Andrew Huberman: How the Brain Works, Andrew’s Backstory, Scientific Literacy + More

Blood Flow Restriction Training

• Peter and Andrew discuss their experience with blood flow restriction (BFR) training
• Benefits of BFR training:
• Growth hormone increase
• Minimal soreness
• More metabolic benefit with less trauma
• Increased efficiency in processing lactate

Lactate and the Brain

• Lactate is an important fuel for the brain, especially in high-​​stress situations
• Hypothalamus and brainstem areas preferentially use lactate as a fuel
• Prefrontal cortex quiets down during high-​​stress situations, allowing resources to be allocated to more essential brain functions

Prefrontal Cortex and Rule Setting

• Prefrontal cortex is involved in rule setting by context
• Adjusting behavior depending on context is governed by the prefrontal cortex
• Phineas Gage: famous case of a man who lost his ability to switch rule sets due to damage to his prefrontal cortex

Amygdala and Fear

• Amygdala is involved in defense and alertness systems in the brain
• Bilateral amygdala damage can lead to a lack of fear in certain situations and inappropriate behavior
• Prefrontal cortex is intimately involved with the limbic pathway
  Monosynamics and Cortical Areas
• Monosynamics: less evolved than the neocortex
• Dating of cortical areas is controversial
• Arnold Krigstein at UCSF uses carbon dating to study brain evolution
• Establishing homology between species is difficult due to the lack of a fossil record for the brain

Prefrontal Cortex, Amygdala, and Insula

• Prefrontal Cortex: involved in executive function and complex rule setting
• Amygdala: involved in threat detection and generic responses (e.g., increased heart rate)
• Insula: controls interoception (perception of internal body states) and has a map of the body surface and internal organs

Neural Circuits and Direction of Information Flow

• Neural circuits can run in both directions
• Under calm conditions, information flows from the prefrontal cortex to the amygdala and insula
• Under stress or discomfort, information flows from the insula and amygdala to the prefrontal cortex
• This inversion of information flow can lead to a loss of flexibility in thinking and a focus on specific rule sets

Mental Health and Information Flow

• In states of mental health, information flows from the prefrontal cortex to the amygdala and insula
• In depression, there is a deficit in activation of the left dorsolateral prefrontal cortex, leading to information flow from the insula and amygdala to the prefrontal cortex
• This inversion of information flow may contribute to feelings of hopelessness and lack of motivation in depression
• People with limited rule sets struggle to access different ways of thinking 
  • Others may suggest exercise, job hunting, or new relationships, but these individuals can’t see the same “playboard”
• Nolan’s lab uses transcranial magnetic stimulation to activate left dorsolateral prefrontal cortex 
  • Helps reveal new rule sets in the moment
  • Likely overwhelms south-​​to-​​north current and creates neuroplasticity that reduces it over time
• Interoception: awareness of internal body states 
  • Double-​​edged sword: high levels can be beneficial, but also problematic
  • People with high interoception can often feel their own heartbeat
  • Insula plays a role in processing internal state information
• Pain perception and the insula 
  • Primary site for delivery of somatic sensation to the brain
  • Example: pain from a small bowel obstruction is perceived in the insula
• Importance of the brain in perception and experience 
  • Amputation of limbs would not change one’s identity as much as removing parts of the brain
  • Vision and movement dominate most of the brain’s real estate
  • 40–42% of the human brain has visual response specificity
• Comparing human senses to animals 
  • Humans have better vision than many animals due to tricolor vision
  • Animals often have superior hearing and smell capabilities
  • Olfactory neuronal component in humans is minimal in comparison to vision
    Visual Acuity and Adaptation in Animals and Humans
• Animals have different visual acuity and distribution of what they see in the world 
  • Example: Sheep have high acuity vision for select regions of visual space
  • Redtail hawks have a phobia that views the floor, allowing them to see prey from a distance
  • Diving birds have a horizontal visual streak to view the horizon
  • Sloths have a phobia on the top of the eye to view the jungle floor
  • Elephants have a J‑shaped high-​​density retina to view their trunk and its tip
• Retina and visual system are most sensitive to motion 
  • Fast pathway from retina to brainstem structure called the superior caliculus
  • Engages the orienting reflex, not a conscious decision-​​making process
• Humans have microsaccades (tiny jitter) in the retina that prevents habituation of neurons 
  • If microsaccades were eliminated, objects would become invisible unless there’s movement
• Olfactory adaptation: Smells become less noticeable over time due to habituation of olfactory neurons 
  • Example: Fish market smell becomes less noticeable after a few minutes
• Visual adaptation examples: 
  • Fun house mirror: At first, feel off-​​balance, but quickly adapt to the distorted environment
  • Inverting glasses: Within 4 hours, the brain adapts and flips the visual world back to normal 
    • Cellular changes in the oculomotor and visual motor structures of the brain stem communicate with higher-​​level perceptual centers of the cortex
• Primary function of the visual system was to recognize daytime and nighttime 
  • Melanopsin intrinsically photosensitive ganglion cells handle this function, not paying attention to shapes or other visual aspects
    Neurons and Sensing in the Brain
• Neurons in the brain can sense various aspects of the environment 
  • Daytime and nighttime (circadian biology)
  • Contrast and motion
  • Shape and form
  • Color
  • Specific facial features
• Fusiform face gyrus: area of the brain responsible for facial recognition 
  • Lesions in this area can lead to prosopagnosia, a condition where people can recognize faces but not specific facial identities

