https://www.thisamericanlife.org/220/transcript

The segment where a trans man describes undergoing testosterone hormone therapy is particularly interesting, here's a quote:

The most overwhelming feeling is the incredible increase in libido and change in the way that I perceived women and the way I thought about sex.

Before testosterone, I would be riding the subway, which is the traditional hotbed of lust in the city. And I would see a woman on the subway and I would think, she's attractive. I'd like to meet her. What's that book she's reading? I could talk to her. This is what I would say. There would be a narrative. There would be this stream of language. It would be very verbal.

After testosterone, there was no narrative. There was no language whatsoever. It was just, I would see a woman who was attractive-- or not attractive. She might have an attractive quality-- nice ankles or something-- and the rest of her would be fairly unappealing to me.

But that was enough to basically just flood my mind with aggressive pornographic images, just one after another. It was like being in a pornographic movie house in my mind. And I couldn't turn it off. I could not turn it off. Everything I looked at, everything I touched turned to sex.

Note: that is not normal; he was on about twice the testosterone of a high testosterone man.

There was a recent post on here asking why so many men are so thirsty, and I think the TAL episode goes a long way towards explaining what is going on with that questions and other questions on this sub.