town to buy the same mattress as the senator. The Emperor said, “The mattress on which a man full of debts was able to sleep peacefully, will certainly also let me sleep peacefully.” (“Culcita in qua homo aere alieno oppressus semper tranquille dormire potuit certe etiam mihi somnum conciliabit.”)

Culcita was the ancestor of our common mattress. The word culcita comes from coleus – sack or bag. It was used both to indicate the mattress and the pillow, which consisted of a cloth sack filled with hay, wool or feathers. However, the culcita was different according to the social classes. The richest people fell asleep on fine linen sacks with padding made of feathers from the most precious and delicate birds, while the Romans of the bourgeois class used to sleep on sacks of less valuable fabric, filled with soft herbs. Undoubtedly, the poor people who could not afford valuable culcita needed to sleep on canvas sacks filled with straw, hay or reed leaves. First descriptions of the mattress are found in the epigrams of Martial, in which mattresses of rich people were represented by sacks composed of feathers of swans in opposition to the plebs’ mattresses, which were stuffed with straw.

There were different beds. Lectus cubicularis was the traditional bed, lectus lucubratorius was used to study and meditate, and lectus triclinaris was used to eat. Lectus genialis were bigger beds, but matrimonial double beds were uncommon. Indeed, some authors suggest that patrician couples may have slept in different rooms. However, co-sleeping with a spouse or lover, according to Latin literature, may have occurred only in cases when the couple shared an emotional connection.

In the domus or villae, archeological evidence has shown that noble Romans used to sleep in the cubicula. The cubicula were the small rooms intended for bedrooms and were decorated with mosaics and paintings illuminated by the dim light of lanterns. Some historians believe that cubicula, especially in the early Roman period, were not only a place for resting, sleep, and sexual encounters, but also, in some cases, a place for literary activities and receptions (but probably only under special circumstances such as illness). Some archaeological materials seem to suggest also that at times, beds were used both for sleeping and dining. Interestingly, across literature, descriptions of murders and suicides are described in cubicula. In contrast, there were no bedrooms for poor people. They lived in little houses called insulae that were buildings with multiple floors composed of different flats called cenaculum. Often a family used to live in only one big room in which the bed was a parallelepiped of walled up and plastered bricks on which there was the mattress, a sack filled with dried vegetables.

All Romans, both rich and poor, traditionally woke early in the morning, sometimes before sunrise. Patricians may have stayed in bed longer, waiting for their servants for the morning ablution before the salutation matutina (morning greeting). After having spent the morning at the forum, Romans typically would retire to have a midday siesta. Evening sleep followed the customary dinner. Some sources suggest that nocturnal sleep was segmented sleep into two bouts divided by a period of wake used to meditate, study or carry out other activities.

As detailed, sleep practices varied during Greek and Roman times, but since early in history the importance of sleep was identified.

Dimitrios Kantas MD, and Valentina Gnoni, MD, PhD, are AASM International Assembly ambassadors. This article appeared in volume eight, issue two of Montage magazine.