Color Vision and Olfaction

• Color vision evolved later in the visual system 
  • Humans traded out diversity of olfactory receptors for the ability to perceive a wider range of colors
• Olfaction is still important for humans 
  • Smell is closely linked to taste and can impact our physiology
  • Examples: the smell of a romantic partner, a child, or disgust from the smell of vomit

Pheromones and Odor Effects

• Pheromones: chemicals released by one organism that can act on the physiology of another organism 
  • Presence of true pheromones in humans is still debated
• Odor effects: the conscious perception of a scent that impacts our physiology 
  • Examples: the smell of a child’s head and neck can trigger innate and learned responses in a parent

Olfactory Abilities in Animals

• Animals like elk can sense odor plumes and switch between their different nostrils to geolocate 
  • They can track multiple individuals simultaneously through odor plumes
    Odor Perception in Animals
• Animals like elk can create and split multiple cones of odor attention
• They can perceive depth with their odor plumes
• Other animals do this with their odor plumes, but humans do not have this experience

Evolution of Human Perception

• Humans traded out space for greater visual acuity
• Two factors set humans apart from other animals: 
  • The duration of time in our lifespan in which we can engage neuroplasticity
  • Time perception: the ability to divorce from memories of the past and experiences in the present and also anticipate experiences in the future
• Humans can narrow or broaden their visual aperture, which affects time perception

Dreams and Liminal States

• In dreams and liminal states, humans can access visual experiences that are impossible in regular conscious perceptual states
• The brain can learn new rule sets and possibilities in these states

Mindset Effects and Belief Systems

• Aliyah Crumb’s work on mindset effects or belief effects shows that breaking rule sets in a dream state could have a similar effect on an individual as breaking them in the real world
• These effects are different from placebo effects
  Mindset Effects on Physiology
• Mindset can have significant effects on physiological responses 
  • Example: Different responses to milkshakes labeled as low calorie vs. high calorie
  • Example: Hotel workers losing weight after being informed of the health benefits of their work
  • Example: Stress responses based on beliefs about stress’s positive or negative effects
• Mindset effects can account for 8–20% of the effects of food or behavior

