All about Sleep Terrors

Sleep terrors are most common in children between the ages of 3 and 8 and are estimated to occur in 1% to 6.5% of children. They are also known as night terrors. Night terrors are different to nightmares; nightmares happen at a different stage of sleep and affect both children and adults. Sleep terrors can be distressing to witness but are not usually cause for concern.

What are sleep terrors?

Sleep terrors are a type of sleep disorder characterised by a sudden, intense fear or terror that occurs during sleep. These episodes usually happen during the non-REM stages of sleep, particularly during the transition from deep sleep to lighter sleep, therefore sleep terrors usually happen in the earlier parts of the night. As you sleep, your brain cycles through four different stages of sleep. The first three stages are considered non-rapid eye movement (NREM) sleep. The fourth stage is rapid eye movement (REM) sleep, also known as active sleep. Each sleep stage has a different function in maintaining your brain’s overall cognitive performance.

During a sleep terror, the person may suddenly wake up with a sense of extreme fear, often accompanied by screaming, thrashing, jumping out of bed or other intense physical reactions. Their eyes may be open during a night terror but they are asleep. As the terror passes, the person may rouse from sleep and have no recollection of it the next morning. 

Night terrors and nightmares are different and happen at different stages of sleep. It’s rare to remember having a night terror. Nightmares are bad dreams you wake up from and can remember. A nightmare is usually a vivid and disturbing dream that can cause negative emotions, such as fear, anxiety or sadness and often involves scenarios that are frightening, threatening or unsettling. Nightmares usually occur during the rapid eye movement (REM) stage of sleep, which is a phase associated with intense dreaming. 

What causes sleep terrors?

Sleep terrors are a type of parasomnia. Parasomnia is a category of sleep disorders that involve either abnormal behaviour, movements, emotions, perceptions or dreams that occur while falling asleep, while asleep or during the arousal period in between sleep stages.

Examples of other parasomnias include:

• Night terrors.
• Nightmares.
• Rapid eye movement sleep behaviour disorder.
• Sleep-related eating disorder.
• Sleep-related groaning, also known as catathrenia.

Like other parasomnias, there is some evidence that sleep terrors may be genetic and are more likely to occur in individuals who have a family history of parasomnia.

Some other common causes of sleep terrors are:

• Being sleep deprived.
• Disruption of sleep schedule.
• Being unwell.
• Sudden loud noises when you are in a deep sleep.
• If you are stressed, anxious or worried or go to bed after something has frightened you.
• A child experiencing separation anxiety.
• A head injury.

In some cases, sleep terrors can also be caused by:

• Taking some medication, for example antidepressants.
• Some mental health conditions, for example post-traumatic stress disorder.
• Conditions that affect the brain, for example dementia.
• Having nocturnal asthma.

There are other conditions that affect sleep, such as restless legs syndrome or sleep apnoea. Restless legs syndrome is a type of sleep disorder that is characterised by an uncontrollable urge to move the legs, usually accompanied by uncomfortable sensations in the legs. People with restless legs syndrome often experience relief by moving their legs, which can involve activities such as walking, stretching or moving the legs. The symptoms typically worsen during periods of inactivity and can disrupt sleep, leading to difficulties falling asleep or staying asleep. Having the condition makes it more likely that someone would have sleep terrors. 

Obstructive sleep apnoea is a sleep disorder in which the airway becomes blocked, which causes short lapses in breath during sleep. These create sleep interruptions that make sleep terrors more likely. 

Night terrors are more common in people with family members who have had night terrors or who sleepwalk. Sleepwalking, also referred to as somnambulism, is a sleep disorder that affects a small percentage of the population. It is where someone walks around or carries out other activities while they are not fully awake. People can experience sleepwalking in different ways. Some people may just sit up in bed and have a look around; this may be brief and they may appear confused. Others may get out of bed and walk around, they may open cupboards, get dressed or even eat. Some sleepwalkers may present as being agitated. In extreme cases, the person may walk outside and carry out complex activities, such as driving a car. In these cases, sleepwalking can be dangerous. Often, the person will have little or no memory of what happened the following day. 

Who is affected by sleep terrors?

Night terrors can affect people of any age but are much more common in young children than in adolescents or adults. Most often, the episodes emerge when a child is between 3 and 8 years of age and usually resolve spontaneously by adolescence or puberty. Some studies, however, have shown night terrors occurring in younger toddlers more frequently than what has been previously understood. The prevalence of night terrors in children over 12 years old appears to be low. Most adolescents who have night terrors as a younger child will outgrow these episodes as they move into adulthood. 

Adults experience sleep terrors much less frequently than children and they are considered to be a rare occurrence in adulthood. Adults with a childhood history of night terrors may have a recurrence of the episodes. This could be triggered by stress, sleep deprivation or having another sleep disorder.

The impact of sleep terrors

Occasional sleep terrors are relatively common in children and often resolve on their own as they get older. Sleep terrors can, however, in some cases be unpleasant for the person experiencing them, or for the people who are witnessing them.

