Dr. Marc Breedlove

What about sex behavior itself?

In animals, at least, we know that there's a relationship there, that in males, in males of most species, let's take rats, if you take away the testosterone,

within a few weeks, they'll stop mounting altogether.

And if you give them testosterone, after a few weeks, they start mounting again, right?

So we know that that

Plasticity is there, and we know that it's driven by testosterone.

But in animals where they're in charge of their own testosterone, we've known for a long time that if a male is exposed to the odors of a receptive female, that causes a spike in their testosterone.

And so that's kind of preparing them for maybe I'll be lucky.

Maybe there's something coming down the pike.

And so we know that that's a reciprocal relationship.

when the animal's in charge of the hormone.

And you're getting at exactly what every textbook author has to deal with, right?

Which is, you know, as the old joke goes, you look where the light is, right?

So we know so much more about the circuits that are involved in the motor behaviors because they're relatively easy to trace and relatively easy to manipulate and relatively easy to study.

We know lots about the motor patterns in animals.

We know a lot less about the motivational patterns in animals, which in human sexual behavior is, I mean, in many ways, that's the whole show.

You know, that's really what's – and we don't really have good animal models of libido, right?

And this was brought home to me many years ago now.

I was on a session of 60 Minutes, the CBS News program.

and Leslie Stahl was there in our lab.