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Huberman Lab

Essentials: Erasing Fears & Traumas Using Modern Neuroscience

Published November 6, 2025
View Show Notes

About This Episode

Andrew Huberman explains the neuroscience of fear, trauma, and post-traumatic stress, detailing the brain and body circuits that generate and maintain these states. He describes how the autonomic nervous system, HPA axis, and amygdala-based threat circuitry interact with memory and prefrontal narrative systems to create adaptive and maladaptive fear responses. The episode reviews behavioral therapies, drug-assisted psychotherapies, physiological breathing protocols, lifestyle factors, and certain supplements that can help extinguish and replace fearful and traumatic memories.

Topics Covered

Trauma Anxiety Autonomic nervous system Dopamine Mental health Neuroplasticity Psychedelic-assisted therapy Respiration HPA axis Exposure therapy

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Quick Takeaways

  • Fear is an emotion built from stress and anxiety but is distinct in that it is tied to specific threats and memories, while trauma occurs when fear becomes maladaptively embedded and reactivated inappropriately.
  • The autonomic nervous system, particularly the HPA axis and amygdala-based threat circuitry, generates both rapid and long-lasting components of the fear response that can reshape brain circuits over time.
  • Fears and traumas are learned through mechanisms similar to Pavlovian conditioning and can arise from either single intense events or the accumulation of many experiences.
  • Effective treatment of fear and trauma requires both extinction of the old fearful response and the active relearning of new, positive or neutral associations through narrative and experience.
  • Prolonged exposure therapy, cognitive processing therapy, and cognitive behavioral therapy work by detailed, repeated recounting of traumatic events, which progressively reduces physiological arousal and enables new narratives to form.
  • Ketamine-assisted and MDMA-assisted psychotherapies appear to help by altering emotional states during trauma recounting, allowing new associations to be mapped onto old traumatic memories.
  • Deliberately inducing brief, controlled physiological stress through specific breathing protocols may be a low-cost way to recalibrate threat responses when done safely and, ideally, with clinical support.
  • Regular, trusting social connection and general lifestyle factors like sleep and nutrition support the brain and body systems involved in recovering from fear, anxiety, and trauma.
  • Supplements such as saffron and inositol have human data supporting their ability to reduce anxiety, although they act indirectly on fear and trauma and should be timed thoughtfully relative to exposure work.

Podcast Notes

Introduction and overview of fear and trauma

Host introduction and scope of the episode

Andrew Huberman introduces the Huberman Lab Essentials format[0:00]
• Explains that Essentials revisits past episodes to extract the most potent, actionable science-based tools for mental health, physical health, and performance
Professional background of the host[0:00]
• States he is a professor of neurobiology and ophthalmology at Stanford School of Medicine

Main topics to be covered

Core subjects: neuroscience of fear, trauma, and post-traumatic stress disorders[0:19]
• Says they will discuss neural circuits controlling fear and ways to extinguish fears using behavioral therapies, drug therapies, and brain-machine interfaces
Promised outcomes for listeners[0:32]
• Listeners will gain an understanding of the biology of fear and trauma and practical tools to confront fear and trauma

Framework for the episode

First component: biology of fear and trauma[1:02]
• He will explain cells, circuits, connections, and chemicals that produce the fear response and why fear sometimes becomes trauma
Biology of fear unlearning (extinction)[1:02]
• Emphasizes we cannot simply eliminate fears; they must be replaced with a new positive event or memory

Defining fear, stress, anxiety, and trauma

What fear is as an emotion

Fear as a nervous system phenomenon and emotion[1:33]
• Describes emotions as including bodily responses like heart rate changes and shifts in blood flow, leading to sensations of warming or cooling of the skin
• Notes a cognitive component: thoughts and memories that, combined with bodily changes, constitute an emotion

