Watching the Watchmen

By Alexandra Clemente

I was always interested in the outcasts. The dark side. The things that feel less trite. I like the things that feel cool. So, when I decided to sacrifice my youth at the monastery of encephalic knowledge, I was not going to study the mainstream — those cells of the cortex and hippocampus, the circuits involved in “higher cognition,” whatever that means.

Nah, I wanted something that sounded like a My Chemical Romance lament, not a Taylor Swift bop.

What sounds darker than inhibitory neurons? 

For those that have not sacrificed part of their brain to brain sciences, here’s essential background (and for those in the know, I apologize for my massive oversimplification; if you feel the necessity of taking my Ph.D., please inform the degree-granting institution that they have failed): neurons are the main propellers of the “electric circuits” in your encephalon. You have excitatory neurons: the ones that hype the others up. You have inhibitory neurons: the ones that keep that excitation in check. 

It feels trite to say that everything that has ever passed through your mind is electricity made by this circuit of pluses and minuses. The result of tiny things moving across a tiny fence. Ions moving across a membrane of fat. That electricity moves through liquid to move more tiny ions across a tiny membrane. And that happens ten hundred trillion million times in your lifetime. If anything goes wrong, if the balance between excitation and inhibition is off, there may be catastrophic consequences like seizures. 

Just as much as you need the hype neurons, you need inhibitory neurons to keep your electricity in check. It can’t all be positive.

The watchmen of your circuits were long neglected in research. They’re not as big and plump as the excitatory neurons of the cortex, that place of “higher cognition” that makes them more challenging to get to. These smaller inhibitory neurons vary in shape, size, and molecular makeup. They’re a parade of heterogeneous vigilantes keeping the neighborhood in your skull in order.

Studying them in the past was too complicated, so they were just cast aside.

But I wanted to study the minuses, not the pluses.

And so, like the head of police of every superhero movie, I toiled away in my windowless room during my PhD. Mapping out sightings and activity patterns of these inhibitory watchmen. Running experiments: if I do this, what do these neurons do in return? Like that head of police, I spent many nights mired in sheer frustration. Agony is perhaps the more appropriate word to use here. So many nights without a response, so many received messages that made no sense. It felt like I would never catch them, these vigilantes.

To say I lost years would also be an oversimplification. And incorrect. I was not lost. I was very contained. I had entered the monastery of encephalic knowledge and I would not leave until the inhibitory mysteries had revealed themselves to me. 

But the world spun and spun, and there were no windows in that microscope room. I was stuck in the high noon of those white lights.

You lose yourself in the tangled mess of neurons, astrocytes, and microglia — the cells of the brain. Tangled in the knots of dendrites and axons. Drowning in the molecular markers, parvalbumin and somatostatin, my lovely vigilantes express to make themselves known. Stuck in the gunk that catches in your tiny electrode. Choking because of the debilitating mouse allergy you develop.

You’re lost until you realize you are not here to control these vigilantes. You can’t catch them. That’s the wrong mentality. If you think that way, you’ll be here forever.

You’re here to observe and marvel at the capabilities of nature. To humble yourself because these inhibitory neurons know all of you; they control the electricity in your brain and everything that manifests because of it. Your fears, your loves, your desire to be known.

But you will never know all of them. And that is how it must be.

You’re here to write just one of the many heroic tales of inhibitory neurons.

The story I wrote talks about how these guardians control the gates of the cortex, that place of higher-order processing. How some of these minus neurons are connected to sensation circuits and some of them are connected to limbic, dare say “emotional”, circuits. How some of them burst, some of them don’t.  How those molecular markers that your vigilantes express map onto what they do and who they’re all.

They’re all fascinating. We need all of them, these watchmen.

My beloved minus neurons, it was my life’s greatest honor to write one of your fables. No matter where life may take me, I will always sing my ode to honor the inhibition vigilantes that keep our encephalons in check.