Sleepwalking, medically known as somnambulism, is a common sleep disorder where a person performs complex actions, such as walking or talking, while remaining asleep. This behavior is classified as a parasomnia, involving undesirable physical events that occur during sleep. Public knowledge includes the persistent advice that you should never abruptly wake a sleepwalker. This raises a fundamental question: what is the underlying reason for this guidance?
The Brain State During Somnambulism
The scientific explanation for somnambulism lies in a state known as partial arousal, which occurs during Non-Rapid Eye Movement (NREM) sleep. Sleepwalking episodes arise from the deepest stage of sleep, typically NREM Stage 3 or slow-wave sleep, usually within the first few hours of the night. During this time, the brain experiences a dissociation where some areas are awake enough to control motor functions while others remain in a deep, unresponsive sleep.
The brain’s motor functions are partially activated, allowing the person to sit up, walk, or perform routine activities. Conversely, the areas responsible for consciousness, logic, memory, and executive function remain profoundly asleep. This leaves the sleepwalker “stuck” in a transitional state between full wakefulness and deep sleep. This dissociation explains why a person can navigate their environment with open eyes, remain unresponsive to external stimuli, and have no memory of the event afterward.
Addressing the Myth: Why Abrupt Waking is Discouraged
Common folklore suggests that waking a sleepwalker could cause severe medical trauma, such as a heart attack, but medical evidence confirms this is a myth. The true danger of abrupt waking is not physical shock, but the intense psychological and behavioral disorientation it triggers. When a person is forcibly pulled from deep NREM sleep, the sudden transition to full consciousness is extremely jarring.
This startling awakening can trigger a state of profound confusion, disorientation, and panic, sometimes referred to as a confusional arousal. The sleepwalker, suddenly finding themselves in an unexpected location with no memory of how they got there, may feel threatened. In this confused state, they may react with a fight-or-flight response, potentially lashing out defensively or attempting to flee.
Such reactions can lead to self-injury or injury to the person attempting the intervention. The advice to avoid abrupt waking is based on mitigating the risk of behavioral reactions and injury resulting from the sleepwalker’s disoriented state. Experts agree that the act of sleepwalking itself, which carries the risk of falls or leaving the house, is often more dangerous than the act of waking them.
Guidance for Safe Intervention
Since abrupt waking carries behavioral risks, the recommended response focuses on gentle intervention and safety. The safest strategy is to calmly and quietly guide the person back to bed without attempting to force a complete awakening. Anyone encountering a sleepwalker should avoid sudden movements, yelling, or physical restraint, as these actions can provoke a confused reaction.
It is best to speak in a low, gentle, and repetitive voice while softly steering the individual away from immediate hazards. If the sleepwalker is moving toward danger, the primary goal is to protect them by clearing obstacles or gently redirecting them from risks like stairs, windows, or sharp objects. If the sleepwalker is in immediate danger, a gentle, non-aggressive arousal may be necessary, but this should be done with minimal physical contact to reduce the chance of a defensive reaction.
Common Triggers and When to Seek Medical Help
Sleepwalking episodes are often precipitated by factors that disrupt the normal sleep cycle. Sleep deprivation is a primary trigger, as insufficient rest leads to an increase in deep slow-wave sleep, from which somnambulism arises. Stress, anxiety, and high fevers, particularly in children, are also common factors that can trigger an episode. Certain medications, including sedatives, antidepressants, and alcohol, are known to increase the likelihood of sleepwalking.
It is not necessary to seek medical treatment for occasional, non-violent sleepwalking episodes, especially in children, who often outgrow the condition. However, consultation with a sleep specialist is recommended when episodes become frequent (more than once or twice a week) or if the behavior involves dangerous actions or violence. If sleepwalking begins for the first time in adulthood or causes significant daytime fatigue, a medical evaluation can help rule out underlying conditions like sleep apnea or other neurological issues.