But the sex-script hypothesis presents a third possible explanation:
Our internal sexual responses might have been imprinted into us at an early age.
During certain critical periods in our psycho-sexual development,
particular images, stories, & sexual responses—our "sex-scripts"—
were imprinted in our brains more or less at random.
And these sexual fantasies remain in us for the rest of our lives.

     A basic analogy that might help us understand sexual imprinting
is the phenomenon of acquiring a native language.
When we were infants, we quickly and permanently acquired our first language.
It seems that our 'language-file' is open for such imprinting
only during the first few months of life.

     We do not know just when the human 'sex-file' is open for imprinting,
but we might be able to identify specific events
which have a remarkably-permanent impact on our sexual responses.
Much more research is needed to explore the possible connection between
adult sexual responses and sexually-imprinting events in childhood.