Creativity and Rule Sets

• Creativity involves combining existing rule sets and coming up with completely new ones
• Singular focus and purpose in life can lead to greater creativity and problem-​​solving abilities 
  • Example: Dreaming about math problems and finding solutions in dreams
• Accessing broader rule sets and coming up with new ones is more likely in states of love or unconstrained thinking 
  • Example: Raising children with an infinite number of possible adaptations for their happiness and health
• Dreaming allows for unconstrained rule sets, but they are still limited by past experiences
  Relaxation and Problem Solving
• Relaxed state allows for accessing new rule sets and solving problems more effectively
• Under stress, people struggle with novel tasks
• Creative solutions often come from a state of relaxation and desire for something, rather than avoidance

Love, Delight, and Motivation

• Major advancements in human evolution often come from a desire for something, rather than avoidance
• Delight, fascination, and curiosity can be powerful motivators for problem-​​solving and innovation
• Multiple purposes can drive people to accomplish tasks, such as love for the work and fear of negative consequences

Andrew Huberman’s Background

• Born at Stanford Hospital, grew up in Palo Alto, California
• Father was an experimental physicist, mother was a stay-​​at-​​home mom and teacher
• Exposed to the academic world and theoretical physics from a young age
• Developed a passion for biology and animals
• Parents divorced when he was 12–13, leading to a difficult period in his life
• Became involved in the skateboarding community, exposed to various elements and experiences
• Struggled with school attendance, leading to placement in a residential treatment program in 9^th grade
  Difficult Home Life and Personal Growth
• Home life was challenging due to parents’ focus on their own issues
• Lack of boundaries and rules for a 14-year-old
• Part of a community of “parentless kids”

Experience in a Youth Facility

• Felt unfair to be placed in the facility
• Counselors were helpful and supportive
• Exposure to other kids dealing with drug and alcohol issues
• Realized the importance of asking questions about personal growth and understanding

Switching High Schools and Starting Therapy

• Switched to Palo Alto High School and began therapy
• Therapy provided a supportive environment to figure things out
• Continued therapy for over 30 years, helping to understand personal thinking and separate external influences from personal desires

Personal Growth and Interests

• Stopped skateboarding due to injury and started getting involved in fitness
• Participated in martial arts, weightlifting, and running
• Improved focus on school and developed a better work ethic
  Overcoming Challenges and Personal Growth
• High school years filled with anger and lack of structure 
  • Found solace in skateboarding and physical labor
  • Started taking fire science classes while still in high school
  • Dabbled in drugs, specifically psychedelics
• High school girlfriend provided some organization and motivation 
  • Relationship faced challenges, including a pregnancy
• Attended UC Santa Barbara to be with girlfriend 
  • Struggled academically and socially, getting into fights
  • Relationship with girlfriend became strained
• Summer between freshman and sophomore year 
  • Lived in a squatting situation in Isle Vista
  • Worked at a Bagel Cafe, delivering bagels
  • Involved in a violent altercation, leading to police involvement
  • Realized the need for change and personal growth
    Bagel Cafe to Neuroscience
• Felt like a screw-​​up, wrote a letter to his mom about his past and future plans
• Took a leave of absence from UC Santa Barbara, moved home, went to Foothill College
• Focused on coursework and working out, became a straight‑A student
• Returned to Santa Barbara, lived in a studio apartment, got back together with girlfriend
• Education partially funded by his dad
• Became interested in neuroscience, worked in a lab studying brown adipose tissue, dopamine antagonists, and temperature
• Studied mental health, neurotransmitters, dopamine, and norepinephrine
• Eventually went to graduate school at UC Berkeley

