Glossary

Sleep is of much medical interest, which means that a number of specialist words and phrases have cropped up around it. You can find out what some of the most regularly used examples mean with this glossary.

Aromatherapy

The use of essential oils from flowers, trees and shrubs and their fruits, blooms, leaves, stems and roots to promote well-being and good health.

Essential oils are often added to a base oil such as almond oil and massaged into the body. They may also be added to steam inhalations or baths, added to compresses or spread throughout a room with diffusers.

Circadian rhythm

The internal biological clock which governs when we feel sleepy and awake.

Essential oils

Oils extracted from flowers, trees and shrubs and their fruits, blooms, leaves, stems and roots. They are obtained by steam distillation (passing steam through the plant material containing the desired oils), expression (squeezing the oil from peel), maceration (immersing the plant in hot oil to release the essence) or enfleurage (pressing flowers between oiled glass plates).

Chamomile

The dried flowers of the perennial herb Chamaemelum nobile, used as a homeopathic preparation to calm and counteract irritants.

Epworth Sleepiness Scale

This is used to determine your level of daytime sleepiness and give an indication as to whether you're getting enough sleep. Conclusions are based on answers to a set of specific questions designed to discover how likely you are to fall asleep in certain scenarios.

Insomnia

Insomnia refers to difficulty in getting to sleep or waking up and not being able to get back to sleep. In essence, insomnia is the disturbance of a normal sleep pattern.
Insomniacs can fall into one of 3 categories:
Transient: usually caused by external factors such as noise or temperature. This can last for 2-3 days.
Short Term: often related to emotions or illness and lasts more than a few days but less than 3 weeks.
Chronic: can be related to depression or stress and can be defined as suffering from disturbed sleep most nights for 3 weeks or longer.

Herbal remedy

The medical use of preparations containing only plant material. Herbal remedies for insomnia or sleeplessness include a variety of herbs such as valerian, passiflora, lemon balm and hops extract.

Hop

Herbaceous perennial vine of the family Moraceae (mulberry family), widely cultivated since early times for brewing purposes. The cone like mature female flowers, called hops, are borne on different plants from the male; their loose scales contain lupulin, a yellow resinous powder that is added to beer to impart a bitter flavour and is used medicinally as a tonic and soporific.

Melatonin

A hormone produced during the hours of darkness by the pineal gland in the brain. Has an influence on the circadian rhythm.

Non-REM sleep

Non-Rapid Eye Movement sleep - sleep made up of several stages leading in and out of deep sleep. It is during deep sleep when our body undergoes the repair/renewal and growth process.

Passiflora

Or Passion flower. Passiflora is a climbing plant, popular in gardens in Europe. It originates from South America and the East Indies. Passiflora is an anxiolytic which is calming by reducing tension and spasm in the muscles.

Pilates

A form of exercise invented by Joseph Pilates, pilates is a series of non-impact exercises designed to develop strength, flexibility, balance and inner awareness.

REM sleep

Rapid Eye Movement sleep - the period of sleep when we are most likely to dream. This type of sleep is associated with rapid sweeping movements of the eye under the eyelid and mild involuntary muscle jerks. Cycles of REM and Non-REM sleep happen throughout the night.

Serotonin

The hormone serotonin is a type of neurotransmitter. Neurotransmitters are chemicals that transmit impulses from one nerve cell to another. Melatonin is derived from serotonin.

Sleep

A natural state of rest. While you're asleep, your body goes through different stages at approximately 90 minute cycles. These include light sleep, deep sleep and dreaming.

Sleep apnoea

Apnoea means the cessation of breathing. Sufferers of sleep apnoea temporarily stop breathing while asleep. There are two types of apnoea - Obstructive Sleep Apnoea where the airway becomes blocked or Central Sleep Apnoea where the brain doesn't send the right signal to tell you to breathe when you're asleep. In both cases, sufferers will wake with a snore or snort. The condition can happen many times throughout the night meaning sufferers feel very sleepy the next day.

Sleep cycle

Term for our sleep pattern. The cycle is the passing between REM and Non-REM sleep. Each sleep cycle lasts about 90 minutes and we experience between 4 and 6 sleep cycles during a typical night's sleep.

Night terrors

Also known as sleep terrors. They occur during a phase of deep non-REM sleep as opposed to nightmares which occur during REM sleep, the dream phase of sleep. During a night terror, which may last anywhere from five to twenty minutes, the person is still asleep, although the sleepers eyes may be open. When the subject wakes up, they normally have no recollection of the episode other than a sense of fear.

Tryptophan

A naturally occuring amino acid derived from protein in food that is used to make serotonin.

Tai Chi

An ancient Chinese system of postures linked by elegant and graceful movements, aimed at balancing yin and yang and creating inner and outer harmony. It is said to improve nervous system function.

Valerian

A plant of the genus Valeriana, widely cultivated for its small, fragrant, white to pink or lavender flowers and for use in medicine as a sedative.