Uncanny Sleep: Unknown Dangers And What You Can Do

Sleep is a vital part of our lives, taking up around a third of our time on earth. But what happens when we're asleep, and can we really make the most of this time? Research shows that sleep is far from a passive activity, with our brains and bodies remaining remarkably active. From reinforcing existing memories to making money, there are many ways to be productive while you sleep. So, if you're looking to optimise your time in bed, read on for some tips and tricks to get more done while you snooze.

Sleep-related eating, where people get out of bed and eat without waking up

Sleep-related eating disorder (SRED) is a parasomnia condition characterised by unusual eating behaviours during sleep. People with SRED sleepwalk and eat without remembering the event afterward. Most people with SRED have an episode of eating nearly every night, and these episodes tend to occur even though the person is not hungry or thirsty.

People with SRED tend to prefer thick, sugary, and high-calorie foods such as peanut butter or syrup. The foods consumed during sleep-related events may be ones that the person does not normally enjoy. During a sleep-related eating episode, the person eats very quickly, and the entire episode may last for only ten minutes, including the time it takes to get out of bed and back. The person may also handle food sloppily and may or may not prepare hot or cold foods properly. There is a risk of injury during an episode, for example from handling knives and utensils, starting a fire, or getting burns from careless cooking.

SRED may develop slowly over time or begin quickly with nightly episodes of eating from the start. It is long-lasting and does not seem to ease up over time. It may be a factor in causing depression due to a sense of shame and failure to control the eating. Some people with SRED may avoid eating during the day or get too much exercise in an attempt to prevent obesity.

SRED can cause various problems, including eating strange forms or combinations of food, such as raw bacon, buttered cigarettes, or coffee grounds; eating or drinking toxic substances, such as cleaning solutions; eating foods to which one is allergic; insomnia due to sleep disruption; sleep-related injury; loss of appetite in the morning; excessive weight gain and obesity; and worsened control of diabetes.

SRED is more common in women than in men, with women representing about 65% to 80% of patients. The average age when it first occurs is between 22 and 29 years. SRED can develop on its own or result from the use of certain medications, particularly those used to treat depression and sleep problems. More than half of all people with SRED had another parasomnia before the onset of SRED, most commonly sleepwalking. Other sleep disorders closely linked to SRED include restless legs syndrome, periodic limb movement disorder, irregular sleep-wake rhythm, and sleep-related dissociative disorders. Other factors that may lead to the development of SRED include the use of certain medications, ending the habit of smoking, ending the abuse of alcohol or drugs, daytime dieting, daytime eating disorders, hepatitis (liver infection), and encephalitis (brain swelling).

If you suspect that you have SRED, the first step is to talk to a doctor, who will examine you and ask about your medical history. The doctor may also recommend keeping a sleep diary for two weeks to help identify your sleeping patterns. A sleep study called polysomnography may also be recommended to record your brain waves, heart rate, breathing, eye and leg movements, and any unusual behaviours during sleep.

Treatment for SRED typically begins with addressing underlying conditions and possible causes of symptoms. If medications are causing sleep eating, they may need to be stopped or changed. Other strategies for managing SRED include managing stress levels, locking the refrigerator or using an alarm on it, and practising good sleep hygiene. Safety measures are also important, such as putting locks on kitchen doors and cabinets, securely storing knives, and ensuring that the path from the bedroom to the kitchen is safe.

Sleep-related sexual behaviours, known as sexsomnia, where individuals display sexual vocalisations or intercourse while asleep

Sleep-related sexual behaviours, known as sexsomnia, are characterised by individuals engaging in sexual acts while in non-rapid eye movement (NREM) sleep. Sexsomnia is a distinct form of parasomnia, or abnormal activity that occurs while an individual is asleep.

During an episode of sexsomnia, an individual may engage in sexual intercourse, fondling, masturbation, pelvic thrusting, and spontaneous orgasm. They may also exhibit sexual aggression, or make sexual noises. Although their eyes may be open, giving the appearance of wakefulness, individuals experiencing sexsomnia are completely unconscious and unaware of their actions.

Sexsomnia is often first observed by a bed partner, roommate, or family member. It is more commonly diagnosed in males, and usually presents alongside other pre-existing sleep disorders, such as sleepwalking or sleep apnea. It can be triggered by physical contact, alcohol consumption, or other drugs.

Treatment for sexsomnia depends on the underlying cause, but often includes medication, improving sleep hygiene, and reducing stress or triggers. Benzodiazepines, such as clonazepam, are commonly prescribed. In cases where sexsomnia occurs alongside sleep apnea, the use of a continuous positive airway pressure (CPAP) device has been shown to result in the complete discontinuation of unwanted behaviours.

Sleep-related driving, where people drive a vehicle while unconscious

Sleep-related driving, or drowsy driving, is a dangerous phenomenon where a person operates a vehicle while suffering from sleep deprivation or fatigue. This can occur when a driver falls asleep with their eyes open, continuing to steer the vehicle without conscious awareness of their actions. This state is known as highway hypnosis, or 'white line fever', and it can lead to serious traffic accidents.