Pivotal Moments and Influences

• Fight where knives came out made him realize he needed to change his life
• Connected with bodybuilder Mike Menser, who coached him and encouraged him to develop his mind
• High school football coach taught him about weight training and running
• Friend Gary Hall told him it wasn’t his fault his parents were messed up, but it would be his fault if he screwed up
• Realized discipline and self-​​imposed structure were the answer to his problems
  PhD and Postdoc Experiences
• PhD focuses on: 
  • Learning the basics of the field and being tested in the classroom
  • Learning the basics of experimentation and experimental design
  • Becoming an expert in one specific area through experiments
  • Learning the publication process, writing, taking rejection, and handling challenges in seminars
• Postdoc is similar to PhD but more focused on research and less on coursework
• Expectations for publications during PhD: 
  • Varies, but 1–2 high-​​quality papers are usually sufficient
  • The key requirement is to become an expert in one area and understand its implications in the context of the field
  • Typically correlates with having one first-​​author manuscript in a good journal

Huberman’s Journey in Science

• Moved to UC Davis to work with Barbara Chapman, a younger faculty member
• Lived in the lab, focusing solely on work and science
• Met Ben Barris, the first transgender member of the National Academy, and connected over their shared passion for science
• Initially turned down a postdoc with Ben Barris due to not wanting to be in Palo Alto, where he grew up
• Moved to Boston for a postdoc but left due to personal issues with the lab head
• Ended up joining Ben Barris’s lab at Stanford, working on retinal biology
• Eventually got a job at UC San Diego in their neuroscience program
  PhD and Postdoc Experiences
• PhD typically takes 4 years, with half in the classroom and half in the lab
• Postdoc focuses on research and developing an independent research program 
  • 80% of postdocs now go into industry
• Goal of both PhD and postdoc is to have a 1‑hour seminar of independent work and context

Working with Ben Barres

• Ben Barres was a prominent neuroscientist and mentor
• Transitioned from female to male during his career
• Encouraged questioning dogma and exploring different ideas
• Struggled with weight and experimented with various diets, including keto and fasting
• Passed away in 2017 due to pancreatic cancer

Personal Experiences and Connections

• Lived and worked in the Bay Area, overlapping with other notable figures
• Ben Barres had an interest in nutrition and supplementation, often discussing it with others
• Encountered Steve Jobs and had connections to his personal life through friends and family
  Punk Rocker Scientist
• Inspired by people like Joe Strummer and Oliver Sachs who went against the grain in their fields
• Worked on glia cells, which were initially thought to be unimportant support cells
• Showed that glia cells are important for brain functioning and development

Balancing Work and Personal Life

• Struggled with balancing work and personal life, especially in the Bay Area with high living costs
• Worked as a postdoc and wrote articles for Thrasher and Slap magazines to make ends meet
• Eventually got a job at UC San Diego and started his own lab, which flourished

Reconnecting with Father

• Went to therapy with his father to address their strained relationship
• Realized they had similar struggles and experiences growing up
• Forgiveness and understanding led to a closer relationship

Dealing with Loss and Mental Health

• Published a paper in Science and reconnected with his former professor, Harry Carlyle
• Harry committed suicide shortly after, despite his knowledge of mental health and neurochemistry
• Realized that knowledge alone might not save someone from mental health struggles

Close Relationship with PhD Advisor

• Very close with PhD advisor, Barbara Chapman
• Families were intertwined, and she had two kids while he was in the lab
• Noticed she started falling out of communication with people
  Dealing with Loss and Finding Purpose
• Speaker experienced multiple losses, including mentors and close friends 
  • Struggled with grief and feeling disconnected from work and life
  • Engaged in dangerous behavior as a coping mechanism
• In 2017, attended a week-​​long trauma immersion program 
  • Met a former Navy SEAL who challenged him to share his knowledge with the world
• In 2019, started posting short educational clips on Instagram 
  • Focused on sharing knowledge about the retina and other neuroscience topics
• In 2020, the pandemic hit and the speaker decided to focus on sharing stress management tools 
  • Appeared on 30 podcasts, including Joe Rogan’s and Lex Fridman’s
• In 2021, started the Huberman Lab podcast 
  • Aimed to honor Stanford University and showcase brilliant minds in various fields
• Continues to attend therapy and has explored the use of psychedelics for personal growth 
  • Stresses the importance of staying in touch with what gives us energy and finding purpose in life