Over at NPJ Science of Learning, Tracey Tokuhama-Espinosa debunks the myth that “brain scans see thought.”
In brief, Tokuhama-Espinosa argues that
Each brain imaging machine can, at best, measure a single dimension (electrical, chemical, or structural) of one sub-skill set …
No imaging machine can measure thought, only a sub-element of a thought.
The whole article is worth a read. Tokuhama-Espinosa has long made wise contributions to the field of Mind, Brain, Education. Her writing always merits attention.
All those diagrams of synapses and neurotransmitters might be factually correct, but misinterpreted to explain memory formation.
Basically, some researchers argue that we’re thinking about learning in the wrong place. In the old model, we focused on many, many interactions at the very tips of the dendrites.
In a new model, the researchers propose we focus on a few changes at the root of the dendrites — much closer to the place where they connect to the neuron’s main body.
This summary explains the headlines. (The original article itself can be found here.)
Both these links include helpful visuals to understand the difference between these two models.
The details are fantastically complicated. But the possibility of a new model is…technically speaking…awesome sauce.
What Should Teachers Do With This New Knowledge?
Believe it or not, not much.
In the first place, we should remember that for teachers: neuroscience is fascinating, but psychology is helpful.
That is, we don’t really need to know exactly what changes in the brain when students learn. (Although, of course, it’s SO INTERESTING.)
But, we DO really need to know what teaching practices create those neural changes — whatever they might be.
We need to manage working memory load.
We need to help students manage their alertness levels.
And, we need to use retrieval practice.
And so forth.
In every case, psychology research tells us what teaching strategies do and don’t help. If — as might be true in this case — our neuro-biological understanding changes, that change almost certainly doesn’t matter to our teaching.
We still need to manage working memory and alertness.
We still need to use retrieval practice.
And so forth.
We might think differently about the neurons and synapses and dentrites, but we will keep using the most effective teaching practices.
In the Second Place…
Let this news remind us of Kurt Fischer’s famous saying: “when it comes to the brain, we’re all still in first grade.” That is: modern neuroscience is still a young discipline, and we’ve got LOTS more to learn.
So, we can indeed be thrilled by all the neuroscience information we glean at Learning and the Brain conferences. But, we shouldn’t latch onto it too firmly. Instead, we should expect that, as the years go by, our neuro-biological models will need several fresh revisions.
I have, in fact, waited over a year since this article was first published to see what traction it has gotten in the field. So far, I have heard almost nothing about it.
Simply put: I don’t know whether the new model is more accurate than the old. Perhaps, ten years from now, the old model will be seen as an embarrassing relic. Perhaps, instead, the new proposal will have been forgotten.
In either case, we can think more effectively about brains (and about teaching ad learning) if we keep our mental models flexible enough to allow for fresh discoveries.
In the world of science, if you see the right kind of evidence, you have to change your mind.
As of this blog post, I might start changing my mind.
Regular readers know that I frequently decry false claims about “brain training.” In particular, when people claim to increase working memory capacity, we find that those claims don’t stand up to research scrutiny. (For instance: here and here and here.)
In my last post on the topic, I more-or-less gave up on the possibility. In fact, I wrote:
So, from now on, I’m just going to assume that new claims are highly likely to be false.
If brain training claims are subsequently replicated by many research teams; if the methodologies are scrutinized and approved by several scholars in the field; well, if that happens, I’ll relent.
For now, I don’t want to be fooled again.
But maybe — just maybe — researchers might have found a strategy to improve working memory. (I can’t believe I just wrote that sentence.)
We’ve got persuasive research showing that working memory overload causes brain waves in different regions to fall out of synch.
Reinhart and Nguyen, in effect, wondered if they could help resynchronize those brain waves.
In a multi-step study, they found that:
First: asynchrony of frontotemporal theta-phase waves corresponds with working-memory declines in 60-76 year olds (compared to 20-29 year olds).
(The findings get even more technical from there, so I’ll just stick with “brain waves” for now. If you want the details, click the link above.)
Second: the right kind of external electrical stimulation resynchronizes those waves.
Third: when the theta waves resynchronized, the WM function of the older subjects returned to levels typical for the younger subjects.
Technically speaking, THAT’S HUGE. The right kind of electrical stimulation improved WM.
What Happens Next?
A) Before we get too excited, we should let some expert skeptics weigh in. Although the concept is easy enough to understand — “the right kind of brain zaps restore WM to higher capacity!” — the specifics are fantastically complicated.
