From the Guidelines
Patients experiencing sleep paralysis are in a state of consciousness that is between sleep and wakefulness, not fully conscious in the normal sense, as they are aware of their surroundings but may experience hallucinations and paralysis. This condition occurs when the brain awakens from REM sleep while the body remains in a state of muscle atonia, which is a normal mechanism to prevent acting out dreams. The patient's experience of only feeling fully awake after the episode ends is consistent with sleep paralysis, as described in the context of narcolepsy and other sleep disorders 1.
During sleep paralysis episodes, individuals often retain some awareness of their surroundings but may experience dream-like hallucinations overlaid on reality, creating a confusing semi-conscious state. This occurs because parts of the brain responsible for dream imagery remain active while other areas begin to process real environmental stimuli. Key characteristics of sleep paralysis include:
- Awareness of the surroundings
- Hallucinations
- Paralysis
- Confusing semi-conscious state
Management of sleep paralysis typically includes:
- Improving sleep hygiene
- Maintaining regular sleep schedules
- Avoiding sleep deprivation
- Medications like selective serotonin reuptake inhibitors for frequent or severe episodes
- Cognitive behavioral therapy to reduce anxiety about these episodes. Understanding that sleep paralysis is generally harmless and common can help reduce the distress associated with these experiences, as it affects up to 8% of the general population. In the context of narcolepsy, sleep paralysis is one of the symptoms, along with cataplexy, hypnogogic/hypnopompic hallucinations, and fragmented sleep, as discussed in the diagnosis and management of sleep disorders in Prader-Willi syndrome 1.
From the Research
Sleep Paralysis and Consciousness
- Patients experiencing sleep paralysis are conscious during episodes, but their state of consciousness is a "mixed" state, combining elements of rapid eye movement sleep with elements of wakefulness 2.
- During episodes of sleep paralysis, the sufferer awakens to rapid eye movement sleep-based atonia combined with conscious awareness, which is usually a frightening event often accompanied by vivid, waking dreams (ie, hallucinations) 3.
Awareness During Sleep Paralysis Episodes
- The patient's realization that they are awake only after the episode is over suggests that their awareness during the episode may be altered or limited 3.
- The exact nature of consciousness during sleep paralysis is not fully understood and requires further research to disentangle the direction of effects and better capture associated features such as hallucinations, fear, and distress 2.
Clinical Features of Sleep Paralysis
- Sleep paralysis is often accompanied by fear and distress, and can be a complex and multisensorial experience, with vivid hallucinations of other people and entities being common 4.
- A systematic review of variables associated with sleep paralysis found that a number of factors, including substance use, stress and trauma, genetic influences, physical illness, personality, and sleep problems, are associated with the frequency and intensity of sleep paralysis episodes 5.