Sleep Paralysis
Sleep paralysis occurs when a person wakes up and is conscious but unable to move. It is a disorder that causes significant distress, although it has no harmful effects on the body.
Symptoms and Causes
Sleep paralysis is a disorder that manifests when a person awakens but is unable to move or speak. During this period, the brain is conscious (wakefulness phase), but the muscles are paralyzed and cannot perform voluntary movements (REM sleep phase). Episodes, lasting from a few seconds to several minutes, are described as moments of intense distress in which the patient perceives everything around them but is unable to communicate that they are awake.
This type of parasomnia (abnormal behaviors during sleep or transitions to and from sleep) is often accompanied by disturbances in perception, thought, and emotional state. In other words, it is common for the inability to move to be associated with frightening visual, auditory, and tactile hallucinations.
Sleep paralysis is classified into two types, based on frequency:
- Isolated paralysis: occurs in sporadic episodes, usually associated with stress or sleep deprivation.
- Recurrent paralysis: occurs frequently and is often related to an underlying disorder.
Although sleep paralysis causes distress and concern, it is generally harmless and has a physiological explanation. It may represent a manifestation of a mental disorder, a sleep disorder, or the body’s inability to transition properly through the different stages of sleep.
Symptoms
Characteristic symptoms of sleep paralysis include:
- Inability to perform voluntary movements upon awakening or at sleep onset.
- Hypnagogic (falling asleep) and hypnopompic (awakening) hallucinations:
- Shadows
- Strange figures
- Unexplained noises
- Intruder paralysis: presence of a threatening figure in the room
- Incubus paralysis: pressure on the chest, often perceived as exerted by a foreign entity capable of aggressive acts
- Vestibular paralysis: sensation of leaving the body, rotating, or floating
- Respiratory difficulties
- Anxiety induced by hallucinations
- Panic attacks
Causes
The exact causes of sleep paralysis are unknown, although it is clear that it results from a temporary mismatch between the brain and body in different sleep phases. This phenomenon is often associated with the following circumstances:
- Sleep deprivation: more frequent in individuals sleeping 4–6 hours per day
- Poor sleep hygiene, including irregular sleep schedules
- Emotional or psychological stress
- Exposure to traumatic events
- Excessive consumption of alcohol or other harmful substances
- Sleeping in the supine position
- Insomnia
Risk Factors
Sleep paralysis is more common in patients with the following conditions:
- Narcolepsy: daytime sleepiness that can cause sudden sleep onset
- Bipolar disorder
- ADHD (attention-deficit/hyperactivity disorder)
- Panic disorder
- PTSD (post-traumatic stress disorder)
Complications
Sleep paralysis does not produce harmful effects on the body but can severely affect mental health and quality of life, often causing:
- Anxiety
- Depression
- Panic attacks
- Fear of sleeping
- Daytime sleepiness
Which Specialist Treats Sleep Paralysis?
Sleep paralysis is managed within the specialties of Neurology or Clinical psychology.
Diagnosis
The diagnosis of sleep paralysis is clinical and is based on the patient’s description of the episodes.
To rule out other pathologies, the specialist may perform a polysomnography, a sleep study that monitors bodily functions during sleep, including heart rate, respiration, and brain waves.
Treatment
There is no specific treatment for sleep paralysis, as it usually resolves spontaneously and does not cause physical harm. To prevent episodes, it is recommended to:
- Maintain regular sleep schedules
- Sleep 7–9 hours per night
- Practice meditation or relaxation exercises before bedtime
- Cognitive-behavioral therapy (CBT): a sleep specialist guides the patient to modify thoughts or behaviors that may trigger episodes. Techniques for relaxation, fear management, and establishing a proper bedtime routine are implemented.
When episodes are frequent and the resulting stress significantly affects the patient’s health, tricyclic antidepressants may be prescribed. If sleep paralysis is a symptom of an underlying disorder, targeted treatment of that condition is necessary.