We should, in other words, let other scientists in this field kick the tires good and hard.
By the way: nine researchers have responded here. Several have suggestions for other populations to study: for instance, people diagnosed with dementia. But, none of them spot glaring errors in the methodology.
(For instance: in two studies I can think of, researchers made claims about improving working memory, but tested short term memory instead. This study doesn’t include that kind of switcheroo.)
B) Again before we get too excited, we should recall: this study isn’t about raising WM capacity for students. It is about restoring WM capacity for people who have experienced a decline.
That result might benefit each of us as we age. But, it doesn’t (yet) offer benefits to our students who have typically functioning WM.
However, this technique might help younger people with diagnosed WM deficits. That finding alone could be transformative for some students in our schools.
C) We don’t really know what this might look like outside of the neuroscience lab. As professor Robert Howard warns:
The “real world” benefits of any apparent improvements in experimental working memory function associated with the technique will also need to be evaluated together with the impact of any potential adverse effects of brain stimulation.
For example, induced improvements in working memory might come at the price of worsening of other areas of cognitive function.”
D) Okay, you can now go ahead and get really excited. I have said for years that if we could improve WM capacity, that change would be like the printing press in its effect on human cognition.
For the first time in a decade, I’m starting to think that it just might happen.
If you’d like to learn more, this very helpful summary of Reinhart and Nguyen’s work is a good place to start.
My English classroom often includes discussions like these:
When we read Zora Neale Hurston’s Their Eyes Were Watching God, I might ask my students “who is the antagonist?”
To answer this question, my students must recall several bits of factual information:
the definitions of “antagonist” and “protagonist”
the major characters of the novel
their most important actions and goals
Once they’ve recalled those facts, my students have to rearrange all that information into new conceptual patterns.
Which character’s actions and goals best align with the definition of “protagonist”? (In this case, that’s an easy question. Janie Crawford is far and away the likeliest nominee. )
Who’s the antagonist? That is, which character’s actions and goals thwart Janie’s?
That’s a much harder question, and students must wrestle with several possibilities as they develop a plausible argument.
Let’s Talk About the Mind
Where do my students hold and process all this information?
For a psychologist, that’s an easy question: working memory.
Working memory allows students to select, hold, reorganize, and combine information held in long-term memory: in this case, the novel’s events.
It also allows them to select, hold, reorganize, and combine information perceived from the environment: the question I just asked about antagonists.
Because we constantly ask our students to hold and combine bits of information, our students use working memory all the time.
When we ask students to calculate the volume of a solid, or to compare historical figures, or to explain a trophic cascade, or to predict what will happen when I roll a ball down a ramp, we’re asking them to use working memory.
By the way: this truth hold for skills and processes as well. Why is learning to drive a stick shift so hard? Because you must hold, combine, and co-ordinate several distinct physical processes.
And, here’s an essential point: we don’t have lots of working memory to use.
Let’s Talk About the Brain
We know a lot about the mental processes involved in working memory. (I might have written a book about them.)
But, the neuroscience of working memory has been harder to study.
In the world of psychology, we know that WM can be easily overwhelmed.
But, in the world of neuroscience, we don’t know exactly what happens at that moment.
In other words: what’s happening in the physical object of the brain that accounts for the mental difficulty?
What happens, for example, when I can’t shift gears properly on this stupid manual car?
Are neurons somehow disconnecting from one another? Are electrical signals going haywire? Perhaps neurotransmitters are watching kitten videos on Youtube ?
Today’s News
We’re starting to get an answer to that question.
New research suggests that successful working memory functioning requires that distinct brain regions operate synchronously.
When they reach overload, those regions fall out of synch.
Once those regions no longer synchronize, then students might struggle to solve math problems, or sound out a word with new phonics rules, or conjugate a verb in a freshly learned tense.
Like much neuroscience research, this study is fantastically complicated. Luckily, it’s been described quite well by Jordana Cepelewicz over at Quanta Magazine. (No need to worry about the “seven plus or minus two” formula.)
The good news here is clear: we’re starting to get a clearer picture about the neuroscience of working memory overload. Because teachers should be obsessed with working memory overload, we might well be intrigued by this news.
We should keep in mind, by the way, that this research so far has been done with monkeys. Whenever considering new research, always keep this rule in mind:
Never, never, never change your teaching practice based on research into non-human animals.
At some point, we might get neuroscience research that helps teachers manage working memory load. Although that day isn’t today, we should be glad that research possibility is clearer now than before.
At a professional development talk on long-term memory formation, a teacher politely scolded me: I should have spent more time discussing alpha waves and gamma waves.
