Happy Friday!
Everybody knows what testosterone does to a man.
It makes him aggressive, competitive, and short-tempered.
It shuts down the softer part of him and replaces it with something harder and less interested in other people.
In other words, TOXIC MASCULINITY, right?!
It's been the story my whole life, and it's the reason a lot of men still hesitate before they start treatment.
They're afraid of who they'll become.
I want to talk about a study I recently came across because it's the first piece of hard neuroscience I've seen that speaks directly to that fear (you can read it here).
For years I've argued against the meathead caricature using the only ammunition I had, which was my own experience, what my clients tell me, and what my wife noticed in me.
Today, I want to present to you some of the first evidence we have of how testosterone is shaping consciousness itself.
FYI, Taylor and I will be going live tomorrow at 10 AM EST on our YT channels and X for a coffee talk. Bring your coffee and questions! (Click here to RSVP or join).
The Study
Researchers out of Shenzhen University ran a double-blind, placebo-controlled study on 34 healthy young men, with an average age of about 21.
Each man went through the protocol twice.
In one session, he got 150 milligrams of testosterone gel on his shoulders and upper arms.
In the other session, he got an identical gel with no hormone in it.
Neither he nor the assistant applying it knew which was which.
The sessions were spaced at least a week apart, and the order was flipped between participants so it couldn't skew the results.
Every man served as his own control, which is a cleaner design than comparing one group of guys against another.
Then they waited three hours, because that's when testosterone gel peaks in the saliva.
After that came an EEG cap and 90 photographs.
In each photo, one person is circled in red. In thirty of them, that person is being welcomed into a group. In thirty, that person is being left out while everyone else laughs together. Thirty are neutral, just a guy reading a book by himself.
After each image, the men answered two questions. How good does that person in the photo feel? And how good do you feel looking at it?
The first question measures cognitive empathy, which is your ability to read what someone else is going through. The second measures emotional empathy, which is whether you actually catch some of it yourself.
The Results
So what happened?
The men's answers didn't change.
Not on cognitive empathy, not on emotional empathy, not for inclusion, not for exclusion. On testosterone, they reported feeling exactly what they reported on placebo.
If the study ended there, the headline would be that testosterone does nothing to empathy at all.
But it didn't end there. Because while their answers stayed flat, their brains did not.
Underlying Biology
At 250 milliseconds after the photo appeared, long before conscious thought has time to assemble itself, the men on testosterone showed a significantly larger brain response to watching someone get excluded.
It's an early marker of automatic emotional arousal, the brain flagging something as important before you've decided anything about it.
So testosterone made them faster and louder at detecting somebody else's social pain.
Now hold that against the second finding.
Between roughly 1.2 and 1.9 seconds, in a slower and more deliberate window, the men on testosterone showed heightened engagement with the photos of people being included.
That's the brain leaning in toward something good happening to someone else.
Think about what that means together.
If testosterone were the antisocial hormone we've been told it is, you would expect exactly one of these.
However, testosterone amplified both, at different stages of processing, in the same men, on the same afternoon.
The threat side was fast and automatic. The affiliative side was slow and considered. Testosterone touched both.
Before The Photo
And now we get to the part I can't stop thinking about.
Before any of this, before the first image loaded, the researchers recorded five minutes of resting brain activity.
Just a man sitting in a quiet room looking, with no task, no social situation, and nothing to respond to.
Testosterone had already changed what his brain was doing.
Specifically, it extended the amount of time the brain spent in a pattern the literature calls microstate E.
It's a centro-parietal configuration, and when researchers trace it back to its sources, they land on the insula, the anterior cingulate, and the medial prefrontal cortex.
Those regions form what's known as the salience network, and they're the machinery of interoception.
Interoception is a clinical word for something you already know intimately.
It's the sense of your own insides. Your heartbeat. Your gut. The tightness in your chest before you speak. The physical texture of your own emotion as it moves through your body.
Testosterone made the brain sit in that state longer at rest. And the more a given man's time in that state increased, the more his emotional empathy scores moved.
Here's the way I've come to picture it.
Emotion has always been broadcasting. Every room you walk into is thick with signal.
Think of your wife's mood before she says a word, the shift in a friend's face when you mention a certain name, or the thing your son isn't telling you.
That transmission never stopped and never needed your permission. What changes is the antenna.
Testosterone, in this study, tuned the receiver.
It raised the sensitivity of the instrument you use to pick up your own internal weather, and everything that came in afterward hit a more sensitive plate.
You feel other people more because you feel yourself more.
Final Thoughts
Three hours of elevated testosterone is not enough to completely change personality and behavior.
However, this study proves that elevating testosterone can have dramatic impact on a person’s emotional and social intelligence.
And anecdotally, what I've watched happen in men and women over months and years is the downstream version of the same thing.
People who come in flat, describing their inner life like a room with the lights off, and six months later they're telling me they cried at their daughter's recital and didn't know why.
They noticed their spouse was off before he or she said anything.
They noticed that music started landing again.
So what’s really happening?
In my opinion, it’s a person's own signal coming back online after years of running with the antenna down.
I don't think we were built to move through this world numb.
I think the depth of feeling available to a human is part of our design, not an accident of it, and I think the modern collapse in hormonal health has quietly stolen access to it from an entire generation.
Biology is super complex, and the science is always a few years behind what we know intuitively.
It usually is.
However, as I have always suspected, testosterone may very well be the one variable that enables a human to feel the full emotional depth of their own life, from the good to the bad to the ugly.
Best,
Hunter Williams
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