temperature rises. Your gut begins to tighten. In small doses like this,
the adrenaline rush is fun. You feel present; the B roll of your mind
falls away, and there’s a heady release of endorphins when you’re
safely through. Kayakers sometimes call paddling big water “combat
boating,” and when hard-shell boaters roll their overturned kayaks
back upright while still strapped in, it’s called a combat roll.
I saw the basic inanity of this metaphor while surrounded by these
very real veterans. In war combat, the stress response isn’t small or
ephemeral. It’s big. And it lasts for days, sometimes weeks or
months. It lasts so long that the brain changes—more in some people
than in others. Blame evolution. Our nervous systems are naturally
hardwired for fear, telling us what to avoid and how to stay safe.
Some psychologists argue that fear is our oldest emotion, existing in
the earliest planetary life forms and predating even the drive to
reproduce. It starts deep in our brainstem, in the Milk Dud–sized
amygdala.
When fear alone rules us, we lack the smarts to do much of
anything creative, or interpersonal, or spatially demanding. Part of
what makes us human is that our brains evolved a neocortex, the place
where we plan and puzzle and tell ourselves we’re being drama
queens. A fright causes a neurological tug of war between the old and
new brains. In the deep clutch of fear, our primitive brainstem
overrides our problem-solving neocortex, and we become stupid.
With PTSD, the brain stays locked into amygdala hyperdrive. Failing
to bounce back to baseline, it loses the ability to distinguish between
a real and a perceived threat. That’s why soldiers with PTSD often
cannot tolerate driving or shopping or loud noises even in safe places
when they return home.
But there’s a reason we feel fear. It may have given us the gift of
memory. The very reason we remember anything may be that we
must remember near-misses, narrowly avoided dangers, and attacks
from predators and enemies. Thanks to fear, we enjoy the smell of