After all, she said, that was the really important stuff when it came to brains and learning.
Of course, the differences between alpha and gamma waves can fascinate us. And, pictures of various graphs can look dramatic — especially if the graphic designer has made the colors particularly attractive.
And yet, this kind of neuroscience information offers almost no useful guidance to teachers.
Here’s why.
What Should Teachers Do?
Pretend for the moment that we can plausibly say “this brain region shows gamma waves when it is learning, and alpha waves when it isn’t.”
(By the way, we almost never can say that plausibly. But, we’re pretending here.)
What should teachers do with that information?
Presumably we should ask: how can we reduce alpha waves and enhance gamma waves?
The answer to that question will always include a particular teaching practice. We should use retrieval practice. Or, we should space out repetitions. Or, we should reduce working memory load.
In every case, we know about the effectiveness of those teaching techniques by studying psychology, not neuroscience.
We can, of course, see changes in brain activity when use various classroom techniques.
But, we can determine their effectiveness only by measuring some behavioral outcome. Did the students do better on the test? Did they pay more attention to the stimulus? Or, did they demonstrate higher working memory scores? In every case, those are psychology questions.
Today’s News
I write about this topic every few months, because confusion between the two disciplines crops up fairly regularly.
Some of their resources explore the topic in a general way. The final link leads to a hot topic indeed: Daniel Willingham and Daniel Ansari challenge Jo Boaler and Tanya Lamar’s interpretation of neuroscientific data.
If you’ve been following debates about prior knowledge and math teaching, grab some popcorn and surf on over to that link.
In the second, he’s got a lively writing voice. Better than most, he can explain important brain concepts without being pedantic, and without relying on Latinate jargon.
The website covers several helpful topics: the importance of sleep, the structure of synapses, the reasons brains have two hemispheres. (And: why being “left-brained” really isn’t a thing.)
I recommend this website as a lively introduction to (or review of) important neuroscience information.
And: if you want to know the answer to that spider/Hungary question, click here.
Science relies on skepticism, so let’s ask a skeptical question:
“Does it really benefit teachers to understand brain research? Isn’t good teaching good teaching?”
If you’re reading this blog, you doubtless already see the value that brain research offers teachers.
The more we know about — say — motivation, or “the spacing effect,” or the benefits of interleaving, or the perils of “catastrophic failure,” the better our work can be.
But, I think there’s more.
The more time I spend in this field, the more I see benefits for school communities and even international collaboration.
Uniting Schools with Common Language
I once spent the day working at a K-12 school in Texas. At the lunch break, a teacher approached me and said:
“I’m so impressed you know all our names! I’ve worked here for years, and I don’t know the names of the high-school teachers. After all, I teach in the lower school.”
This confession speaks a larger truth: we can all-too-easily fall in the habit of talking only with our nearest peers.
3rd grade teachers confer with other 3rd grade teachers. High-school English teachers huddle up with high-school English teachers. (I should know; I’m a high-school English teacher.)
This habit makes some sense. I don’t really know how my lesson-plan for Their Eyes Were Watching God would translate to, say, a first grade classroom. What teaching topics might cross so wide a curricular gulf?
The answer: brain research.
A strategy I use to manage working memory overload for 10th graders might transfer quite easily to a 3rd grade classroom. At a minimum, the benefits of that strategy will be immediately clear to anyone who understands the importance of working memory.
When all teachers in a school know the languages of neuroscience and psychology, we can talk about our work more deeply, meaningfully, and effectively with colleagues in other grades and other disciplines.
Uniting Countries with Common Language
I spent the last two weeks in Japan, working with Fukuoka International School and the American School in Japan. In Fukuoka, I worked with teachers from about a dozen countries: the US, Canada, and Japan — and also China, Korea, Vietnam, Thailand, the Philippines, Australia … even Myanmar.
As you can imagine, these countries have dramatically different educational systems, philosophies, cultural expectations, and curricula. What shared language might these teachers find?
Here again, these teachers were amazed to see how quickly they could share teaching strategies — once they could describe them in this new way.
A game for retrieval practice, for instance, might be used with different topics in different countries. Heck, it might take place in various languages with incompatible alphabets.
But the core psychological practice remains the same, no matter the curricular or linguistic translations.
In two sentences…
I joined the Mind, Brain, & Education movement because I thought it would help make me a better teacher. Every day I see more clearly: it can make all of us — schools, districts, even international communities — a better education system.
