Executive Function as a Scarce Resource
Meditations on limitations
Decisions have to be made.
That is, in the end, the essence of what a decision is - among multiple options, a single path must be chosen, and someone has to be the one to do so.
We call the capacity to make decisions executive function.
It’s what you exercise when you make choices, when you move through the world as a person rather than an NPC, when you actively guide the future to an outcome you desire (as opposed to being swept along by the tides of life). When you take arms against a sea of troubles and, by opposing, end them - that’s executive function.
And the thing is, executive function isn’t infinite. No one has an unlimited capacity to do this. Making choices wears you down; there’s literally something called decision fatigue that you can get after being forced to make too many, where your brain refuses to make any more decisions because whatever fuels that ability is used up.
A lot of human behavior can be understood by realizing that executive function is a scarce resource. And you can improve your life by better allocating your existing capacity for executive function.
You’re tired. You’ve just gotten off work, and you spent all day answering emails and making decisions, organizing efforts and planning ahead.
You’ve been using up mental resources (and possibly physical ones as well). It’s tempting to think of this resource as willpower, the capacity to make yourself do what things you don’t directly want to do, but that isn’t quite it.
I do think that willpower, or something like it, is real - see spoon theory. There’s definitely a point at which you can’t make yourself do things.
But this sensation isn’t quite that. After all, you can still make yourself drive home. If there was an emergency and you had to take someone to the hospital, you’d do it, exhaustion be damned.
Instead, what you’ve run out of is the ability to choose among multiple options. To steer yourself and/or others through a decision tree. You’ve run out of executive function, and so what happens when you get home is what always happens when you get home - whatever the default habit is, because that’s what requires the least amount of choice.
If you’ve got good habits maybe you work out or cook dinner. If you’ve got bad habits maybe you’re plopping onto the couch with a six pack and turning on the boob tube. The difference between those two scenarios isn’t what you choose to do, because the whole point is that you’ve run out of the ability to make choices. You’re not choosing to be healthy or choosing to be lazy; you’re not choosing at all.
And the thing that happens when you don’t make a choice is what we call ‘habit’.
There’s a trope in fiction - and plausibly real life - of the high-powered executive who hires a dominatrix.
Why?
Why would someone with money and power want to submit and be told what to do?
Why would anyone?
Why is it easier to follow than to lead?
Because following doesn’t cost executive function, and leading does.
People submit, follow, kneel, and obey because it’s easier, because executive function is a scarce resource.
Compellingly, not spending that resource is usually very relaxing. People find it a relief to not have to make decisions, to not be in control.
Hence a high-powered executive hiring a dominatrix.
Tiktok is heavily optimized for engagement. People find it incredibly addictive, and the few times I’ve tried something similar I find that an hour disappears into the ether without me noticing.
Why?
Well, there’s probably something about dopamine and brain reward circuitry, but there’s also something else going on, the same thing that makes zoning out in front of the TV a common activity: it doesn’t require making decisions.
‘Watch the next video’ is a simple loop that a brain can stay on for long periods of time, getting stimulation without spending resources on executive function. The same applies to any form of doomscrolling, e.g. ‘Read the next post’ on Reddit or Twitter/X.
It costs executive function to get up and go do something else, and so at each point where you could choose differently, the brain makes a micro-decision to continue the loop rather than spend finite resources choosing to do something else.
Speaking as someone who’s spent a considerable amount of time depressed, a large portion of my own depression is lack of executive function.
I can’t make decisions while depressed. I’ll be staring at a blank wall for minutes on end, unable to choose to do anything else because whatever well or pool of resources normally allows me to do so is empty.
This makes me think that executive function has a relationship to, or can be made easier by, having values and emotions that lead to genuine preferences.
If I viscerally prefer one option to another, if option A is awesome and option B disgusts me, it’s easier (costs less executive function) to choose than it would be if I didn’t have a preference. I’ve made large life decisions - car, apartment, job - quickly and easily, and yet struggled choosing a flavor of gum to buy because I genuinely don’t have a preference.
One of the most common places where I see executive function as a scarce resource is when I’m going out to dinner with others, and we need to decide where we’re going.
No one wants to make the decision. It costs executive function to suggest places, ask others for their preferences, and come up with a single outcome that satisfies everyone. Most people simply shrug and go, “Whatever works for the group,” which seems like it’s easy-going and pro-social, but actually just shunts the cognitive burden onto others.
This is commonplace: leadership requires executive function which costs cognitive resources, so people shy away from leadership the same way that a starving body shies away from wasted movement: subconsciously, as a self-preservation mechanism.
I don’t know whether or not you can increase the amount of executive function you’re capable of per day. I suspect the answer is yes, but not by much.
The better strategy is to use the limited executive function you have to build habits - that is, intervene strategically in your schedule to change your default behaviors from worse to better, slowly and over time.
How to do so is addressed here, as the first step is to notice when you want to intervene strategically, so that you can do so.
Once you understand that executive function is a scarce resource, you can start budgeting it like any other scarce resource: money, time, etc. Choose how you want to spend it, who you want to spend it on, and conserve it the rest of the time.
Instead of choosing a movie every time you want to watch one, make a list one day and just go down the list. Instead of choosing what to eat every day, make a schedule once during the week and stick to it. Instead of wasting executive function choosing to ignore your phone when you’re with your family, just turn it off or leave it in another room.
Humans aren’t machines. We have finite capacities to work, to choose, to decide, to chart a path through causal reality. We should make the most of what we’ve got.