Five numbers appear on the screen.
Then they’re gone.
Three seconds. That’s all you get.
Then a joke shows up — something about a bear with no teeth — and by the time you’ve smiled (or groaned), the numbers feel like they belonged to someone else.
What were they?
The quiet thing that’s been slipping
Last issue I said that “better” has two dimensions for me: character and capacity. Character is the inner work — patience, integrity, how you treat people. Capacity is the equipment you bring to that work.
I’ve been thinking about one specific piece of capacity that I don’t hear people talk about enough.
Short-term memory. Working memory. The mental workspace where you hold something while life interrupts you.
It’s where you keep the beginning of a sentence while you’re listening to the end. It’s what you’re using when you walk into a room with a purpose and try to hold onto it. It’s what gets taxed when three people are talking at once and you’re trying to follow all three.
It’s also — and I say this with complete honesty — something I noticed getting softer.
Not dramatically. Just softer. The way a muscle gets when you stop using it and don’t quite notice until you try to lift something.
What I learned about why this happens
There’s a standard cognitive measure called digit span. Psychologists have used it for decades. You hear a sequence of numbers — three, then four, then five — and repeat them back. The average adult holds around seven. Some people manage nine. Some start struggling at five.
But the number isn’t really the point.
The real test is the distractor — the thing you’re asked to do in between seeing the numbers and recalling them. Because anyone can remember five digits if nothing interrupts. The interesting thing is whether you can hold them while something else claims your attention.
That’s not a game mechanic. That’s Tuesday.
And here’s what I didn’t fully understand until I started reading about this: working memory isn’t just about remembering things. It’s the foundation of how you process information in real time. Reading comprehension, following a conversation, making decisions under pressure — all of it runs on this same mental workspace.
When it weakens, everything downstream gets a little harder. And we often blame the wrong things. We call it distraction. We call it aging. We call it just being busy.
Sometimes it’s just a muscle that hasn’t been worked.
So I built a trainer
When I get frustrated with something I can’t find a good solution to, my instinct is to build the thing I wish existed.
So I did.
It’s called memTrain. It’s deliberately simple. You see a sequence of digits. The clock counts down. A joke appears — the distractor, doing its job. Then you type back what you saw.
That’s it. Two minutes. Ten rounds.
But what’s happening in those two minutes is real. You’re training the specific mechanism that fails when you walk into the kitchen and can’t remember why. The reach back through the distraction — that’s the exercise.
I built it in an afternoon, with AI as my co-builder. I described what I wanted, worked through it together, and a few hours later I was playing rounds and losing to my own creation.
That gap between what you can imagine and what you can actually build has changed. I find that worth naming.
Why capacity matters to character
Here’s the connection I keep coming back to.
We think of character as purely a matter of will. You’re patient or you’re not. You’re present or you’re not. You’re a good listener or you’re not.
But some of what looks like character is actually capacity.
When I’m mentally fatigued — when my working memory is already overloaded — I’m shorter with people. I miss things they say. I’m slower to catch the subtext. I’m not a worse person in those moments. I’m just running on less.
The muscle matters.
Go try it. One game. Two minutes.
Don’t worry about the score. Just notice what it feels like to hold something, get interrupted, and reach back for it.
memtrain.howtobebetter.ai
And as always — hit reply if this resonates. I’d like to know if you notice the same thing I did.
— Lance
p.s. — Next time: the character side of this. Specifically what happens when you use AI to examine your own blind spots. That one’s harder to write. Which probably means I should.
