What is the cause for nightmares and sleep walking


Nightmares and sleepwalking are linked to various factors involving brain activity, sleep cycles, and the autonomic nervous system.

For nightmares:

  • Nightmares usually occur during REM (Rapid Eye Movement) sleep, when the brain is more active and dreaming is most likely. During this stage, our brains simulate scenarios that resemble reality. It's a time when the brain can form narratives from potentially random or sporadic stimuli, such as P waves from the brain stem that might impact the content or randomness of dreams 1 .

For sleepwalking:

  • Sleepwalking tends to occur during the deeper stages of sleep (non-REM, particularly stages 3 and 4), where the brain is less active. This is the period when the brain processes the day's experiences, decides which memories to keep, and integrates new information. Specific external stimuli, like smells or sounds, can even influence which memories are reinforced during this stage, demonstrating the brain's plasticity even in deep sleep 2 .

Additional factors contributing to these phenomena include:

  • The balance between various systems, such as the sympathetic (alertness) and parasympathetic (calmness), is crucial. This balance can be disturbed by lack of quality sleep, leading to dysregulation of the autonomic nervous system 3 .

    P Waves and Dreams

    Gina and Andrew discuss the origins and functions of P waves, which are excitatory events that come from the brain stem and project everywhere in the cortex. They also explore how P waves work together with spindles to cause plasticity and how they may be the underlying reason why REM sleep dreams are random.

    Huberman Lab

    Dr. Gina Poe: Use Sleep to Enhance Learning, Memory & Emotional State | Huberman Lab Podcast
  • Dietary choices, particularly in the evening, might influence the architecture of sleep. Consuming carbohydrates in the evening can increase serotonin levels, which are necessary to enter sleep. An imbalance in dietary intake can affect sleep quality and potentially disturb sleep, contributing to sleepwalking or nightmares 4 .

Moreover, supplementing with serotonin or its precursors for sleep can disrupt natural sleep architecture. Serotonin levels must be modulated precisely during sleep cycles, and this precise balance can be upset by supplementation, leading to vivid dreams or sleep disturbances like insomnia 5 .

These explanations underscore the complexities of brain function during sleep and the myriad factors that can disrupt its natural rhythms, potentially leading to nightmares or sleepwalking.