Dr. Andrew Huberman, Ph.D. is a Professor of Neurobiology and Ophthalmology at Stanford University School of Medicine. His lab focuses on neural regeneration, neuroplasticity, and brain states such as stress, focus, fear, and optimal performance.
In this episode of Huberman Lab, Dr. Huberman takes a deep dive into the science of pain, the mechanism by which it arises in the body and brain, and how we can control our experience of pain. Dr. Huberman also discusses phantom limb pain, traumatic brain injury, and acupuncture.
Host: Andrew Huberman (@hubermanlab)
Neuroplasticity allows our nervous system to change itself in response to experience
Somatosensory system: system involved in understanding touch and physical feeling on the body
Sensors that reside in skin and deeper layers respond to mechanical touch, heat, cold, vibration, etc.
Receptors send information via axons down spinal cord and to the brain
Pain has a physical and mental component
Pain has a perceptual component – “pain is a belief system about what you’re experiencing in your body.” – Dr. Andrew Huberman
Nociception: physiological term which describes the mechanism without the emotional component 
Understanding pain offers systems we can leverage to understand the difference between pain and injury 
There can tissue damage (e.g. radiation, x-rays) without physical sensation of pain
There can be pain without tissue damage – visual image of something we perceive as painful can give feeling of pain
Pain has some genetic component and some adaptive role
Plasticity of perception has significant impact on emotion pain and trauma
The pain system is subject to perceptual influences
Our interpretation of an event is powerful dictating our experience of the event
Adrenaline blunts experience of pain
People who anticipate an injection of morphine report reduced pain because they know the relief is coming
Feeling of love, infatuation, obsession – internally blunts pain response possibly because of dopamine release
Looking at an image of a loved one allows people to reduce pain response and raises threshold for pain  
Homunculus is a representation of the body surface which is scaled in a way that matches the sensitivity
Homunculus shows the size of brain area as related to density of receptors, not physical area
Areas of the body with more dense receptors will be more sensitive to pain than others
More receptors = more blood vessels and glia that respond to inflammation
Phantom limb pain: sensation of removed/amputated limb in the position it was at the time of trauma
Representation of hand is intact in the cortex and it’s trying to make sense of proprioceptive feedback
Potential treatment: use the mind to control the perception of what’s happening in the body
Mirror box visualization exercise: place intact limb in a box with mirrors and visualize opposite (removed) limb to remap brain’s image of body surface
Patients who performed mirror box visualization reported immediate relief of pain
Atrophy happens because nerves sending signals to muscles are inactive so muscles don’t contract
If there’s damage to sensory-motor pathways or limb, there’s a benefit to restricting the use of an uninjured limb
Restrict movement of intact, uninjured limb to force some movement in injured limb and increase plasticity in the brain
Imbalances between the right and left body quickly become exaggerated if use is restricted
Senses and movement are competing for space in the brain so we need to respect the competition
Encourage activity of injured limb, as much as possible without pain or further injury
Recovery is faster in patients who restrict the use of uninjured limb and safe use of an injured limb
Examples: in a shoulder injury perform some reaches, with a knee injury gently ride a stationary bike to equally work both sides
TBI can cause general degradation of brain function
Symptoms of TBI: headache, photophobia, mood changes, sleep disruption
The brain has a heightened capacity for repairing itself earlier in life versus later
Try to avoid a second TBI if you have had one
The glymphatic system in the brain clears out debris that surrounds injured neurons
Most activity of glymphatic system happens during the earlier part of the night during slow wave sleep
Two methods of glymphatic system activation: (1) sleeping on the side instead of back or stomach; (2) sleep with feet slightly elevated
Exercise for improved glymphatic system function: zone 2 cardio (low-level cardio) like a light jog, walk, an easy bike ride – 30-45 minutes 3x per week
Acupuncture uses needles to stimulate electricity in the body
Acupuncture illuminates cross-talk between the somatosensory system and autonomic nervous system
Acupuncture can modulate pain and inflammation but there has to be a systematic understanding of the effect you are trying to achieve
Certain patterns of intense stimulation of the abdomen can liberate immune cells and counter infection
Stimulation of feet and hands at low intensity can reduce inflammation
There are real maps of our body surface that interact with our molecules and stimulate or reduce inflammation, blunt response to pain, increase (good) inflammation
Not all inflammation is bad: inflammation is a tissue repair response – it calls cells to the site of injury to treat
Inflammation has a negative connotation because unchecked or chronic inflammation is bad
Wim Hof breathing and ice baths release adrenaline and can counter infection but you want to dose and regulate the release
Adrenaline and inflammation is adaptive at the moment
Short term plasticity can make us better able to cope with an acute event
Sleep is essential – 8 hours of sleep or at least 8 hours immobile
Walk 10-min per day unless it exacerbates the injury
Ice numbs the environment of injury and has a placebo effect but also has negative effects that may offset the use
Ice can restrict movement out of the injury site
Heat can improve the viscosity of tissues and improve blood and damage out of the area
Sunlight may be as effective as red light
PRP has never been shown to have an effect itself
The number of stem cells in PRP is minimal
Stem cell technology is on the horizon but needs much more research
The concern is stem cells can become a number of things so it’s difficult to know the safety for a specified area
Blood from umbilical cords has been shown to vitalize brain tissue in mice
It’s possible that young blood may be used to treat neurological pathologies in the future