Clarifying what fear is not

Relationship between stress and fear[2:25]
• Defines stress as a physiological response
• States we cannot have fear without several or all elements of the stress response, but we can have stress without fear
Relationship between anxiety and fear[2:49]
• Defines anxiety as typically being stress about some future event, though it can mean other things
• Says we cannot really have fear without observing some elements of anxiety, but we can have anxiety without fear

Defining trauma operationally

How trauma builds on fear[3:45]
• Defines trauma as a fear event (including stress and anxiety) that becomes embedded or activated in the nervous system
• Trauma manifests when fear responses show up at maladaptive times and get reactivated inappropriately

Simplifying the conceptual landscape

Narrowing focus to fear and trauma[3:45]
• He lists multiple overlapping terms (stress, anxiety, trauma) and says he will focus on fear and trauma as they relate to specific biological and cognitive processes
• Aim is to dissect how fears are formed, unformed, and how new memories can replace previously fearful experiences

Autonomic arousal and the HPA axis

Autonomic nervous system overview

Two branches of the autonomic nervous system[5:43]
• Introduces autonomic arousal as a key concept tied to the autonomic nervous system
• Explains the sympathetic autonomic nervous system is not about sympathy but about increasing alertness
• Explains the parasympathetic branch as the calming system, involving cells, neurons, and chemicals that reduce arousal
Seesaw relationship between sympathetic and parasympathetic systems[6:17]
• Describes them as acting like a seesaw adjusting overall alertness, with many aspects but highlights the HPA axis as especially important

Structure and function of the HPA axis

Components of the HPA axis[6:34]
• Defines HPA axis as hypothalamic-pituitary-adrenal axis
• Hypothalamus: deep brain region controlling temperature, sex drive, hunger, thirst, and their inhibition
• Pituitary: located near the roof of the mouth, releases hormones into the bloodstream
• Adrenals: two glands above the kidneys that release hormones such as adrenaline (epinephrine) and cortisol
How the HPA axis controls arousal[7:58]
• Hypothalamus can trigger or prevent release of hormones like cortisol or hormones that stimulate the adrenals
• Adrenal hormones adrenaline and cortisol are called stress hormones but also participate in normal waking from sleep
• HPA axis is a three-part system that lets the brain wake up the body quickly and give arousal a long-lasting "tail" before it shuts off

Relevance of HPA axis to fear and trauma

Fast and slow components of fear responses[8:43]
• Notes that fear and trauma are characterized by long-lasting responses, even when triggering events are brief
• Explains that fast and longer-lasting HPA chemicals allow brief events to produce extended fear responses
Feedback to the brain and gene expression[9:10]
• States that longer-lasting components of the HPA response can feed back to the brain and control gene expression, taking many days
• Over time, this can build new circuits and chemicals that embed fear in brain and body

Amygdala and threat reflex circuitry

Role of the amygdala in threat responses

Amygdala as part of the threat reflex[9:35]
• Identifies the amygdala as an almond-shaped structure on both sides of the brain
• Describes it as part of the "threat reflex" generating quickened heart rate, hypervigilance, and increased access to energy
• States the amygdala is the final common pathway essential for the threat response

Amygdaloid complex and its inputs

Complex organization of the amygdala[10:21]
• Explains the amygdala is part of a larger amygdaloid complex with 12-14 areas depending on neuroanatomist
• Says it is not just a threat area but a generator of threat reflexes that integrates many information types
Inputs from memory and sensory systems[10:45]
• States that memory systems like the hippocampus and sensory systems (vision, hearing, smell, taste, touch) project into the lateral amygdala

Amygdala outputs and their significance

Output to hypothalamus and adrenals[11:12]
• One main output pathway goes to the hypothalamus and then to the adrenals to create alertness and readiness for action
Output to dopamine and reward systems[11:57]
• Another main pathway projects to the dopamine system, including the nucleus accumbens and mesolimbic reward pathway
• Recalls from prior dopamine discussions that these circuits underlie pursuit, motivation, reward, and craving
• Emphasizes that the threat center can activate the dopamine system, a point that will be important for using dopamine to wire in new memories to replace fearful ones

