How to Learn Faster by Using Failures, Movement & Balance

The episode opens by defining its subject. The host introduces himself as a professor of neurobiology and ophthalmology at Stanford School of Medicine and says the topic is how to change the nervous system for the better. The nervous system is described as more than the brain and spinal cord. It also includes the connections those structures make with the body's organs, and the connections the organs make back. The host calls it responsible for "everything we know, all our behavior, all our emotions," and places it at the center of how we experience life.

The central idea is that humans, unlike other species, can change their nervous systems through specific, deliberate actions. Movement and balance are presented as "windows or portals" into that change, even when the change we want has nothing to do with learning a new movement or improving balance. The stated goals are broad: feeling differently about past, present and future experiences, and learning faster. The host promises to explain mechanisms and scientific data so listeners can fit their learning practices to their own goals, rather than relying on tricks.

We're not going to discuss hacks, a word I loathe. We're not going to discuss gimmicks.

To answer whether the brain controls behavior, the host first equates behavior with movement. He then describes two groups of neurons that matter for neuroplasticity. Lower motor neurons sit in the spinal cord, in the ventral horn for those who want the anatomy. They send axons out into the body, where they connect with muscle and trigger it to twitch and contract.

There's no such thing as muscle memory. Muscles are dumb. They don't know anything.

The point is that motor patterns are stored in the neurons that control muscles and in their firing patterns, not in the muscles. In the host's words, the ability to walk "is not muscle memory, it's neural memory." Lower motor neurons "do what they are told." One of their sources of instruction is the central pattern generators (CPGs) in the brain stem, which produce repetitive movements. Breathing is the example given. The pre-Bötzinger neurons, attributed to Jack Feldman and colleagues at UCLA, send signals down the phrenic nerve to the diaphragm and run inhalation and exhalation without conscious effort. Breathing can still be changed deliberately. Walking's right-left alternation, learned in childhood, is another CPG-driven pattern. CPGs are described as "the marching orders from the brain stem to the lower motor neurons."

Upper motor neurons sit in the motor cortex and send the specific signals behind deliberate action, such as making a morning cup of coffee. Once an action like that becomes nearly reflexive, much of the information for performing it has moved to circuitry "more or less in the brain stem and below the motor cortex." The host explains why this anatomy matters. To change motor patterns, you need to know where in the circuitry change is possible, where it is most likely, and how to tell the nervous system that change is needed. He calls this overview the equivalent of an introductory college lecture on motor control and says the real subject is plasticity.

The host rejects the idea that running, biking or simply repeating motor patterns will open plasticity. He says exercise is "wonderful and healthy." It can improve cardiovascular function and help maintain strength and bone density. But he argues that working out maintains the nervous system rather than changing it. Plasticity requires "certain things," which he promises to spell out.

He reframes the question as whether behavior can change the brain. His answer is a conditional yes, and he repeats the condition for emphasis. He then adds the word "well," since nobody can perform a behavior they don't yet know. He says this condition is largely missing from public discussion of neuroplasticity.

Can behavior change the brain? And the answer is yes, provided that behavior is different enough from behaviors that you already know how to perform.

The host is skeptical of popular learning techniques such as name-memorization schemes, first-letter arrangements and mnemonics, which he calls "really gimmicky." He says the literature generally shows that people with extreme memory are "pretty poor at other things." He also describes people who over-remember and "suffer tremendously," recalling things like the number on a bodega receipt from a Coca-Cola purchase 10 years earlier. He offers these as general characterizations and does not name specific studies here. His conclusion is that the goal is to be selective about brain changes.

He separates adaptive changes from what happens after traumatic brain injury, dementia or neuron loss, and defers those topics to a future episode. The focus here is on behaviors that open up plasticity so it can be applied to whatever someone wants to learn or unlearn. His examples include learning to dance, getting better at languages, and removing "the emotional load from a particular memory of an experience." He describes the approach as "using behavior as a gate to enter states of mind and body that allow you to access plasticity."

The first kind of adaptive plasticity described is representational plasticity: changes in the internal representation of the outside world. The host says we have a map of auditory space, with different neurons responding to sounds on the right and on the left. He demonstrates by snapping on each side and jokes that his left-hand snap is weaker. We also have a map of visual space and a map of motor space. Proprioceptive feedback tells us where our limbs are even when we can't see them. He notes that people who lack certain proprioceptive neurons control their movements poorly and get injured often, calling it "a terrible situation."

These sensory and motor maps are merged. Reaching for a pen, we produce about the right amount of force and rarely overshoot or miss. This alignment sets up the main mechanistic claim of the episode.

The way to create plasticity is to create mismatches or errors in how we perform things.