Highway hypnosis is characterised by a trance-like state, where a person's conscious attention is fully focused elsewhere, yet their brain continues to process information related to the road and vehicle control on a subconscious level. The driver may experience auditory and visual distortions, and their conscious attention may be fully occupied by another stream of thoughts while one stream remains focused on driving. This phenomenon is often associated with experienced drivers on familiar roads, as it allows them to drive in an automatic mode. However, it can also be triggered by various factors such as monotonous scenery, the flicker of lane markings, light glare, or driving alone.

Drowsy driving is a significant contributor to motor vehicle collisions. According to the National Highway Traffic Safety Administration (NHTSA), in 2017, drowsy driving led to approximately 91,000 crashes, 50,000 injuries, and 800 deaths in the United States. These numbers are likely underestimated due to the difficulty in determining whether drowsiness caused a crash, especially in fatal accidents. Other studies suggest that drowsy driving may cause up to 6,000 deadly crashes annually, with around 21% of fatal crashes involving a drowsy driver.

To avoid drowsy driving, it is crucial to prioritise adequate sleep, especially the night before a long drive. Additionally, avoiding alcohol and certain medications that cause drowsiness, as well as driving during peak sleepiness periods, can help reduce the risk of drowsy driving. It is also recommended to take breaks every few hours, even if not feeling tired, and to utilise caffeine or energy drinks as a short-term intervention. Passengers can also play a role by engaging the driver in conversation to help maintain their alertness.

Sleep talking, or somniloquy, where people make sounds or speak full phrases in their sleep

Sleep talking, or somniloquy, is a sleep disorder where people make sounds or speak full phrases in their sleep without being aware of it. Sleep talking can range from complicated dialogues or monologues to complete gibberish or mumbling. It is a common occurrence, with studies finding that up to 66% of people have experienced episodes of sleep talking, although it is usually a rare and short-lived event. Sleep talking is more prevalent in children and is believed to affect fewer adults. It occurs equally in women and men.

The exact cause of sleep talking is unclear, but it may be triggered by stress and mental health conditions. Sleep talking appears to occur more frequently in people with mental health issues, particularly post-traumatic stress disorder (PTSD). There is also evidence of a genetic component, with some studies finding that sleep talking can run in families.

Sleep talking is typically harmless and does not usually interfere with the sleep of the person doing it. However, it can cause problems for bed partners or roommates, interrupting their sleep and potentially leading to issues like insomnia or excessive daytime sleepiness. If the content of sleep talking is embarrassing, it may also create awkwardness or stress in the relationship.

For those wanting to limit or eliminate sleep talking, focusing on sleep hygiene may be beneficial. This includes maintaining a consistent sleep schedule, avoiding stimulants like caffeine, winding down before bed, getting regular exposure to daylight and physical activity, and creating a distraction-free sleep environment. Partners of sleep talkers can also try using earplugs or white noise machines to reduce the disruption.

Sleep starts, or hypnic jerks, where people experience a sensation of falling and jerk awake

Sleep starts, or hypnic jerks, are sudden, involuntary muscle contractions that occur when a person is falling asleep. They can be strong enough to jolt a person awake and are often accompanied by a sensation of falling.

Hypnic jerks are common, with up to 70% of people experiencing them at some point in their lives. They are typically harmless and not a cause for concern. However, they can be unsettling and disruptive to sleep. Certain factors may increase the likelihood of experiencing hypnic jerks, including:

• Caffeine and stimulant consumption: Stimulants such as caffeine and nicotine can disrupt sleep and increase the risk of hypnic jerks. It is recommended to avoid consuming caffeine late in the day and limit intake to no more than 400 milligrams per day.
• Vigorous exercise before sleep: While exercise is generally beneficial for sleep, vigorous exercise too close to bedtime may lead to hypnic jerks. It is advised to schedule intense workouts earlier in the day or opt for low- to moderate-intensity exercises at night, finishing at least 90 minutes before bedtime.
• Stress and anxiety: High levels of stress and anxiety can interfere with the ability to relax and prepare for sleep. Addressing stress and anxiety through relaxation techniques, such as meditation, deep breathing, or yoga, may help reduce the occurrence of hypnic jerks.
• Sleep deprivation: Lack of sufficient and regular sleep can contribute to sleep deprivation, which is a risk factor for hypnic jerks. Maintaining a consistent sleep schedule and practising good sleep hygiene can help prevent this.

While hypnic jerks themselves are typically not a cause for medical concern, they can be indicative of other sleep-related issues. If they are frequent and severe, they may lead to sleep-onset insomnia. Additionally, they can sometimes be mistaken for more serious conditions, such as myoclonic seizures or other movement disorders. Therefore, if hypnic jerks are causing distress or are accompanied by other symptoms, it is recommended to consult a healthcare professional.

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