The more teachers learn about neuroscience and psychology, the more we admire Dr. Mary Helen Immordino-Yang.
Unlike most researchers, she has spent time as a classroom teacher.
And, her extensive research—in both neuroscience and psychology—offers us wise perspectives on our craft.
For instance, she has zealously emphasized the inextricable connection between emotion and cognition—although we live in a society that wants to keep the two apart. As she has shown in her books and articles, we can’t think deeply about thinking without understanding the importance of feelings.
Thinking and feeling aren’t two different things. They’re names for distinct perspectives on the same thing.
(You can check out her essay in Mind, Brain, & Education: Neuroscience Implications for the Classroom, edited by David Sousa.)
More recently, working with Linda Darling-Hammond and Christina Krone, Dr. Immordino-Yang has published a lucid and practical summary of our field. In 20 jargon-free pages, she makes a strong case for focusing on development as an essential variable in schools and in learning.
You can download The Brain Basis for Integrated Social, Emotional, and Academic Development here.
That’s a mouthful of a title. But it synthesizes an impressive range of complex and vital topics: age-appropriate teaching strategies, neural development across the lifespan, epigenetics, even cultural well-being.
As an introduction to The Brain Basis, I interviewed Dr. Immordino-Yang. This transcript is edited for clarity and brevity.
Andrew:
You’ve packed a lot of information into this document. What’s your goal in putting it all together this way?
Mary Helen:
I wanted to tell a story about what it means to be a human being.
From there I thought we could think back to retrofit what are we doing in schools to support the development of our full humanity.
And so I aimed to tell a story of many fields—of biological, genetic, developmental, and cognitive research that would help people understand why human development and learning are so closely tied together.
Schools really can no longer ignore the new evidence about human development in thinking about our aims and our strategies in educational environments.
Andrew:
A big chunk of this brief talks about different developmental stages, and the appropriate educational strategies to use during each one.
Where you get the most pushback? What are people most surprised about?
Mary Helen:
One of the things that people have been very surprised about, and where I get a lot of pushback, is in adolescence. I talk about adolescence being a fundamental time of plasticity—but also of vulnerability.
And this means that teenagers really need deeply supported opportunities to explore alternate identities: scholarly ways of thinking and being, social ways of thinking and being.
This is a time when kids can develop very deep interests, and connect those interests to their world—how it is now, how it has been in the past, and how it could be different in the future– like they never have been able to do before to the same extent.
Schooling needs to capitalize on that. Yet we really do not in the way that standard schools are designed. In fact we directly undermine that kind of agency, that kind of exploration of self and ideas that’s just fundamental to adolescence.
Andrew:
In schools, I’m guessing that would mean more electives, fewer requirements. You’d like more open-ended, freeform opportunities for high school students?
Mary Helen:
Well, yes. But all that in the context of very strategic support and close relationships, in addition to intellectual and social opportunities to really get invested in important work: more like an apprenticeship model of schooling in adolescence, as compared to a didactic transfer model.
There are schools doing this extremely well. They tend to be schools built for kids one step away from failing out of society, though.
For example: The New York Performance Consortium Schools got special dispensations to not have standardized testing. Instead they do performance-based portfolio work as a graduation requirement.
These students were mostly at risk of failing [in their prior schools]. And then lo and behold, when you redesign their educational experience so it’s more of this apprenticeship model—students focus on broad, relevant problems—they begin to think in scholarly ways. They develop deep understanding and explore innovative solutions.
These kids go on to college at far higher rates. They’re graduating college. They’re just ever so much more engaged than their peers.
We’ve got this misunderstanding that when kids are doing poorly and flailing around, you want to double down on discipline. You want to straighten them out and get them on the straight and narrow. Control them first, and then you can teach them.
In fact what you need to do is offer them opportunities to really utilize the energy that they have, and to question and rethink their ideals, to build their deep desire for inventing themselves. And give them a creative, scholarly, structured outlet in which to productively explore that.
Andrew:
And, as you say, that makes a lot of developmental sense.
Let’s change gears. This document talks about three essential brain networks: the Executive Control Network, the Default Mode, and the Salience Network.
This is essentially a neuroscientific way of thinking about learning.
Another approach is the psychological approach: let’s think about motivation, let’s think about attention, let’s think about working memory.
When you talk with teachers about this neuroscientific approach, does it deepen their understanding of the psychological framework? Does it conflict with it? Does it confuse it?
Mary Helen:
I think it really does [deepen their understanding]. I hope it does. My aim was to teach educators about the dominant models of brain development right now.
