REM sleep


REM (Rapid Eye Movement) sleep is a crucial stage of sleep associated with several vital functions:

  1. Emotional Processing and Stability:

    • REM sleep plays a significant role in emotional and cognitive health. It helps remove irrelevant emotional connections, aiding emotional stability and resilience 1.
    • Lack of sufficient REM sleep has been linked with increased emotional instability, and an increased likelihood of psychiatric disorders 2.
  2. Cognitive Functions and Memory:

    • During REM sleep, cognitive processes can remain active, as demonstrated by studies where individuals respond to questions in their sleep 3.

      REM Sleep and Emotional Stability

      Andrew explains how REM sleep is crucial for eliminating the meanings that don't matter and uncoupling the potential for emotionality between various experiences. He draws parallels between the elimination of connections between things during REM sleep and some clinical practices designed to eliminate emotionality and help people move through trauma and other troubling experiences.

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      Understanding and Using Dreams to Learn and to Forget | Huberman Lab Podcast #5
    • REM sleep contributes to the elimination of unnecessary connections and the reinforcement of important ones, aiding memory and learning 4.
  3. Physical and Mental Health:

    • There's a linear relationship between the duration of REM sleep and longevity, as evidenced by large studies showing that reduced REM sleep is correlated with higher mortality rates 2.
    • Research indicates that REM sleep can act as a defense against paranoia, hallucinations, and psychosis, highlighting its protective effects on mental health 5.
  4. Dreaming and Sensory Experience:

    • REM sleep is characterized by intense brain activity that parallels waking consciousness, contributing to the vividness of dreams. It involves complete muscle atonia, preventing movement during vivid dreams 6.

Overall, REM sleep is fundamentally essential for emotional regulation, cognitive clarity, overall health, and the processing of daily experiences.



QQRT stands for Quantity, Quality, Regularity, and Timing, which are the four key elements of good sleep according to Dr. Matthew Walker. These four components are crucial for understanding and improving sleep:

  1. Quantity: Refers to the total amount of sleep you get, usually recommended between 7 to 9 hours for adults.
  2. Quality: Measures how uninterrupted and deep your sleep is. Quality is about having fewer awakenings and high sleep efficiency.
  3. Regularity: Consistency of your sleep schedule, sleeping and waking up at the same times daily.
  4. Timing: Aligns your sleep pattern with your biological clock or chronotype, ensuring that you sleep when your body is naturally predisposed to rest.

Dr. Walker emphasizes that all these factors interplay to determine sleep efficacy, influencing both mental and physical health 1.

Sleep Quality Essentials

Matthew explains the four key elements of good sleep: quantity, quality, regularity, and timing. He emphasizes that quality sleep is not just about hours slept but also about sleep continuity and efficiency, with a healthy sleep efficiency score being crucial for overall well-being.

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Dr. Matthew Walker: The Biology of Sleep & Your Unique Sleep Needs | Huberman Lab Guest Series

Are there any recent studies on the gut-brain axis?


Recent discussions on the gut-brain axis have indeed highlighted some fascinating insights. In a recent episode, Dr. Charles Zuker discussed how the brain can create contextual associations that lead to physiological changes, such as the anticipatory release of insulin in response to familiar stimuli (1). The main highway facilitating this communication between the body and the brain is through the gut-brain axis, primarily via the vagus nerve. This nerve plays a crucial role in monitoring organ functions and relaying signals between the gut and the brain, affecting metabolism, physiology, and even brain functions like emotions and cravings (1).

Moreover, Dr. Diego Bohórquez elaborated on the more direct line of communication between the gut and the brain that goes beyond hormonal pathways. He described how specialized cells in the gut can detect the external environment and rapidly communicate with the brain (2). His answer underscores a broader perspective that considers the gut not merely as a passive participant in digestion but as an active player in neurological health and disease.

These insights underscore the gut-brain axis's complexity and its influence over broader physiological and psychological states, from metabolic functions to moods and decision-making processes.

Gut-Brain Axis

Charles explains how the brain can create associations and send signals to the body, specifically the pancreas to release insulin in response to a smell. He also talks about the gut-brain axis and how the brain ultimately appears to be the conductor of the orchestra of physiology and metabolism.

Huberman Lab

Dr. Charles Zuker: The Biology of Taste Perception & Sugar Craving | Huberman Lab Podcast #81