Prefrontal cortex and top-down control of fear

Top-down processing and narrative

Prefrontal cortex as a controller of reflexes[12:24]
• Introduces a fourth component of fear circuitry: prefrontal cortex and its subdivisions in the front of the brain
• Defines top-down processing as the way prefrontal cortex can control or suppress a reflex through deliberate decisions (e.g., "even though I don't want to, I'm going to do it anyway")
Attaching meaning and purpose to fear[12:45]
• Says this component allows narrative, meaning, and purpose to be attached to a generic fear response
• Notes there is no negotiating what fear feels like; only what it means and whether one persists, pauses, or retreats

Adaptive role of fear and when it becomes maladaptive

Initial question of how to eliminate fear

Limitations of simply eliminating fear[14:00]
• Acknowledges audience desire to eliminate fear but says it's not that simple, even with understanding of circuitry

Fear as an adaptive protective response

Why we need fear[14:06]
• States that in many cases fear is adaptive and should not be eliminated because it protects from injury or death
• Explains the threat response exists to prevent immediate harm and to protect us in the future via anticipation

Memories as protective vs dangerous

Protective fear memories[15:20]
• Some fear-evoking memories are protective because they help avoid mistakes that could cause serious harm
Dangerous fear memories[15:20]
• Other memories are dangerous when they create discomfort that limits behavior in maladaptive ways, such as impairing relationships or self-relationship
Fear circuitry as a memory system[16:36]
• Describes much of the fear system as a memory system designed to embed memories of past experiences so that the threat reflex can be activated in anticipation

Learning fear: Pavlovian conditioning and one-trial learning

Classical (Pavlovian) conditioning basics

Pavlov's dog example[16:39]
• Describes original experiments: bell does little by itself; bell paired with food leads dog to salivate to food; after repeated pairings, bell alone causes salivation
Conditioned vs unconditioned stimuli[16:47]
• Defines unconditioned stimulus as something that elicits a response without prior learning (food in example)
• Defines conditioned stimulus as the neutral cue (bell) that, after pairing, comes to elicit the response on its own

Application of conditioning to fear systems

Fear circuitry set up for rapid learning[18:03]
• States fear systems operate like classical conditioning but often require only "one-trial learning" rather than many pairings
• Says the circuit involving the amygdala and threat reflex is designed to learn and anticipate problems for safety
Example of performance-related fear[18:54]
• Gives example of a child freezing during a piano recital, feeling shame, and then avoiding instruments or public performance unless they overcome it

Temporal components and generalization of fear

Temporal backtracking of fear associations[18:54]
• Explains that fear systems can backtrack across time and link many events to one specific fear, or one incident to a broad general fear
Example of single negative event generalizing broadly[17:54]
• Tells story of a friend whose car was broken into in San Francisco, leading them to decide never to return to the city
• Uses this to illustrate how an isolated incident can color one's view of an entire place

Behavioral therapies for fear and trauma

Overview of behaviorally based treatments

Need for both extinction and replacement[21:06]
• States that fear or trauma cannot simply be extinguished; a fearful or traumatic memory must be both extinguished and replaced with a positive response
• Notes this replacement requirement is rarely emphasized in scientific or general discussions of fear and trauma

Three main language-based therapies

Prolonged exposure therapy, CPT, and CBT[21:51]
• Identifies three talk-therapy approaches shown to reduce fear and trauma: prolonged exposure therapy, cognitive processing therapy (CPT), and cognitive behavioral therapy (CBT)

Mechanisms of exposure-based and cognitive therapies

Detailed recounting of trauma and physiological response

Initial high anxiety during first recounting[22:02]
• Reports that when people first recount trauma in rich detail, physiological anxiety (heart rate, flushing, trembling) can be as great or greater than during the original event
• Emphasizes these recountings are done with a clinician present because of their intensity
Importance of rich, detailed narrative[22:48]
• Patients are encouraged to speak in complete sentences and provide detailed descriptions of internal feelings and memories before, during, and after the event