There are hundreds and hundreds of studies demonstrating how these networks work. And those networks had really not been explained to educators to this point.
What you notice about them is: none of them is emotional or cognitive. These networks are both [emotional and cognitive] all the time. No one of them is the social network. They all have a role to play in sociality.
Andrew:
In the past you’ve written that there’s relatively little neuroscience that teachers need to know. So this approach is quite a change for you.
Mary Helen:
Well, not really. What I really think people do need to know is about human development. And one of the sources of evidence is neural development.
Understanding the basic functionality of the [neural] system is important for supporting the development of the person.
And don’t get me wrong: in some of the best schools in the world the teachers don’t know diddly squat about brain development.
But they really, really understand what their aim is for their students. They know in a deep way about the kinds of thinking and relating and reflection that they want their students to be capable of.
And in that case you don’t need the neuroscience anymore.
I think we need it in the United States because we have such a faulty model of how learners learn, and what to do when they’re not doing as well as we would like.
I’ve written several papers about the default mode network for example. We in education are potentially undermining the development of deep thinking, deep understanding, deep integration of content because of our overly task-oriented focus.
We shift people into an outwardly directed task-oriented state too much at the expense of reflection and synthesis that happens internally in a narrative constructive process.
Andrew:
So much of our vision of good teaching is a kind of a performance. It’s external, it’s what the students are doing.
Mary Helen:
That’s right. It’s about what you do, it’s not about how you think. And good thinking takes time. It takes skills for reflecting. Those skills are often neglected in our schools.
We have this kind of “frantic productivity model” which is basically a lie about what meaningful accomplishments students are actually accomplishing.
Andrew:
The “frantic productivity model” sounds a lot like schools where I’ve worked.
American education has been battling between constructivism—“inquiry-based” and “project-based learning”—on the one hand, and direct instruction on the other.
Your brief is calling for a truce. You say that these approaches can work well together, and we’re looking for a wise balance.
My question is: as a teacher how do I know when I’ve gotten that balance right? What does that feel like? What does it look like?
Mary Helen:
Yeah, great question.
So here’s the thing: this is where the teaching skill comes in.
And what skill do you need to have? What teaching artistry do you need to have? You need to deeply understand your students, and deeply understand your aim for them.
What’s your intent in the lesson?
Too much of what we do in education is designed around an outcome—a “learning outcome.”
Instead, it should be designed around this question: what are the kinds of mental capacities and habits of minds that students will be practicing?
To balance constructivism with direct instruction, think about the how much more than the endpoint. And then the answer will look really different in different contexts: different kids, different content, different supports and scaffolds, at different times.
At this point, our conversation turned to a description of a specific school focusing exactly on these complex questions and difficult choices.
That discussion was so interesting that it deserves its own blog post. I’ll have that live for you within the month.
If you give shoppers many jam choices to sample, they’re delighted to taste your wares. But, if you give them fewer choices, they’re more likely to — ahem — buy some jam.
In other words: choices both motivate and demotive in a complex pattern.
What effect might this finding have on education?
Choices Overwhelm Brains? Choices Harm Learning?
In a recent study, Elena Reutskaja and colleagues explored the neural basis of this intriguing finding.
They gave study participants choices about the image to be printed on a tee-shirt or mug. Crucially, some got a few choices: 6. Others got more choices: 12. And others got A LOT more: 24.
What happened in participants’ brains?
The short version: two crucial brain regions behaved differently with 12 choices.
The anterior cingulate cortex (ACC) and the striatum showed more activity when given a manageable number of choices than when they had too many or too few.
By the way: the prefrontal cortex showed a similar pattern, but to a smaller degree.
(Important wonky caveat: more brain activity ISN’T always better. In this case, more activity in these regions coincided with self-reports of greater pleasure.
In other cases — say, dyslexia — more brain activity coincides with lots of reading difficulty.)
These results mean that we’ve got two reasons to think too many choices are bad.
First: behaviorally, people react badly with too many choices. (If you try to navigate the toothpaste section of your local CVS, you know what I mean.)
Second: neurobiologically, brains react badly with too many choices.
In other words, those people running the behavior experiments weren’t making things up or misreading the data. Instead, they identified real problems.
Teaching Implications
We might reasonably start with the presumption that choices enhance learning. The more that our students get to choose what they’re doing, the more intrinsically motivated they will be.
However, as we see more and more studies like this one we realize that — just possibly — choices harm learning. Faced with more options than they can readily process, students feel their ACC shut down.