Sleep terrors can:

• Cause emotional distress – people who experience sleep terrors often report intense fear and panic during episodes. While they may not have a clear recollection of the sleep terror occurring, the emotional distress can still be felt upon waking in some cases.
• Make people fearful of falling asleep – some people who have sleep terrors may feel fearful of falling asleep. This can lead to sleep anxiety.
• Disrupt sleep – sleep terrors can disrupt normal sleep cycles, which can lead to fragmented and poor-quality sleep. This can result in daytime sleepiness, fatigue, and difficulties with concentration and memory.
• Impact on normal functioning – regular sleep terrors may impact on the person’s overall well-being and daily functioning. These sleep disturbances can contribute to mood changes, feeling irritable and difficulty coping with stress. Since sleep is heavily linked to emotional regulation, when sleep is restorative, we cope better with stress and can manage our emotions.
• Cause disruption to other members of the household – partners or family members may be disturbed by the person’s behaviour during sleep terrors.
• Cause safety concerns – sleep terrors can involve intense physical activity, for example thrashing around, screaming or attempting to escape perceived danger. This may pose a safety risk to the person experiencing the sleep terror and potentially to those around them.
• Impact the person’s mental health – persistent or extreme sleep terrors may contribute to the development or exacerbation of mental health conditions, which can include things like anxiety and depression. The quality and duration of sleep is known to directly impact mental health. With good quality, adequate sleep, people generally have better mental well-being. Poor sleep patterns usually contribute to more frequent bouts of depression, anxiety and other mental health problems. With consistently inadequate sleep, people are more at risk of developing a new mental health problem.

Treatment for sleep terrors

Most children outgrow sleep terrors without the need for any intervention. You should always speak to your healthcare professional if you are worried about your child’s sleep terrors, or if:

• Episodes occur more than twice a week.
• A sleepwalking episode results in an injury.
• You are worried that a sleep terror episode may result in an injury.
• Sleep terrors are accompanied by sleepwalking or sleep talking.
• Your child’s sleep terrors are causing sleep disruption or daytime sleepiness or problems functioning.
• Sleep terrors begin in an older child or as an adult.

In order to receive a diagnosis of sleep terrors, you will just be required to describe your or your child’s symptoms to your healthcare professional. If there are other symptoms present, other investigations may be necessary. For example, if your child has sleep apnoea, is bedwetting or having seizures further testing may be needed. A referral to a sleep specialist may be needed to rule out other sleep disorders or diagnose underlying health conditions. A sleep specialist specialises in diagnosing and treating sleep disorders. Sleep specialists are most often neurologists, pulmonologists or psychiatrists who have completed additional training in sleep medicine. 

Adolescents and adults who have repeated night terrors may benefit from working with a sleep specialist who can help to identify whether there is an underlying cause that can be treated. They may also recommend therapy in order to manage the symptoms of night terrors. 

Knowing how to respond to someone who is having sleep terrors will be beneficial in order to minimise the chances of the person having the sleep terror becoming more confused. Some people may be referred for a sleep study to further evaluate and diagnose underlying sleep disorders. You may be asked to keep a sleep diary and other members of the household may be asked for their input. 

Treatment is unlikely to be needed for children who experience sleep terrors less than twice per month. Most children will naturally outgrow the sleep terrors as they get older and their nervous system develops.

There are some things you can do in order to reduce the frequency of your or your child’s sleep terrors which can include:

• Getting enough sleep – sleep deprivation is thought to increase the likelihood of sleep terrors.
• Good bedtime routines – a consistent bedtime routine can contribute to better quality sleep overall. Establish a regular sleep schedule by going to bed and waking up at the same time every day.
• Trying to relax before going to bed – this may involve meditation, mindfulness, breathing exercises, having a warm bath or reading a book. Simple routines like these help to signal your body that it’s time to wind down ready for sleep.
• Avoiding caffeine and alcohol – lifestyle choices like excessive caffeine or alcohol consumption, particularly close to bedtime, means that people can experience shorter and poorer-quality sleep. If you are prone to sleep terrors, being more deprived of sleep can increase the chances of having a sleep terror. The effects of caffeine and alcohol on the nervous system can also contribute to an increased risk of having a sleep terror.
• Exercise – regular exercise can have several positive effects on sleep, and the relationship between physical activity and sleep is well-documented, including the regulation of circadian rhythms, reduction in anxiety and stress levels and enhanced melatonin production which is a hormone that regulates sleep-wake cycles.
• Getting outside – exposure to natural light during outdoor activities can also contribute to melatonin regulation.
• Thinking about your or your child’s sleep environment – ensure the sleep environment is conducive to rest, including a dark, quiet and cool room. You should also limit exposure to electronic devices, particularly before bedtime.
• Addressing any underlying stress and anxiety – if your child is struggling with their mental health, you should seek support for this from your healthcare professional. If your child has separation anxiety, there are ways you can support them with this. it is important that they feel safe when falling asleep. This often means staying with your child and comforting them to sleep.
• Scheduled awakenings – this technique involves waking the person before the usual time of night terrors, disrupting the sleep cycle to prevent the occurrence of night terrors.
• Keeping a sleep diary – keeping a sleep diary can help identify patterns and potential triggers for night terrors. This information can be useful when working with a healthcare professional in order to develop a tailored treatment plan.
• Medication – the use of medication for sleep terrors is rare but in some more extreme cases, medications may be considered for children who are having persistent sleep terrors. Some children respond to medication with sedatives and certain antidepressants.

During a sleep terror, you should keep calm, wait for the terror to pass and then gently settle the person back to sleep. 

The Sleep Charity offer information and support for anyone who is affected by a sleep issue.