Progressive reduction of physiological arousal

Anxiety amplitude decreases with repetition[23:28]
• States that with second, third, fourth retellings, the amplitude of physiological anxiety becomes progressively diminished
Clinician consensus on detailed recounting[23:39]
• Says every clinician he consulted agreed that detailed recounting of traumatic events is essential for prolonged exposure, CPT, and CBT to work
Key role of recognition and repetition[23:55]
• Summarizes that recognizing the trauma in detail, repeatedly, is key to forming a new non-traumatic association with the event or person

Need to relearn a new narrative

Why extinction alone is insufficient[25:00]
• Explains that after diminishing the old response, one must relearn a new narrative or association to fully modify fear or trauma
Dopamine pathway involvement in relearning[24:42]
• Links this need to the amygdala's outputs to dopamine and reinforcement pathways, which allow fear circuits to be mapped onto positively associated experiences
Importance of narrative and rationalization[26:06]
• Argues that narrative and rationalization are often undervalued, but prefrontal cortex provides the capacity to attach meaning and purpose to otherwise reflexive responses

Accessing these therapies

Seeking licensed clinicians[25:31]
• Mentions people can look up licensed clinicians who provide prolonged exposure therapy, CPT, and CBT for fear and trauma relief

Self-directed work and role of social connection

Informal approaches to working through fear and trauma

Non-traditional methods some people use[25:48]
• Notes that many people without access to clinicians work through difficult experiences via journaling, talking to friends, or other non-traditional approaches

Importance of social connection

Social connection's impact on fear and trauma circuits[26:12]
• States that one key factor for everyone is the importance of social connection as it relates to chemical systems and neural circuits of fear and trauma
• Says regular, trusting social connection of any kind is very beneficial for working through fear and trauma

Drug-assisted psychotherapies: ketamine

Emerging drug treatments for PTSD

Focus on ketamine- and MDMA-assisted psychotherapy[27:36]
• Introduces ketamine-assisted psychotherapy and MDMA-assisted psychotherapy as emerging treatments for PTSD

Ketamine-assisted psychotherapy

Ketamine as a dissociative antidepressant[28:36]
• Describes ketamine as a dissociative antidepressant
Dissociation and its role in therapy[28:07]
• Defines dissociation as viewing what is happening from a different perspective than one normally would
• Says ketamine appears to allow patients to recount trauma while feeling none or a very different set of emotions than during the original event
Remapping new feelings onto old narratives[3:28]
• Characterizes ketamine-assisted psychotherapy as remapping new feelings onto old traumatic narratives while staying within the same narrative content
• Relates this to diminishing intensity of old trauma (extinction) and automatically building a new narrative and new experiences
Current status and limitations[2:49]
• Notes ketamine-assisted psychotherapy is spreading, with many clinics now offering it
• Reports psychiatry colleagues believe it is unlikely to be the ultimate treatment for trauma and fear, though it benefits some, especially those with combined trauma and depressive symptoms

Drug-assisted psychotherapies: MDMA

MDMA pharmacology and subjective effects

What MDMA is[30:19]
• Identifies MDMA as a powerful synthetic drug also known as ecstasy or molly in recreational contexts
• Says MDMA creates a brain and body state unlike typical conditions
Neuromodulator systems involved[30:42]
• Lists neuromodulators dopamine, serotonin, acetylcholine, and norepinephrine as key systems in the brain
• Notes a "seesaw"-type relationship between dopamine (pursuit, motivation, reward) and serotonin (pleasure and satisfaction with present resources)
Unique dual elevation of dopamine and serotonin[31:29]
• States that MDMA produces very large increases in both dopamine and serotonin simultaneously, a combination not seen under normal conditions
Subjective feelings under MDMA[31:46]
• Reports that people in therapeutic settings describe immense feelings of connection or resonance with people or even objects

