There must be something wrong with Alex Honnold’s amygdala.

The free solo climber who, last week, made history by climbing Taipei 101 without ropes or protective gear, and who, in the same death-defying fashion, previously climbed Yosemite’s El Capitan, has shown no fear whatsoever.

My palms were sweaty and heart rate elevated the entire time just simply watching him achieve the feat live on Netflix. Based on countless accounts the day after, the six million other live viewers apparently also felt the same.

Yet, there he was, climbing each section of the 1,667-feet tower, calmly, methodically, and, most of all, joyfully. If there was any doubt, hesitation or fear, it simply never showed. The level of strength, skill, and precision he displayed prompted commenters to declare him the greatest athlete, not just of the sport, but in the world. 

No one can argue with this. He is the only athlete who can claim he has not once made a mistake. Because when one makes a mistake while free-soloing, the consequence is death. That is the very essence of this mad sport Honnold has chosen.

He has climbed what ordinary mortals would consider unclimbable — like sheer granite rock faces where he balances on edges as thin as a stick of gum. At times, he carries and deftly maneuvers his body with just his fingertips. The sport requires not just superhuman grip strength, his entire body has to be strong as well.  And this includes his brain.

And what a brain Honnold has.

In 2016, Honnold agreed to undergo an MRI study led by cognitive scientist Jane Joseph, who focused on his amygdala — the small, almond-shaped structure long associated with fear processing. Sensory information flows through the amygdala before being translated into emotional responses. When danger is detected, this region helps generate the feeling we recognize as fear.

There exists a rare condition, Urbach–Wiethe disease, that damages the amygdala and leaves sufferers unable to feel fear. Honnold does not have it. His amygdala is anatomically intact.

Yet when researchers showed him deeply disturbing images — the kind that reliably make people flinch, recoil, or avert their eyes — his amygdala registered virtually no activity.

Next, the scientist tried to activate the rewards circuitry in his brain by telling him he could win nor lose a certain amount of money depending on how quickly he clicked a button when signaled. Honnold’s nucleus accumbens, located not far from the amygdala near the top of the brainstem, showed zero activation, again.

The hardware is there. The wiring is not broken. But the system runs differently.

Honnold is, quite simply, fearless.

But this wasn’t always the case.  Honnold vividly remembers his first major ropeless rock climb 20 years ago at what is called Corrugation Corner near Lake Tahoe, California, classified as a 5.7 in the one to 10 scale of difficulty. He clung for dear life on the holds.  

“I overgripped the shit out of it,” he said in an earlier interview with Nautilus.  

But Honnold didn’t let the terror he felt during that first climb to deter him from doing more. He said he learned to don his “mental armor”  and has since crossed the threshhold of fear again and again and again. 

It was as if the repetitive process chipped away at his mind’s ability to absorb fear. His frontal cortex has become so powerful that calm overcomes trepidation every single time.

Research has recently shown that whenever we recall a memory, it undergoes reconsolidation, that is, we are able to add new information or a different interpretation to our remembrance.  In other words, we have the capacity to actually turn fearful memories into fearless ones.

Reading about this made a lot of sense to me.  I’ve confronted two of my greatest fears — of heights and drowning — by doing activities that repeatedly expose me to it.  Every time I climb a mountain or join a trail race, I face my fear of falling, head on.  To address my fear of the water, I took swimming lessons and plunged into scuba diving, eventually securing an advanced open water certification.  

Because of these conscious efforts, my fears have somewhat lost their authority and I am able to explore and enjoy more of the life that I would have otherwise missed. Honnold knows this only too well: To conquer fear is to be fully alive.