The result: not more learning and motivation, but less.
What, then, is the perfect number of choices?
One answer is: the authors suggest between 8 and 15.
A much better answer: honestly, research really can’t answer that question.
In the first place, they’re currently doing research with consumers getting choices to buy stuff. That’s not the situation our students are in.
In the second place, this research pool works with adults. Almost certainly, younger students can manage fewer choices than older students — who manage fewer than adults.
In the third place, the “choices” that students make vary in complexity. If I have to define 5 of 6 vocabulary words, that’s a straightforward process.
If, however, I have to solve 5 of 6 calculus problems, then I’m likely to start the early steps of solving each one to test out their trickiness.
In this case, I’ve got A LOT more info rattling around in working memory, even thought the number of choices has remained the same.
In other words, the correct number varies from case to case to case. As is so often true, you — the classroom teacher — will have the best vantage point from which to suss out the answer.
If you’ve seen the documentary Free Solo, you know about Alex Honnold’s extraordinary attempt to climb a 3000 foot sheer rock face.
Without ropes. Without protective gear of any kind.
And without, it seems, a typically functioning amygdala.
https://www.youtube.com/watch?v=nF-7H5Dk26E
Free Solo briefly mentions Honnold’s visit to Jane Joseph’s lab. (You see a quick image in this trailer.)
At the time, Joseph studied high sensations seekers: people who are “drawn to intense experiences and are willing to take risks to have them.” That is, for example, people who habitually scale sheer walls of granite.
(Descriptions of Honnold’s visit appear in J. B. MacKinnon’s excellent essay: “The Strange Brain of the World’s Greatest Solo Climber.”)
The Case of the Quiet Amygdala
Using fMRI scanning, Joseph’s team examined Honnold’s brain. In particular, they focused on the reactivity of his amygdalae.
These small, almond-shaped regions of the brain sit at the tip of the hippocampus. Their function, simply put: to process strong negative emotions, like fear.
(For scrupulous readers, “amygdala” is singular; “amygdalae” is plural.)
Jane Joseph — like many others — wanted to know: did Honnold’s amygdalae react differently than those of others?
To test the question, she showed him 200 pictures, many of them gruesome or disgusting: “corpses with their facial features bloodily reorganized; a toilet choked with feces.”
Neurotypical observers — like the control subject Joseph also scanned — show strong reactions to these images.
Honnold’s amygdalae? Nothing. Nada. Bupkis.
Explaining the Inexplicable
MacKinnon describes Honnold’s free climbing this way:
“On the hardest parts of some climbing routes, his fingers will have no more contact with the rock than most people have with the touchscreens of their phones, while his toes press down on edges as thin as sticks of gum.”
Honnold’s quiet amygdalae might explain his fearlessness. But, what explains his quiet amygdalae? How can you stand 2000 feet about the ground on a stick of gum without gut-tormenting terror?
(If you’re like me, your palms start sweating when you see him standing there. Now, imaging being there…)
To be clear, we should note that Honnold does have amygdalae. The MRI scan shows them, looking perfectly normal.
(Very rarely, some people have deformed or absent amygdalae. They don’t typically grow up to be free soloists, but they do demonstrate much less fear than others.)
Two explanations might help us understand Honnold’s remarkable brain. [Edit: to be clear, both these explanations appear in MacKinnon’s article.]
In the first place, genetic variability creates a range for all human functions and characteristics. For example, men average a height of just under 5’10”. The tallest man, however, towers at 8’2″.
In this case, Honnold might have — by the luck of the genetic draw — extremely under-reactive amygdalae.
Beyond Genes
In the second place, he might also have developed techniques for re-evaluating scary/terrifying situations. By mentally “reviewing the tapes” of his climbs, by deliberately re-evaluating them calmly and rationally, he can desensitize himself to the fear that would grip practically anyone else.
In other words: a combination of nature (genetics) and nurture (deliberate re-evaluation) might tame Honnold’s amygdalae, and allow him to face extra-ordinary terrors with extra-ordinary calm.
In just the right conditions, our brains can help our bodies do almost anything. Like: scaling a cliff with preternatural sang-froid.
To hear Honnold talk about his experience of fear, click here.
For other strategies to calm the amygdala, click here.
To learn A LOT more about emotions and fear, read Joseph LeDoux’s The Emotional Brain: The Mysterious Underpinnings of Emotional Life. Also, Behave by Robert Sapolsky.
Edited to credit MacKinnon’s article explicitly for the two explanations of Honnold’s unusual neural inactivity.