MDMA-assisted psychotherapy for trauma

Mechanism in relation to fear circuitry model[32:40]
• Suggests MDMA may allow very fast relearning where new associations are attached to previously traumatic experiences
• Connects this to the same model: diminishing the old experience (extinction) and relearning a new narrative, similar to non-drug approaches

Recalibrating the threat system with breathing-based stress

Threat system overactivation in PTSD and chronic stress

How minimal cues can trigger threat responses[32:41]
• Explains that with trauma, PTSD, and extreme or chronic stress, the threat system becomes so ramped up that very little-sometimes just a memory or unknown association-is required to trigger it

Conventional approaches to lowering arousal

Typical pharmacological strategy[33:02]
• States that most typical drug approaches aim to suppress internal arousal, simply bringing overall stress down

Cyclic hyperventilation protocol as deliberate stress

Description of the breathing protocol[33:12]
• Describes a protocol of cyclic hyperventilation: about five minutes per day of stress-inducing breathing
• Involves repeated deep inhales and exhales (inhale, exhale) with inhale through the nose and exhale through the mouth
• Every 25-30 breaths, one performs a full exhale and then holds the breath with lungs empty for about 25-30 up to 60 seconds before resuming
Physiological effects and subjective experience[34:28]
• Reports that subjects and data show this increases autonomic arousal; he notes feeling it himself from a brief demonstration during recording
• People feel heating, sweating, wide eyes, and agitation-signs of adrenaline release and stress

Potential use of deliberate stress in trauma work

Concept of short daily stress bouts for recalibration[35:21]
• Envisions a short, two-week intervention where people, with clinician support, deliberately induce physiological stress for five minutes a day
• Proposes possibly pairing this breathing with recounting traumatic or fearful circumstances
Contrast with drug-assisted and narrative-only therapies[34:49]
• Emphasizes this is very different from ketamine-assisted, MDMA-assisted, or purely narrative-based psychotherapy states
Advantages and cautions[35:25]
• Highlights that such breathing interventions are low or zero cost and could be self-directed (for example, combined with journaling)
• Expresses belief that deliberate, self-directed entry into short bouts of stress is promising
• Warns people with anxiety or panic disorders to be very cautious and probably avoid this practice, and recommends ideally doing it with clinician support

Lifestyle and supplement factors influencing fear, anxiety, and trauma

Foundational lifestyle elements

Basic supports for mental and physical health[36:06]
• Says there are many things everyone can and should do to support mental and physical health, including quality nutrition and regular, ample sleep

Supplements with evidence for anxiety reduction

General framing of supplements in this context[36:25]
• Explains he will mention a few supplements some people find beneficial, while emphasizing they are indirect supports mainly focused on reducing anxiety overall
Saffron for anxiety[37:04]
• States there are 12 human studies indicating orally ingested saffron at 30 mg is a reliable dose for reducing anxiety on standard inventories such as the Hamilton Anxiety Rating Scale
• Notes these studies included both male and female subjects, some were double-blind, and a meta-analysis supports saffron's anxiolytic (anxiety-reducing) effects
Inositol for anxiety symptoms[37:32]
• Says inositol has been shown to produce a notable decrease in anxiety symptoms in human studies
• Mentions the dose used is relatively high-18 grams of inositol taken for a full month-and that it takes time for anxiety improvements to appear
• States the potency of inositol's effect is on par with many prescription antidepressants
Timing considerations relative to exposure work[39:00]
• Advises that by the logic already discussed, one would likely not want to take such anxiolytics right before sessions where the goal is to amplify intensity of an experience to extinguish it
• Suggests they might instead be used outside those sessions as a way to help bring the system back to baseline

Summary and closing guidance

Recap of biological pathways

Circuits underlying fear and trauma[38:35]
• States they reviewed pathways in brain and body underlying the fear response, chronic fear, trauma, and PTSD, including how these circuits embed fear

Overview of treatment approaches discussed

Range of clinical and self-directed tools[39:34]
• Mentions they covered a variety of approaches: behavioral therapies, drug-assisted psychotherapies, breathing-based self-directed practices, and supplements and lifestyle factors

Value of understanding circuit logic

Using circuit knowledge to choose treatments[38:53]
• Argues that understanding the logical structure of fear and PTSD circuits helps individuals think about which treatments and approaches make the most sense for them
Encouragement to lean into safe re-exposure[39:00]
• Hopes this understanding will help people lean into re-exposure practices, done in psychologically and physically safe, supportive environments
Relevance for subclinical fears and traumas[39:23]
• Acknowledges many people carry fears or traumas that are not at extreme clinical levels and may explore self-directed practices he outlined

Lessons Learned

Actionable insights and wisdom you can apply to your business, career, and personal life.

1

Fear is a necessary, adaptive system built from stress and anxiety, and the real challenge is distinguishing protective fear memories from those that unnecessarily limit behavior and well-being.

Reflection Questions:

  • • What recurring fears in my life clearly protect me from genuine harm, and which ones mainly prevent me from pursuing important goals or relationships?
  • • How could I begin to map out situations where my fear response feels disproportionate to the actual risk involved?
  • • What is one specific context this week where I can pause, notice my fear response, and consciously ask whether it is protective or unnecessarily constraining?
2

Effective fear and trauma work requires two steps: first extinguishing the intensity of the old fear response, and then actively wiring in new, more adaptive narratives and associations.

Reflection Questions:

  • • In a fear or painful memory I'd like to change, what would count as 'extinguishing' the old response versus what would count as building a new narrative?
  • • How might I safely and repeatedly revisit a difficult memory (e.g., in writing or with a trusted person) in a way that gradually reduces my physiological arousal?
  • • What positive or neutral experiences and meanings could I intentionally pair with that memory to start replacing the old association?
3

Detailed, repeated recounting of traumatic or fearful events in a supportive context gradually reduces physiological arousal and opens the door for new interpretations and behaviors.

Reflection Questions:

  • • What difficult experience in my past have I only ever described vaguely, without really going into detail even to myself?
  • • How could I create a safe container-through therapy, journaling, or a trusted friend-to start telling that story in fuller detail over time?
  • • When I imagine telling that story multiple times, what changes in my bodily sensations, emotions, or beliefs do I hope to see after several repetitions?
4

Top-down narrative and meaning-making from the prefrontal cortex can powerfully modulate automatic threat reflexes, transforming an unavoidable feeling of fear into a more constructive decision about whether to persist, pause, or retreat.

Reflection Questions:

  • • In recent situations where I felt fear, what story was I telling myself about what that fear meant and what I had to do?
  • • How might reframing my internal narrative-about what the fear signals and what options I truly have-change my choices in similar situations?
  • • What is one current challenge where I can deliberately separate the raw feeling of fear from my interpretation of it and experiment with a different story?
5

Brief, deliberate exposure to controlled physiological stress (such as structured breathing protocols) may help recalibrate an overactive threat system when used thoughtfully and, where possible, with professional guidance.

Reflection Questions:

  • • How do I currently react to even mild stress in my body, and do I tend to avoid or lean into those sensations?
  • • In what low-stakes setting could I safely experiment with a short, controlled stressor (like a brief breathing exercise) to observe and learn from my body's response?
  • • What boundaries or safeguards would I need-especially if I have high anxiety-to ensure that any self-directed stress practice remains safe and constructive?
6

Supportive social connection, sound sleep and nutrition, and targeted anxiety-reducing tools (like certain supplements) create a physiological backdrop that makes it easier to process fear and trauma effectively.

Reflection Questions:

  • • Where in my life do I already have reliable, trusting social connections, and how could I involve them more in my healing or growth processes?
  • • How might improving one foundational habit-such as sleep regularity or nutrition-change my baseline capacity to handle stress and anxiety?
  • • What is one concrete step I can take in the next week to strengthen my support system or daily routines so that I'm better resourced to work with difficult emotions?

Episode Summary - Notes by Charlie

Essentials: Erasing Fears & Traumas Using Modern Neuroscience
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